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Ait Bamai Yu

Center for Environmental and Health SciencesSpecially Appointed Associate Professor

Researcher basic information

■ Degree
  • 医学博士, 北海道大学 医学研究科
■ URL
researchmap URLホームページURL■ Various IDs
Researcher number
  • 90752907
ORCID IDJ-Global ID■ Research Keywords and Fields
Research Keyword
  • Enviroment Health Scieces
  • Environmental Epidemiology
  • 環境と健康
  • Environmental chemicals
  • 有機フッ素化合物
  • Phthalates
  • Phosphate Flame Retardants
  • Child Health
  • Exposure Assessments
  • 健康リスク評価
  • Epidemiology
  • Public Health
Research Field
  • Environmental Science/Agriculture Science, Environmental load and risk assessment
  • Life Science, Hygiene and public health: excluding laboratory approach
  • Life Science, Hygiene and public health: including laboratory approach

Career

■ Career
Educational Background
  • Apr. 2011 - Dec. 2014, 北海道大学医学研究科, 公衆衛生学分野, 博士課程
  • Apr. 2009 - Mar. 2011, 北海道大学医学研究科, 公衆衛生学分野, 修士課程
  • Apr. 1998 - Mar. 2002, Hokkaido Pharmaceutical University School of Pharmacy

Research activity information

■ Awards
  • Oct. 2016, 伊藤医薬学術交流財団, 海外学会等出席研究交流助成
    アイツバマイ ゆふ
  • Sep. 2014, 北海道大学大学院医研究科, 音羽博次奨学基金助成
    アイツバマイ ゆふ
■ Papers
  • Impact of prenatal manganese and selenium exposure on childhood thyroid hormone parameters up to 4 years of age: Japan environment and children’s study
    Takeshi Yamaguchi; Hiroyoshi Iwata; Sachiko Itoh; Yu Ait Bamai; Atsuko Ikeda; Keitaro Makino; Mariko Itoh; Rahel Mesfin Ketema; Naomi Tamura; Rieko Yamamoto; Maki Tojo; Kensuke Oba; Shuntaro Morikawa; Yasuaki Saijo; Yoshiya Ito; Reiko Kishi
    Environment International, 110353, 110353, Elsevier BV, Jun. 2026
    Scientific journal
  • Latent class analysis of mobile phone usage patterns and association with sleep problems in children: Findings from the Hokkaido Birth Cohort Study
    Ammara Ajmal; Naomi Tamura; Yu Ait Bamai; Keiko Yamazaki; Toshio Yoshikawa; Rieko Yamamoto; Mariko Itoh; Keitaro Makino; Takashi Hikage; Tatsuya Kashiwa; Toshihiko Nishimura; Atsuko Ikeda; Reiko Kishi
    Computers in Human Behavior Reports, 22, 101077, 101077, Elsevier BV, May 2026
    Scientific journal
  • Associations of prenatal exposure to organophosphate pesticides with eczema and allergic rhinoconjunctivitis in 4-year-old children: The Japan Environment and Children's Study
    Megasari Marsela; Hiroyoshi Iwata; Yu Ait Bamai; Mariko Itoh; Rahel Mesfin Ketema; Takeshi Yamaguchi; Yasuaki Saijo; Yoshiya Ito; Sachiko Itoh; Keiko Yamazaki; Naomi Tamura; Keitaro Makino; Maki Tojo; Reiko Kishi; Atsuko Ikeda
    Environmental Research, 123839, 123839, Elsevier BV, Feb. 2026
    Scientific journal
  • Childhood obesity and DNA methylation in an epigenome-wide association study: findings from the Hokkaido Birth Cohort
    Hiroyoshi Iwata; Chihiro Miyashita; Takeshi Yamaguchi; Atsuko Ikeda; Ryu Miura; Machiko Minatoya; Naomi Tamura; Yu Ait Bamai; Sachiko Itoh; Keiko Yamazaki; Rahel Mesfin Ketema; Mariko Itoh; Maki Tojo; Rieko Yamamoto; Keitaro Makino; Reiko Kishi
    Clinical Epigenetics, Springer Science and Business Media LLC, 01 Dec. 2025
    Scientific journal
  • Toxic metals and trace elements in maternal blood and urinary tract infection during the first 2 years of life: The Japan Environment and Children's Study
    Keitaro Makino; Hiroyoshi Iwata; Takeshi Yamaguchi; Atsuko Ikeda; Yu Ait Bamai; Sachiko Itoh; Mariko Itoh; Maki Tojo; Naomi Tamura; Rieko Yamamoto; Rahel Mesfin Ketema; Yasuaki Saijo; Yoshiya Ito; Reiko Kishi
    Science of The Total Environment, 1006, 180895, 180895, Elsevier BV, Dec. 2025
    Scientific journal
  • The impact of pediatric constipation on appendicitis: a prospective birth cohort in the Japan Environment and Children's Study.
    Hiroyoshi Iwata; Takeshi Yamaguchi; Sachiko Itoh; Yu Ait Bamai; Atsuko Ikeda; Keitaro Makino; Mariko Itoh; Maki Tojo; Rieko Yamamoto; Naomi Tamura; Rahel Mesfin Ketema; Yasuaki Saijo; Yoshiya Ito; Reiko Kishi
    BMC pediatrics, 25, 1, 962, 962, 26 Nov. 2025, [International Magazine]
    English, Scientific journal, BACKGROUND: This study aimed to examine the association between constipation and appendicitis in children using data from a nationwide birth cohort, the Japan Environment and Children's Study (JECS). METHODS: Data were obtained from 64,772 children and their mothers participating in JECS, which included over 100,000 pregnancies across 15 regional centres in Japan. Pediatric constipation was assessed at age three using the Rome III criteria, while appendicitis cases were identified between ages three to four. Logistic regression analyses, including univariable and multivariable models, were conducted to evaluate associations. Additional analyses were stratified by sex. RESULTS: Among the 64,772 children analyzed, 156 cases of appendicitis were identified between the ages of 3 and 4 years. Logistic regression suggested a possible association between constipation and an increased risk of appendicitis (univariable odds ratio [OR]: 1.38, 95% confidence interval [CI]: 0.87–2.10; multivariable OR: 1.36, 95% CI: 0.86–2.06). Although the associations did not reach statistical significance, the point estimates consistently indicated a trend toward increased risk. CONCLUSION: Although our analyses of children aged 3–4 years did not yield statistically significant associations, the observed trends may suggest a potential link between constipation and appendicitis. These findings should be interpreted only as exploratory, and further studies in different age groups, including older children and adults, are warranted to confirm or refute this possible association. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12887-025-06263-7.
  • Whole-Body SAR Evaluation under Far-Field Exposure with Daily Posture Variability: Toward an Epidemiologically Relevant Assessment
    Koki Kusakabe; Takashi Hikage; Toshihiko Nishimura; Tatsuya Kashiwa; Naomi Tamura; Yu Ait Bamai; Atsuko Ikeda; Reiko Kishi
    2025 International Symposium on Antennas and Propagation (ISAP), 1, 2, IEEE, 27 Oct. 2025
    International conference proceedings
  • Prediction of Kawasaki disease coronary artery lesions in the Japan Environment and Children’s Study
    Hiroyoshi Iwata; Takeshi Yamaguchi; Naomi Tamura; Yu Ait Bamai; Atsuko Ikeda; Mariko Itoh; Rieko Yamamoto; Maki Tojo; Rahel Mesfin Ketema; Keiko Yamazaki; Sachiko Itoh; Keitaro Makino; Satoru Shida; Yasuaki Saijo; Yoshiya Ito; Reiko Kishi
    Annals of Pediatric Cardiology, 18, 5, 437, 446, Ovid Technologies (Wolters Kluwer Health), Sep. 2025
    Scientific journal, Objective:

    This study aimed to validate a composite of previously identified risk factors for predicting coronary artery lesions in Japanese children with Kawasaki Disease (KD).

    Materials and Methods:

    Children diagnosed with KD from the Japan Environment and Children’s Study (JECS) cohort were included. We assessed the discriminative ability of the model using the area under the curve (AUC) and evaluated its calibration using calibration plots. Based on clinical insights, we derived our original model, which consisted of variables established in previous score models or studies. Using the bootstrap method, internal validation was assessed with the AUC and calibration slope.

    Results:

    Our analysis included 959 children with KD, derived from 104,062 pediatric records contained in the JECS. Our model comprised the following variables: sex, hematocrit, platelet count, C-reactive protein, and serum sodium levels. The mean and 95% confidence intervals of the AUCs for the Harada, Egami, and Kobayashi models were 0.66 (0.59–0.72), 0.59 (0.52–0.66), and 0.64 (0.56–0.72), respectively. Our score model with bootstrap analyses produced an AUC of 0.80 (0.68–0.91) and a calibration slope of 1.01.

    Conclusions:

    We built and evaluated our score model using indicators that were easily accessible with a moderate-to-high AUC and stable calibration results, indicating the high reliability of the model for clinical application. Further studies are required to validate our model in other cohorts.
  • Guidance on minimum information requirements (MIR) from designing to reporting human biomonitoring (HBM).
    Maryam Zare Jeddi; Karen S Galea; Jillian Ashley-Martin; Julianne Nassif; Tyler Pollock; Devika Poddalgoda; Konstantinos M Kasiotis; Kyriaki Machera; Holger M Koch; Marta Esteban López; Ming Kei Chung; Jihyon Kil; Kate Jones; Adrian Covaci; Yu Ait Bamai; Mariana F Fernandez; Robert Pasanen Kase; Henriqueta Louro; Maria J Silva; Tiina Santonen; Andromachi Katsonouri; Argelia Castaño; Lesliam Quirós-Alcalá; Elizabeth Ziying Lin; Krystal Pollitt; Ana Virgolino; Paul T J Scheepers; Lisa Jo Melnyk; Vicente Mustieles; Ana Isabel Cañas Portilla; Susana Viegas; Natalie von Goetz; Ovnair Sepai; Emily Bird; Thomas Göen; Silvia Fustinoni; Manosij Ghosh; Hubert Dirven; Jung-Hwan Kwon; Courtney Carignan; Yuki Mizuno; Yuki Ito; Yankai Xia; Shoji F Nakayama; Konstantinos C Makris; Patrick J Parsons; Melissa Gonzales; Michael Bader; Maria Dusinska; Aziza Menouni; Radu Corneliu Duca; Kaoutar Chbihi; Samir El Jaafari; Lode Godderis; An van Nieuwenhuyse; Asif Qureshi; Imran Ali; Carla Costa Trindade; Joao Paulo Teixeira; Alena Bartonova; Giovanna Tranfo; Karine Audouze; Steven Verpaele; Judy LaKind; Hans Mol; Jos Bessems; Barbara Magagna; Maisarah Nasution Waras; Alison Connolly; Marc Nascarella; Wonho Yang; Po-Chin Huang; Jueun Lee; Henri Heussen; Ozlem Goksel; Masud Yunesian; Leo W Y Yeung; Gustavo Souza; Ana Maria Vekic; Erin N Haynes; Nancy B Hopf
    Environment international, 202, 109601, 109601, Aug. 2025, [International Magazine]
    English, Scientific journal, Human biomonitoring (HBM) provides an integrated chemical exposures assessment considering all routes and sources of exposure. The accurate interpretation and comparability of biomarkers of exposure and effect depend on harmonized, quality-assured sampling, processing, and analysis. Currently, the lack of broadly accepted guidance on minimum information required for collecting and reporting HBM data, hinders comparability between studies. Furthermore, it prevents HBM from reaching its full potential as a reliable approach for assessing and managing the risks of human exposure to chemicals. The European Chapter of the International Society of Exposure Science HBM Working Group (ISES Europe HBM working group) has established a global human biomonitoring community network (HBM Global Network) to develop a guidance to define the minimum information to be collected and reported in HBM, called the "Minimum Information Requirements for Human Biomonitoring (MIR-HBM)". This work builds on previous efforts to harmonize HBM worldwide. The MIR-HBM guidance covers all phases of HBM from the design phase to the effective communication of results. By carefully defining MIR for all phases, researchers and health professionals can make their HBM studies and programs are robust, reproducible, and meaningful. Acceptance and implementation of MIR-HBM Guidelines in both the general population and occupational fields would improve the interpretability and regulatory utility of HBM data. While implementation challenges remain-such as varying local capacities, and ethical and legal differences at the national levels, this initiative represents an important step toward harmonizing HBM practice and supports an ongoing dialogue among policymakers, legal experts, and scientists to effectively address these challenges. Leveraging the data and insights from HBM, policymakers can develop more effective strategies to protect public health and ensure safer working environments.
  • Development of a Liquid Chromatography-Tandem Mass Spectrometry Method for Oxylipin Analysis and Its Application to Children's Plasma.
    Yonghan Li; Siddabasave Gowda B Gowda; Divyavani Gowda; Atsuko Ikeda; Yu Ait Bamai; Rahel Mesfin Ketema; Reiko Kishi; Hitoshi Chiba; Shu-Ping Hui
    Diagnostics (Basel, Switzerland), 15, 15, 25 Jul. 2025, [International Magazine]
    English, Scientific journal, Background/Objectives: Oxylipins, a family of oxygenated natural products derived from polyunsaturated fatty acids (PUFAs), play crucial roles in various physiological processes. Evaluating their levels in vivo helps to reveal their roles in health and disease. Because of the numerous isomers of oxylipins, it is essential to develop efficient and precise analytical methods for their identification and quantification. The objective of this study is to establish a quantitative method for oxylipin analysis and its application to the assessment of oxylipins in children's plasma, with potential implications for diagnostic use in pediatric populations. Methods: A liquid chromatography-electrospray ionization-tandem mass spectrometry method was developed to quantify 64 oxylipins and four precursor PUFAs within 36 min. The limits of quantification ranged from 0.25 to 50 pg, with most analytes showing recoveries and matrix effects between 85 and 110% and between 90 and 110%, respectively. Intra- and inter-day precision values were within 15%. The established method was applied to plasma samples from children aged 9-12 years (boys = 181; girls = 161) in Hokkaido, Japan, to assess the relation between plasma oxylipin and PUFA levels and age, sex, and body mass index. Results: There was no significant correlation between oxylipin levels and age, sex, or body mass index. However, among the PUFAs, boys had higher eicosapentaenoic acid and arachidonic acid levels than those of girls, with a significant increase in eicosapentaenoic acid levels in the overweight group compared with those in the underweight group. Conclusions: We successfully developed a simple and highly selective method for the analysis of oxylipins in preadolescent children's plasma samples. Thus, this study provides a foundation for broader application of the developed method to different biological samples in future studies.
  • Associations between urinary phthalate metabolites and reproductive, adrenal, and gonadotropic hormones in peripubertal children: the Hokkaido study.
    Ayaka Yasuda; Yu Ait Bamai; Takeshi Yamaguchi; Rahel Mesfin Ketema; Yi Zeng; Megasari Marsela; Yoshinori Ikenaka; Akie Nakamura; Takeya Kitta; Masafumi Kon; Atsushi Manabe; Reiko Kishi; Hiroyuki Kojima; Atsuko Ikeda
    Environmental research, 276, 121535, 121535, 03 Apr. 2025, [International Magazine]
    English, Scientific journal, Phthalates have raised concerns regarding the disruption of hormone synthesis and signaling. The purpose of this study was to investigate the associations between urinary phthalate metabolites and 18 hormones, including reproductive, adrenal, and gonadotropic hormones, in peripubertal children. The study comprised a cross-sectional analysis of participants in the Hokkaido Birth Cohort Study. We collected data from 429 school children aged 9-12 living in Sapporo, Japan. Ten phthalate metabolites and 14 steroid hormones were analyzed using LC-MS/MS, whereas four peptide hormones were detected using immunoassays. Multivariable linear regression, quantile-based g-computation (qg-computation), and Bayesian kernel machine regression (BKMR) were used to investigate the associations between the individual phthalate metabolites and the phthalate mixtures with hormone levels, as well as with puberty based on hormone levels. In girls, we found that higher phthalate metabolite levels, as well as phthalate mixtures, were significantly associated with lower dehydroepiandrostenedione-sulfate (DHEA-S) and higher (androstenedione + testosterone) / DHEA-S. The higher phthalate mixture showed lower levels of LH, FSH, and cortisol levels among girls, whereas higher 11-deoxycortisol levels. In boys, a higher phthalates mixture was significantly associated with a higher estradiol/testosterone ratio, whereas lower levels of insulin-like factor-3 (INSL3), testosterone, (androstenedione + testosterone)/DHEA-S, testosterone/androstenedione, and cortisol/cortisone. Higher phthalate mixtures were associated with lower prevalence of puberty in girls. These findings indicate that phthalate exposure may disrupt the hormones in children during puberty.
  • Impact of prenatal exposure to per- and polyfluoroalkyl substances on developmental delays in 4-year-old children: The Japan Environment and Children’s study
    Mariko Itoh; Sumitaka Kobayashi; Hiroyoshi Iwata; Yu Ait Bamai; Rahel Mesfin Ketema; Takeshi Yamaguchi; Keiko Yamazaki; Naomi Tamura; Maki Tojo; Satoshi Suyama; Sachiko Itoh; Chihiro Miyashita; Yasuaki Saijo; Yoshiya Ito; Shoji F. Nakayama; Michihiro Kamijima; Reiko Kishi
    Environment International, 198, 109434, 109434, Elsevier BV, Apr. 2025, [International Magazine]
    English, Scientific journal, Although per- and polyfluoroalkyl substances (PFAS) have raised global concern due to their adverse effects on children's development, the association between prenatal exposure to PFAS and the achievement of developmental milestones in preschool children remains unclear. This study aimed to examine the individual and cumulative associations between prenatal PFAS and developmental delay in 4-year-old children. We used data from 15,131 mothers (15,175 children) in the Japan Environment and Children Study (JECS), an ongoing nationwide prospective birth cohort. Among 28 PFAS measured in maternal plasma, eight with detection frequencies ≥ 60 % were analyzed. Developmental delays were assessed using the Japanese version of the Ages and Stages Questionnaires third edition (JASQ-3), a self-administered screening tool, with suspicion of developmental delay indicated by total scores falling below the Japanese version cutoffs for the five JASQ-3 domains (communication, gross motor, fine motor, problem solving, and personal-social). Univariate and multivariable logistic regression analysis and quantile g-computation were applied. Findings revealed that these eight PFAS were not significantly associated with higher odds of developmental delay across any JASQ-3 domain, nor did their combined effects. However, the effects of PFAS substances not measured in this study and the impact of continued postnatal exposure to PFAS on developmental delays remain a concern. Continuous investigation of the effects of PFAS on development throughout the lifespan is necessary.
  • Mediation of prenatal cotinine and 8-hydroxy-2’-deoxyguanosine levels on infant birth size in the Japan Environment and Children’s Study (JECS)
    Sumitaka Kobayashi; Hiroyoshi Iwata; Takeshi Yamaguchi; Naomi Tamura; Mariko Itoh; Maki Tojo; Keiko Yamazaki; Sachiko Itoh; Chihiro Miyashita; Yu Ait Bamai; Yukihiro Sato; Yasuaki Saijo; Yoshiya Ito; Reiko Kishi
    Reproductive Toxicology, 135, 108905, 108905, Elsevier BV, Apr. 2025, [International Magazine]
    English, Scientific journal, Prenatal passive and active smoking and oxidative stress are of concern because of their adverse effects on infant birth sizes. This study aimed to examine the mediation of maternal cotinine and 8-hydroxy-2'-deoxyguanosine (8-OHdG) levels during pregnancy on infant birth size by occupation. The study used data from 72,544 participants of the Japan Environment and Children's Study (JECS), an ongoing nationwide prospective birth cohort. We used maternal cotinine in urine as a biomarker for prenatal passive and active smoking and maternal 8-OHdG as a biomarker for prenatal oxidative stress. In all participants, multiple linear regression analysis adjusted for covariates showed birth weight (95 % confidence interval; CI) at cotinine level 5 (active smoker level) decreased by 140 (127, 152) g compared to birth weight at cotinine level 1 (non-smoker level), and birth weight at the fourth quartile of 8-OHdG level decreased by 18 (12, 25) g compared to birth weight at the first quartile of 8-OHdG level. When stratified by maternal occupation, no association was found between the cotinine levels of maternal passive smoking exposure and birth size. The association between cotinine levels and decreased birth size in all the participants was mediated by 8-OHdG. The results showed that there was a maternal cotinine levels during pregnancy on birth size in infants.
  • Phosphate Flame Retardants and Plasticizers and Their Association with Reproductive and Steroid Hormone Levels among Peripubertal-Aged Children: The Hokkaido Birth Cohort Study.
    Atsuko Ikeda; Takeshi Yamaguchi; Yu Ait Bamai; Maarten Roggeman; Yoshinori Ikenaka; Yi Zeng; Ayaka Yasuda; Rahel Mesfin Ketema; Megasari Marsela; Celine Gys; Fatima den Ouden; Sachiko Itoh; Akie Nakamura; Takeya Kitta; Masafumi Kon; Atsushi Manabe; Adrian Covaci; Reiko Kishi
    Environmental science & technology, 59, 10, 4820, 4831, 18 Mar. 2025, [International Magazine]
    English, Scientific journal, This cross-sectional study investigated associations between exposure to organophosphate flame retardants and plasticizers (PFRs) and reproductive and steroid hormones in peripubertal children from the Hokkaido Birth Cohort (429 children aged 9-12 years; between September 2017 and March 2020). Thirteen urinary PFR metabolites and 14 plasma steroid hormones were investigated using LC-MS/MS and four reproductive hormones were investigated using immunoassays. Linear regression for single PFR, quantile g-computation, and Bayesian machine kernel regression (BKMR) models for the PFR mixtures were used to examine the association between hormones and PFRs. Among boys, significant positive associations were observed between estradiol and ΣTCIPP and ΣTBOEP, and inverse associations were identified between insulin-like factor-3 (INSL3) and ΣTCIPP, and between luteinizing hormone (LH) and ΣEHDPHP. The PFR mixture was associated with the trends of increasing estradiol and androstenedione, and decreasing cortisol, cortisone, LH, inhibin B, and INSL3. Among girls, androstenedione and ΣTCIPP, testosterone and ΣEHDPHP, (androstenedione + testosterone)/DHEA-S and ΣTCIPP, and ΣEHDPHP and ΣTPHP were significantly correlated. The PFR mixture showed trends of increasing testosterone, androstenedione, and inhibin B, and decreasing cortisol, cortisone, and INSL3. Individual PFRs and PFR mixtures altered steroids and reproductive hormones in peripubertal children.
  • Application of Liquid Chromatography/Tandem Mass Spectrometry for Quantitative Analysis of Plasmalogens in Preadolescent Children—The Hokkaido Study
    Chen, Y.; Gowda, S.G.B.; Gowda, D.; Jayaprakash, J.; Nath, L.R.; Ikeda, A.; Bamai, Y.A.; Ketema, R.M.; Kishi, R.; Chiba, H.; Hui, S.-P.
    Diagnostics, 15, 6, 16 Mar. 2025, [Peer-reviewed], [International Magazine]
    English, Scientific journal, Background: Plasmalogens (Pls) are phospholipids with a unique structure, abundant in the brain and heart. Due to their chemical instability and analytical difficulties, less information is available compared to other phospholipids. The importance of Pls in several cellular processes is known, one of which is their protective effect against oxidative damage. The physiological role of Pls in human development has not been elucidated. Despite their clinical importance, the quantitative analysis of Pls in children's plasma has been limited. Methods: This study aims to determine the plasma levels of Pls in prepubertal children using liquid chromatography/tandem mass spectrometry (LC-MS/MS). The plasma samples used were obtained from 9- to 12-year-old girls (n = 156) and boys (n = 178), n = 334 in total, who participated in the Hokkaido study. Results: Ethanolamine plasmalogen (PlsEtn) and choline plasmalogen (PlsCho), both carrying eicosapentaenoic acid, were significantly lower in girls than in boys. In both sexes, the plasmalogen levels for the 12-year-old children were lower than those for the 9-year-old children. PlsCho (16:0/18:2) was lower in the overweight children than in the normal-weight children for both sexes. PlsEtn (18:0/20:4) was the most abundant ethanolamine-type plasmalogen in both sexes. Conclusions: This study is the first report on plasmalogen levels and molecular types in children's plasma. This study provides the information needed to understand the role of Pls in human developmental processes and may open up new opportunities in the future to control age-related changes in Pls.
  • 胎児期フタル酸エステル類混合曝露と前思春期の性ホルモンとの関連 北海道スタディ
    安田 彩夏; アイツバマイ ゆふ; 山口 健史; ケテマ・ラヒルメスフィン; 曾 怡; 池中 良徳; メガサリ・マルセラ; 岸 玲子; 小島 弘幸; 池田 敦子
    日本衛生学雑誌, 80, Suppl., S233, S233, (一社)日本衛生学会, Mar. 2025
    Japanese
  • Association between prenatal exposure to maternal metal and trace elements and Streptococcus infection: A prospective birth cohort in the Japan Environment and Children’s Study
    Hiroyoshi Iwata; Atsuko Ikeda; Mariko Itoh; Rahel Mesfin Ketema; Naomi Tamura; Takeshi Yamaguchi; Keiko Yamazaki; Rieko Yamamoto; Maki Tojo; Yu Ait Bamai; Yasuaki Saijo; Yoshiya Ito; Reiko Kishi
    PLOS ONE, 20, 2, e0319356, e0319356, Public Library of Science (PLoS), 27 Feb. 2025, [International Magazine]
    English, Scientific journal, Background

    Streptococcus infection is a common and potentially severe bacterial infection which remains a global public health challenge, underscoring the necessity of investigating potential risk factors.

    Aims

    The present study aims to assess the association between metal and trace element exposure and Streptococcus infection using a prospective nationwide birth cohort, the Japan Environment and Children’s Study (JECS).

    Methods

    The JECS obtained data from over 100,000 pregnancies through 15 Regional Centres across Japan. We assessed toxic metal and trace element levels among pregnant mothers and Streptococcus infection among their children, born between 2011 and 2014, at age three to four. Analysis was performed using univariable and multivariable logistic regressions, as well as Quantile g-computation. We also conducted quartile regressions to assess the effects of higher serum selenium levels and potential interactions between selenium and mercury.

    Results

    Among 74,434 infants and their mothers, univariable and multivariable regression analyses found that selenium and mercury each had an inverse association with Streptococcus infection incidence. Quantile g-computation analysis yielded results consistent with the primary regression analyses. Quartile regression suggested that serum selenium levels above the third quartile were inversely associated with later Streptococcus infection incidence, but no interaction between selenium and mercury was found.

    Conclusions

    These findings imply that maternal selenium exposure may have protective effects on Streptococcus infection among children. Further studies should explore the role of pediatric selenium in immune responses to infectious diseases, especially Streptococcus infection.
  • One year respiratory and neurodevelopmental outcome of premature neonates after exposure to plasticizers in the neonatal intensive care unit – A prospective cohort study
    Panneel, L.; Cleys, P.; Ait Bamai, Y.; Dewispelaere, L.; Laroche, S.; Van Hoorenbeeck, K.; Verhulst, S.; Covaci, A.; Mulder, A.; Jorens, P.G.
    Environmental Research, 274, 121266, 121266, 2025, [International Magazine]
    English, Scientific journal
  • Association of Phthalate Exposure with Respiratory and Allergic Symptoms and Type 2 and Non-Type 2 Inflammation: The Hokkaido Study
    Ketema, R.M.; Ait Bamai, Y.; Goudarzi, H.; Yamaguchi, T.; Zeng, Y.; Yasuda, A.; Marsela, M.; Konno, S.; Kishi, R.; Ikeda, A.
    Environmental Science and Technology, 59, 15, 7541, 7549, 2025, [International Magazine]
    English, Scientific journal, Phthalate exposure is linked to asthma and allergic symptoms, yet their individual and combined effects on symptoms and inflammatory biomarkers, type 2 (T2) and non-T2, remain unexplored. This study examined the association of phthalate metabolites with allergic symptoms (wheeze, allergic rhinoconjunctivitis, and eczema), T2 biomarker (fraction of exhaled nitric oxide (FeNO), blood eosinophil count, and total immunoglobulin E (IgE)), and non-T2 biomarker (absolute neutrophil count (ANC)) and also their association with oxidative stress biomarkers, such as 4-hydroxynonenal, hexanoyl-lysine, and 8-hydroxy-2-deoxyguanosine. Ten urinary phthalate metabolites were measured using UPLC-MS/MS in 421 children (aged 9-12 years) from The Hokkaido Cohort, Japan. Symptoms were defined using the International Study of Asthma and Allergies in Childhood questionnaire, and biomarkers were measured in blood. Logistic regression assessed individual metabolites, while quantile-g computation and Bayesian kernel machine regression analyzed mixture effects on binary outcomes. Individual analysis showed that MnBP (mono-n-butyl phthalate) was positively associated with allergic rhinoconjunctivitis and eosinophil ≥ 300 cells/μL, while ∑DBP (dibutyl phthalate) and OH-MiNP (mono-hydroxy-isononyl phthalate) were linked with FeNO ≥ 35 ppb. DEHP (di(2-ethylhexyl) phthalate) metabolites were associated with a high prevalence of blood eosinophils ≥ 300 cells/μL. We found a positive association between phthalates and oxidative stress markers, but no link was observed between oxidative stress and inflammatory markers. Mixture analysis identified MnBP as a major contributor to the high FeNO level, with di-n-butyl phthalate (DnBP) and DEHP metabolites contributing to eosinophil count ≥ 300 cells/μL and ANC ≥ 4400 cells/μL. These findings suggest that phthalate exposure from DnBP and DEHP is associated with immune dysregulation by triggering both T2 and non-T2 inflammatory responses.
  • Plasma Lipidomics of Preadolescent Children: A Hokkaido Study
    Jayashankar Jayaprakash; Siddabasave Gowda B. Gowda; Divyavani Gowda; Atsuko Ikeda; Yu Ait Bamai; Rahel Mesfin Ketema; Reiko Kishi; Yifan Chen; Hitoshi Chiba; Shu-Ping Hui
    Journal of Lipids, 2025, 3106145, 3106145, Jan. 2025, [International Magazine]
    English, Scientific journal, Lipids are the most abundant biomolecules of human plasma, and their balance plays a significant role in health and disease management. Despite the importance of lipids, the studies focused on the comprehensive determination of the plasma lipidome in children are limited. In this study, we investigated the sex, age, and weight-specific changes in the plasma lipidome of nonfasting preadolescent children aged 9-12 years (n = 342) using a nontargeted liquid chromatography-mass spectrometry technique. A total of 219 lipid species were characterized in the plasma samples. Multivariate analysis revealed that boys and girls have similar lipid profiles, but relatively higher levels of capric acid-composed triacylglycerols (TGs) were observed in plasma samples of boys. Saturated fatty acids are the most abundant fatty acyls followed by mono- and polyunsaturated fatty acids in the plasma of both boys and girls. Sphingolipids such as ceramides, hexosylceramides, sphingomyelin, and a phospholipid (phosphatidylinositol) were relatively higher in the plasma of a 10-year-old group than other age groups. Plasma levels of TG and phosphatidylserine were increased within age from 9 to 12 years. Furthermore, most of the TG molecular species were increased in the plasma of overweight children compared to the normal range groups. The receiver operating characteristic analysis results show that TG (10:0/10:0/18:1) could be a specific marker for childhood obesity (area under the curve (AUC) = 0.72). Overall, this study highlights the altered plasma lipidome in preadolescent children for sex, age, and percentage of overweight. Early detection of lipid markers for obesity would be a promising target for developing therapeutic strategies.
  • Association between prenatal tobacco exposure and attention-deficit/hyperactivity disorder related characteristics at 6 and 8 years: a birth cohort in Japan
    Mariko Itoh; Sumitaka Kobayashi; Shinkichi Nishihara; Chihiro Miyashita; Keiko Yamazaki; Naomi Tamura; Satoshi Suyama; Atsuko Ikeda; Sachiko Itoh; Yu Ait Bamai; Takeshi Yamaguchi; Hideyuki Masuda; Sharon Hanley; Reiko Kishi
    BMJ Open, 14, 12, e087406, e087406, BMJ, 26 Dec. 2024, [International Magazine]
    English, Scientific journal, Objectives

    To examine the association between maternal plasma cotinine concentrations during pregnancy and attention-deficit/hyperactivity disorder (ADHD) related characteristics in children.

    Design

    Prospective birth cohort study from the Hokkaido Study on Environment and Children’s Health.

    Setting

    Hokkaido, Japan.

    Participants

    A total of 7217 children were included in the analysis. Their mothers were recruited to this study between 2003 and 2012 during early pregnancy. Blood samples of mothers in their third trimester of pregnancy were obtained.

    Main outcome measures

    ADHD-related characteristics screened by the ADHD-Rating Scale (ADHD-RS) in children at 6 and 8 years of age.

    Results

    The mothers were classified into three groups according to plasma cotinine levels (median=0.22 ng/mL)—non-smokers (≤0.21 ng/mL), passive smokers (0.22–11.48 ng/mL) and active smokers (≥11.49 ng/mL). ADHD was suspected in 302 (8.6%), 334 (10.9%) and 90 (14.5%) children in the non-smoker, passive smoker and active smoker groups, respectively. Children born to mothers in the smoking group had a statistically significant increased risk of ADHD-related characteristics (adjusted RR=1.49, 95% CI=1.19–1.86 and adjusted RR=1.20, 95% CI=1.03–1.40 for the active and passive smoking groups, respectively).

    Conclusion

    This large Japanese cohort study suggests an association between smoking during pregnancy and the risk of ADHD in children 6 and 8 years of age.
  • Impact of wheat sensitization on wheeze and T2 phenotypes in general population of children
    Houman Goudarzi; Atsuko Ikeda; Yu Ait Bamai; Isao Yokota; Chihiro Miyashita; Wilfried Karmaus; Reiko Kishi; Satoshi Konno
    Journal of Allergy and Clinical Immunology: Global, 3, 4, 100300, 100300, Nov. 2024, [International Magazine]
    English, Scientific journal
  • Occurrence of short- and ultra-short chain PFAS in drinking water from Flanders (Belgium) and implications for human exposure
    Francesca Cappelli; Yu Ait Bamai; Kobe Van Hoey; Da Hye Kim; Adrian Covaci
    Environmental Research, 260, 119753, 119753, 01 Nov. 2024, [International Magazine]
    English, Scientific journal
  • 前思春期の学童における血中性・ステロイドホルモン濃度 北海道スタディ
    安田 彩夏; 山口 健史; 池中 良徳; アイツバマイ ゆふ; 岸 玲子; 小島 弘幸; 池田 敦子
    日本成長学会雑誌, 30, 2, 86, 86, 日本成長学会, Sep. 2024
    Japanese
  • Determination of plasma lysophosphatidylethanolamines (lyso-PE) by LC-MS/MS revealed a possible relation between obesity and lyso-PE in Japanese preadolescent children: the Hokkaido study.
    Nao Inoue; Siddabasave Gowda B Gowda; Divyavani Gowda; Toshihiro Sakurai; Atsuko Ikeda-Araki; Yu Ait Bamai; Rahel Mesfin Ketema; Reiko Kishi; Hitoshi Chiba; Shu-Ping Hui
    Annals of clinical biochemistry, 62, 1, 45632241280352, 45632241280352, 21 Aug. 2024, [International Magazine]
    English, Scientific journal
  • Quantitative determination of plasma cholesteryl ester levels in Japanese preadolescents from the Hokkaido study using liquid chromatography/tandem mass spectrometry.
    Divyavani Gowda; Siddabasave Gowda B Gowda; Atsuko Ikeda; Rahel Mesfin Ketema; Yu Ait Bamai; Reiko Kishi; Hitoshi Chiba; Shu-Ping Hui
    Steroids, 211, 109498, 109498, 13 Aug. 2024, [International Magazine]
    English, Scientific journal
  • Link between Wi-Fi, cordless devices, mobile phone usage patterns, and behavioral problems among Japanese children: A prospective cohort study.
    Ammara Ajmal; Keiko Yamazaki; Naomi Tamura; Yu Ait Bamai; Toshio Yoshikawa; Takashi Hikage; Atsuko Ikeda; Reiko Kishi
    Environmental research, 261, 119715, 119715, 02 Aug. 2024, [International Magazine]
    English, Scientific journal
  • Alterations in plasma short-chain fatty acids in preadolescence children: The Hokkaido study
    Yonghan Li; Siddabasave Gowda B. Gowda; Divyavani Gowda; Atsuko Ikeda; Yu Ait Bamai; Rahel Mesfin Ketema; Reiko Kishi; Hitoshi Chiba; Shu-Ping Hui
    Journal of Chromatography B, 1242, 124191, 124191, Elsevier BV, Jul. 2024, [International Magazine]
    English, Scientific journal
  • HBM4EU E-waste study: Assessing persistent organic pollutants in blood, silicone wristbands, and settled dust among E-waste recycling workers in Europe
    Adam Cseresznye; Emilie M. Hardy; Yu Ait Bamai; Paulien Cleys; Giulia Poma; Govindan Malarvannan; Paul T.J. Scheepers; Susana Viegas; Carla Martins; Simo P. Porras; Tiina Santonen; Lode Godderis; Jelle Verdonck; Katrien Poels; Maria João Silva; Henriqueta Louro; Inese Martinsone; Lāsma Akūlova; Maurice van Dael; An van Nieuwenhuyse; Selma Mahiout; Radu Corneliu Duca; Adrian Covaci
    Environmental Research, 250, 118537, 118537, 01 Jun. 2024, [International Magazine]
    English, Scientific journal
  • Prenatal risk factors of indoor environment and incidence of childhood eczema in the Japan environment and children's study.
    Yu Ait Bamai; Chihiro Miyashita; Atsuko Ikeda-Araki; Keiko Yamazaki; Sumitaka Kobayashi; Sachiko Itoh; Yasuaki Saijo; Yoshiya Ito; Eiji Yoshioka; Yukihiro Sato; Reiko Kishi; Michihiro Kamijima; Shin Yamazaki; Yukihiro Ohya; Nobuo Yaegashi; Koichi Hashimoto; Chisato Mori; Shuichi Ito; Zentaro Yamagata; Hidekuni Inadera; Takeo Nakayama; Tomotaka Sobue; Masayuki Shima; Hiroshige Nakamura; Narufumi Suganuma; Koichi Kusuhara; Takahiko Katoh
    Environmental research, 252, Pt 2, 118871, 118871, 03 Apr. 2024, [International Magazine]
    English, Scientific journal
  • Ongoing exposure to endocrine disrupting phthalates and alternative plasticizers in neonatal intensive care unit patients
    Lucas Panneel; Paulien Cleys; Giulia Poma; Yu Ait Bamai; Philippe G. Jorens; Adrian Covaci; Antonius Mulder
    Environment International, 186, 108605, 108605, Apr. 2024, [International Magazine]
    English, Scientific journal
  • Identification, semi-quantification and risk assessment of contaminants of emerging concern in Flemish indoor dust through high-resolution mass spectrometry
    Lidia Belova; Maarten Roggeman; Fatima den Ouden; Paulien Cleys; Yu Ait Bamai; Shanshan Yin; Lu Zhao; Jasper Bombeke; Jan Peters; Patrick Berghmans; Celine Gys; Alexander L.N. van Nuijs; Giulia Poma; Adrian Covaci
    Environmental Pollution, 345, 123475, 123475, 15 Mar. 2024, [International Magazine]
    English, Scientific journal
  • 前思春期のフタル酸エステル類曝露とステロイドホルモン値との関連 北海道スタディ
    安田 彩夏; アイツバマイ ゆふ; 山口 健史; ケテマ・ラヒルメスフィン; 曾 怡; 池中 良徳; 宮下 ちひろ; マルセラ・メガサリ; 岸 玲子; 小島 弘幸; 池田 敦子
    日本衛生学雑誌, 79, Suppl., S209, S209, (一社)日本衛生学会, Mar. 2024
    Japanese
  • 口唇口蓋裂を有する1歳児の下気道感染症罹患リスク エコチル調査より
    佐藤 遊洋; 吉岡 英治; 西條 泰明; 宮本 敏伸; 東 寛; 棚橋 祐典; 伊藤 善也; 小林 澄貴; 湊屋 街子; アイツバマイ ゆふ; 山崎 圭子; 伊藤 佐智子; 宮下 ちひろ; 池田 敦子; 岸 玲子
    日本衛生学雑誌, 79, Suppl., S239, S239, (一社)日本衛生学会, Mar. 2024
    Japanese
  • Stable isotope ratios and current-use pesticide levels in edible insects: Implications on chemical food safety
    Alicia Macan Schönleben; Shanshan Yin; Ethan Strak; Alison Johnson; Lidia Belova; Yu Ait Bamai; Alexander L.N. van Nuijs; Giulia Poma; Adrian Covaci
    Food Research International, 179, 114020, 114020, Mar. 2024, [International Magazine]
    English, Scientific journal
  • Organophosphate flame retardants associated with increased oxidative stress biomarkers and elevated FeNO levels in general population of children: The Hokkaido study
    Zeng, Y.; Ait Bamai, Y.; Goudarzi, H.; Ketema, R.M.; Roggeman, M.; den Ouden, F.; Gys, C.; Ito, S.; Konno, S.; Covaci, A.; Kishi, R.; Ikeda, A.
    Science of the Total Environment, 957, 177756, 177756, 2024, [International Magazine]
    English, Scientific journal
  • HBM4EU e-waste study: Occupational exposure of electronic waste workers to phthalates and DINCH in Europe
    Paulien Cleys; Emilie Hardy; Yu Ait Bamai; Giulia Poma; Adam Cseresznye; Govindan Malarvannan; Paul T.J. Scheepers; Susana Viegas; Simo P. Porras; Tiina Santonen; Lode Godderis; Jelle Verdonck; Katrien Poels; Carla Martins; Maria João Silva; Henriqueta Louro; Inese Martinsone; Lāsma Akūlova; An van Nieuwenhuyse; Martien Graumans; Selma Mahiout; Radu Corneliu Duca; Adrian Covaci
    International Journal of Hygiene and Environmental Health, 255, 114286, 114286, Jan. 2024, [International Magazine]
    English, Scientific journal
  • The association between prenatal per-and polyfluoroalkyl substance levels and Kawasaki disease among children of up to 4 years of age: A prospective birth cohort of the Japan Environment and Children's study.
    Hiroyoshi Iwata; Sumitaka Kobayashi; Mariko Itoh; Sachiko Itoh; Rahel Mesfin Ketema; Naomi Tamura; Chihiro Miyashita; Takeshi Yamaguchi; Keiko Yamazaki; Hideyuki Masuda; Yu Ait Bamai; Yasuaki Saijo; Yoshiya Ito; Shoji F Nakayama; Michihiro Kamijima; Reiko Kishi
    Environment international, 183, 108321, 108321, 11 Nov. 2023, [International Magazine]
    English, Scientific journal
  • 北海道スタディ、思春期小児調査からみえる、将来的なNon-communicable Diseasesリスク
    山口 健史; 曾 怡; 池田 敦子; Ketema Rahel Mesfin; アイツバマイ ゆふ; 宮下 ちひろ; 池中 良徳; 今 雅史; 中村 明枝; 岸 玲子
    北海道公衆衛生学雑誌, 37, 1特別付録, 26, 26, 北海道公衆衛生学会, Nov. 2023
    Japanese
  • Exposure to organophosphate flame retardants and plasticizers is positively associated with wheeze and FeNO and eosinophil levels among school-aged children: The Hokkaido study.
    Yi Zeng; Houman Goudarzi; Yu Ait Bamai; Rahel Mesfin Ketema; Maarten Roggeman; Fatima den Ouden; Celine Gys; Chihiro Miyashita; Sachiko Ito; Satoshi Konno; Adrian Covaci; Reiko Kishi; Atsuko Ikeda-Araki
    Environment international, 181, 108278, 108278, Nov. 2023, [International Magazine]
    English, Scientific journal
  • Human exposure to persistent and mobile chemicals: A review of sources, internal levels and health implications
    Da Hye Kim; Yu Ait Bamai; Lidia Belova; Jos Bessems; Giulia Poma; Adrian Covaci
    Science of the Total Environment, 893, 164764, 164764, 01 Oct. 2023, [International Magazine]
    English, Scientific journal
  • Exposure Trends to the Non-phthalate Plasticizers DEHTP, DINCH, and DEHA in Children from 2012 to 2017: The Hokkaido Study.
    Rahel Mesfin Ketema; Monika Kasper-Sonnenberg; Yu Ait Bamai; Chihiro Miyashita; Holger M Koch; Claudia Pälmke; Reiko Kishi; Atsuko Ikeda
    Environmental science & technology, 57, 32, 11926, 11936, 15 Aug. 2023, [International Magazine]
    English, Scientific journal
  • 口唇口蓋裂を有した児の睡眠時間に関する研究 エコチル調査より
    佐藤 遊洋; 西條 泰明; 吉岡 英治; 加藤 育民; 長屋 建; 高橋 悟; 伊藤 善也; 小林 澄貴; アイツバマイ ゆふ; 山崎 圭子; 伊藤 佐智子; 宮下 ちひろ; 池田 敦子; 岸 玲子
    日本衛生学雑誌, 78, Suppl., S206, S206, (一社)日本衛生学会, Mar. 2023
    Japanese
  • 妊婦の母体血中水銀・セレン濃度と4歳までの児の神経発達との関連 エコチル調査
    小林 澄貴; 伊藤 佐智子; 宮下 ちひろ; アイツバマイ ゆふ; 山口 健史; 増田 秀幸; 伊藤 真利子; 山崎 圭子; 田村 菜穂美; ハンリー・シャロン; 池田 敦子; 西條 泰明; 伊藤 善也; 岸 玲子
    日本衛生学雑誌, 78, Suppl., S173, S173, (一社)日本衛生学会, Mar. 2023
    Japanese
  • 前思春期のビスフェノール類曝露と性・ステロイドホルモン値との関連 北海道スタディ
    池田 敦子; 山口 健史; アイツバマイ ゆふ; 池中 良徳; ケテマ・ラヘルメスフィ; 曾 怡; 中村 明枝; 橘田 岳也; 今 雅史; 篠原 信雄; 真部 淳; 宮下 ちひろ; コバチ・アドリアン; 岸 玲子
    日本衛生学雑誌, 78, Suppl., S181, S181, (一社)日本衛生学会, Mar. 2023
    Japanese
  • 化粧品使用による有機フッ素化合物の曝露推計
    藤谷 倫子; 原田 浩二; 増田 秀幸; 山口 健史; アイツバマイ ゆふ; 池田 敦子
    日本衛生学雑誌, 78, Suppl., S200, S200, (一社)日本衛生学会, Mar. 2023
    Japanese
  • 化粧品使用による有機フッ素化合物の曝露推計
    藤谷 倫子; 原田 浩二; 増田 秀幸; 山口 健史; アイツバマイ ゆふ; 池田 敦子
    日本衛生学雑誌, 78, Suppl., S200, S200, (一社)日本衛生学会, Mar. 2023
    Japanese
  • Interpreting biomonitoring data: Introducing the international human biomonitoring (i-HBM) working group's health-based guidance value (HB2GV) dashboard
    Shoji F. Nakayama; Annie St-Amand; Tyler Pollock; Petra Apel; Yu Ait Bamai; Dana Boyd Barr; Jos Bessems; Antonia M. Calafat; Argelia Castaño; Adrian Covaci; Radu Corneliu Duca; Sarah Faure; Karen S. Galea; Sean Hays; Nancy B. Hopf; Yuki Ito; Maryam Zare Jeddi; Marike Kolossa-Gehring; Eva Kumar; Judy S. LaKind; Marta Esteban López; Henriqueta Louro; Kristin Macey; Konstantinos C. Makris; Lisa Melnyk; Aline Murawski; Josh Naiman; Julianne Nassif; Nolwenn Noisel; Devika Poddalgoda; Lesliam Quirós-Alcalá; Ata Rafiee; Loïc Rambaud; Maria João Silva; Jun Ueyama; Marc Andre Verner; Maisarah Nasution Waras; Kate Werry
    International Journal of Hygiene and Environmental Health, 247, 114046, 114046, Jan. 2023, [International Magazine]
    English, Scientific journal
  • Reviewing the variability in urinary concentrations of non-persistent organic chemicals: evaluation across classes, sampling strategies and dilution corrections.
    Maarten Roggeman; Celine Gys; Anna Klimowska; Michiel Bastiaensen; Bartosz Wielgomas; Yu Ait Bamai; Adrian Covaci
    Environmental research, 215, Pt 2, 114332, 114332, Dec. 2022, [International Magazine]
    English, Scientific journal, Various biomonitoring studies have been carried out to investigate the exposure of populations by measuring non-persistent organic chemicals in urine. To accurately assess the exposure, study designs should be carefully developed to maximise reproducibility and achieve good characterization of the temporal variability. To test these parameters, the intraclass correlation coefficients (ICCs) are calculated from repeated measurements and range from poor (<0.4) to excellent (≥0.75). Several studies have reported ICCs based on diverse study designs, but an overview, including recommendations for future studies, was lacking. Therefore, this review aimed to collect studies describing ICCs of non-persistent organic chemicals, discuss variations due to study design and formulate recommendations for future studies. More than 60 studies were selected, considering various chemical classes: bisphenols, pyrethroids, parabens, phthalates, alternative plasticizers and phosphate flame retardants. The variation in ICCs for an individual chemical was high (e.g. ICC of propyl paraben = 0.28-0.91), showing the large impact of the study design and of the specific exposure sources. The highest ICCs were reported for parabens (median = 0.52), while lowest ICCs were for 3-phenoxybenzoic acid (median = 0.08) and bisphenol A (median = 0.20). Overall, chemicals that had an exposure source with high variation, such as the diet, showed lower ICCs than those with more stable exposure sources, such as indoor materials. Urine correction by specific gravity had an overall positive effect on reducing the variability of ICCs. However, this effect was mostly seen in the adult population, while specific compounds showed less variation with creatinine correction. Single samples might not accurately capture the exposure to most non-persistent organic chemicals, especially when small populations are sampled. Future studies that examine compounds with low ICCs should take adequate measures to improve accuracy, such as correcting dilution with specific gravity or collecting multiple samples for one participant.
  • 胎児期フタル酸エステル類曝露による思春期発来への影響 北海道スタディ
    山口 健史; 池田 敦子; アイツバマイ ゆふ; 宮下 ちひろ; 池中 良徳; 中村 明枝; 今 雅史; 藤谷 倫子; 原田 浩二; 岸 玲子
    DOHaD研究, 10, 2, 46, 46, (一社)日本DOHaD学会, Oct. 2022
    Japanese
  • 胎児期フタル酸エステル類曝露による思春期発来への影響 北海道スタディ
    山口 健史; 池田 敦子; アイツバマイ ゆふ; 宮下 ちひろ; 池中 良徳; 中村 明枝; 今 雅史; 藤谷 倫子; 原田 浩二; 岸 玲子
    DOHaD研究, 10, 2, 46, 46, (一社)日本DOHaD学会, Oct. 2022
    Japanese
  • Null Association Between Isolated Orofacial Clefts and Sleep Duration: A Cohort Study From the Japan Environment and Children's Study
    Yukihiro Sato; Eiji Yoshioka; Yasuaki Saijo; Yasuhito Kato; Ken Nagaya; Satoru Takahashi; Yoshiya Ito; Sumitaka Kobayashi; Yu Ait Bamai; Keiko Yamazaki; Sachiko Itoh; Chihiro Miyashita; Atsuko Ikeda-Araki; Reiko Kishi
    The Cleft Palate-Craniofacial Journal, 61, 3, 105566562211284, 105566562211284, SAGE Publications, 26 Sep. 2022, [International Magazine]
    English, Scientific journal
  • Associated congenital anomalies and syndromes of 248 infants with orofacial clefts born between 2011 and 2014 in the Japan Environment and Children's Study
    Yukihiro Sato; Eiji Yoshioka; Yasuaki Saijo; Yasuhito Kato; Ken Nagaya; Satoru Takahashi; Yoshiya Ito; Sumitaka Kobayashi; Yu Ait Bamai; Keiko Yamazaki; Sachiko Itoh; Chihiro Miyashita; Atsuko Ikeda‐Araki; Reiko Kishi; Michihiro Kamijima; Shin Yamazaki; Yukihiro Ohya; Reiko Kishi; Nobuo Yaegashi; Koichi Hashimoto; Chisato Mori; Shuichi Ito; Zentaro Yamagata; Hidekuni Inadera; Takeo Nakayama; Hiroyasu Iso; Masayuki Shima; Hiroshige Nakamura; Narufumi Suganuma; Koichi Kusuhara; Takahiko Katoh
    Congenital Anomalies, 63, 1, 9, 15, Wiley, 23 Sep. 2022, [International Magazine]
    English, Scientific journal, This study aimed to document the complication status of infants with orofacial clefts born between 2011 and 2014 in Japan. This was a descriptive study using data from the Japan Environment and Children's Study. Among 103 060 pregnancies, 248 infants with orofacial clefts were included (livebirth, 239; stillbirth, 4; miscarriage, 5). The items of interest were complication status of orofacial clefts: isolated (typical orofacial clefts only); multi-malformed (orofacial clefts with unrelated major defects); syndromic (orofacial clefts with a syndrome or a chromosomal defect). Regarding the cleft subtypes, of 248 infants with orofacial clefts, 104 had cleft lip with cleft palate (CLP) (41.9%), 68 had cleft lip without cleft palate (CL) (27.4%), 58 had cleft palate without cleft lip (CP) (23.4%), and 18 were nonclassified (7.3%). In infants with CLP, the proportions of isolated, multi-malformed, and syndromic phenotypes were 73.1%, 15.4%, and 11.5%, respectively. In infants with CL, the proportions were 79.4%, 16.2%, and 4.4%, respectively. In infants with CP, the proportions were 69.0%, 13.8%, and 17.2%, respectively. The most frequently associated congenital anomaly was congenital heart disease. In infants with syndromic CLP, 41.7% had trisomy 13. In infants with syndromic CP, 80.0% had the Pierre Robin sequence. Congenital heart disease could be the most frequently associated congenital anomaly. The most frequently associated syndrome could be trisomy 13 in those with CLP and Pierre Robin sequence in those with CP.
  • Maternal dietary folate intake with folic acid supplements and wheeze and eczema in children aged 2 years in the Japan Environment and Children’s Study
    Hideyuki Masuda; Sumitaka Kobayashi; Chihiro Miyashita; Sachiko Itoh; Yu Ait Bamai; Yasuaki Saijo; Yoshiya Ito; Reiko Kishi; Atsuko Ikeda-Araki
    PLOS ONE, 17, 8, e0272968, e0272968, Public Library of Science (PLoS), 22 Aug. 2022, [International Magazine]
    English, Scientific journal, Maternal intake of folic acid supplements is reportedly associated with the risk of early-onset allergies in offspring. However, only a few studies have considered the intake of both folic acid supplements and dietary folate. Here, the relationship between maternal intake of folic acid supplements and allergic symptoms such as wheeze and eczema in offspring was analyzed while considering dietary folate intake. We examined 84,361 mothers and 85,114 children in the Japan Environment and Children’s Study. The participants were divided into three groups depending on maternal folic acid supplementation (“no use,” “occasional use,” and “daily use”). Each group was then subdivided into three groups based on total folic acid and dietary folate intake. Outcomes were determined considering the wheeze and eczema status of each child at the age of 2 years. The status was based on the International Study of Asthma and Allergies in Childhood. It was found that 22.1% of the mothers took folic acid supplements daily. In contrast, 56.3% of the mothers did not take these supplements. Maternal intake of folic acid supplements was not associated with wheeze and eczema in the offspring. In contrast, only dietary folate intake was positively associated with wheeze at the age of 2 (adjusted odds ratio, 1.103; 95% confidence interval, 1.003–1.212). However, there is no scientific evidence of a biological mechanism that clarifies this result. Potential confounders such as other nutrition, outdoor/indoor air pollution, and genetic factors may have affected the results. Therefore, further studies on the association between maternal intake of folic acid and allergic symptoms at the age of 3 or above are needed to confirm the results of this study.

    Trial registration

    UMIN Clinical Trials Registry (number: UMIN000030786)
  • Potential determinants of T helper 2 markers and their distribution in school-aged children
    Houman Goudarzi; Atsuko Ikeda-Araki; Yu Ait Bamai; Sachiko Ito; Tasuku Inao; Isao Yokota; Chihiro Miyashita; Reiko Kishi; Satoshi Konno
    Allergology International, 72, 1, 100, 106, Elsevier BV, Aug. 2022, [International Magazine]
    English, Scientific journal
  • Impact of prenatal exposure to mercury and selenium on neurodevelopmental delay in children in the Japan Environment and Children’s Study using the ASQ-3 questionnaire: a prospective birth cohort
    Sumitaka Kobayashi; Sachiko Itoh; Chihiro Miyashita; Yu Ait Bamai; Takeshi Yamaguchi; Hideyuki Masuda; Mariko Itoh; Keiko Yamazaki; Naomi Tamura; Sharon J.B. Hanley; Atsuko Ikeda-Araki; Yasuaki Saijo; Yoshiya Ito; Miyuki Iwai-Shimada; Shin Yamazaki; Michihiro Kamijima; Reiko Kishi
    Environment International, 168, 107448, 107448, Elsevier BV, Aug. 2022, [International Magazine]
    English, Scientific journal
  • Association between maternal caffeine intake during pregnancy and child development at 6 and 12 months: The Japan Environment and Children's Study
    Shinkichi Nishihara; Sumitaka Kobayashi; Atsuko Ikeda-Araki; Chihiro Miyashita; Sachiko Itoh; Keiko Yamazaki; Yu Ait Bamai; Naomi Tamura; Hideyuki Masuda; Mariko Itoh; Yasuaki Saijo; Yoshiya Ito; Reiko Kishi
    Early Human Development, 171, 105607, 105607, Elsevier BV, Jun. 2022, [International Magazine]
    English, Scientific journal, BACKGROUND: Caffeine intake by pregnant women may have neurodevelopmental effects on the fetus due to adenosine antagonism. However, there are insufficient data and inconsistent results from epidemiological studies on the effect of maternal caffeine intake on child development. AIMS: This study examined the association between mothers' estimated caffeine intake during pregnancy and their children's score on the Japanese version of the Ages & Stages Questionnaires™ (J-ASQ) at 6 and 12 months of age. STUDY DESIGN: The study is a part of nationwide prospective birth-cohort study: the Japan Environment and Children's Study. SUBJECTS: In total, 87,106 participants with the Food Frequency Questionnaire (FFQ) data and J-ASQ at 6 or 12 months of age were included in the study. OUTCOME MEASURES: The data were analyzed by logistic regression analysis to determine whether the scores of the five subscales on the J-ASQ were below the cutoff point as the dependent variable. RESULTS: The results showed that children born to mothers who consumed >300 mg caffeine per day had a 1.11-fold increased odds of gross motor developmental delay at 12 months of age (adjusted odds ratio [AOR] = 1.114 [95 % CI: 1.013-1.226]). CONCLUSIONS: Issues in gross motor development can emerge prior to future developmental issues. Therefore, further studies on developmental outcomes in older children, including the future outcomes of the children who participated in this study, are needed.
  • 日用品中のフタル酸エステル、ビスフェノール等の含有量調査
    原田 浩二; 藤谷 倫子; 呂 兆卿; 増田 秀幸; 山口 健史; アイツバマイ ゆふ; 池田 敦子[荒木]
    日本衛生学雑誌, 77, Suppl., S175, S175, (一社)日本衛生学会, Mar. 2022
    Japanese
  • 思春期のパーソナルケア製品の使用状況:北海道スタディ
    増田 秀幸; アイツバマイ ゆふ; 藤谷 倫子; 山口 健史; 宮下 ちひろ; 岸 玲子; 橘田 岳也; 中村 明枝; 原田 真理子; 原田 浩二; 池田 敦子[荒木]
    日本衛生学雑誌, 77, Suppl., S202, S202, (一社)日本衛生学会, Mar. 2022
    Japanese
  • 思春期のパーソナルケア製品の使用状況:北海道スタディ
    増田 秀幸; アイツバマイ ゆふ; 藤谷 倫子; 山口 健史; 宮下 ちひろ; 岸 玲子; 橘田 岳也; 中村 明枝; 原田 真理子; 原田 浩二; 池田 敦子[荒木]
    日本衛生学雑誌, 77, Suppl., S202, S202, (一社)日本衛生学会, Mar. 2022
    Japanese
  • 学童のプラスチック添加剤への曝露実態 北海道スタディ
    池田 敦子; アイツバマイ ゆふ; Ketema Rahel Mesfin; Gys Celine; Bastiaensen Michiel; Covaci Adrian; 岸 玲子
    日本衛生学雑誌, 77, Suppl., S206, S206, (一社)日本衛生学会, Mar. 2022
    Japanese
  • Nonylphenol exposure in 7-year-old Japanese children between 2012 and 2017- Estimation of daily intakes based on novel urinary metabolites.
    Benedikt Ringbeck; Daniel Bury; Atsuko Ikeda-Araki; Yu Ait Bamai; Rahel Mesfin Ketema; Chihiro Miyashita; Thomas Brüning; Reiko Kishi; Holger M Koch
    Environment international, 161, 107145, 107145, Mar. 2022, [International Magazine]
    English, Scientific journal, Nonylphenol (NP) has been under scrutiny for decades due to its endocrine-disrupting properties and its ubiquity in the environment. Despite its widespread occurrence, robust and reliable exposure data are rare. In this study, we used human biomonitoring (HBM) measuring the novel urinary alkyl-chain-oxidized biomarkers OH-NP and oxo-NP to determine NP exposure in 7-year-old Japanese children. The new biomarkers are advantageous over measuring unchanged NP because they are not prone to external contamination. We analyzed 180 first morning void urine samples collected between 2012 and 2017. OH-NP and oxo-NP were detected in 100% and 66% of samples at median concentrations of 2.69 and 0.36 µg/L, respectively. 10-fold concentration differences between OH-NP and oxo-NP are in line with recent findings on human NP metabolism. Based on OH-NP we back-calculated median and maximum NP daily intakes (DI) of 0.14 and 0.95 µg/(kg bw*d). These DIs are rather close to but still below the current provisional tolerable daily intake of 5 µg/(kg bw*d) by the Danish Environmental Protection Agency. Between 2012 and 2017 the DIs decreased by an average of 4.7% per year. We observed no seasonal changes or gender differences and questionnaire data on food consumption, housing characteristics or pesticide use showed no clear associations with NP exposure. Urinary OH-NP was weakly associated with the oxidative stress (lipid peroxidation) biomarkers N-ε-hexanoyl-lysine (HEL) and trans-4-hydroxy-2-nonenal (HNE) (Spearman ρ = 0.30 and 0.22, respectively), but not with 8-hydroxy-2'-deoxyguanosine (8-OHdG). Further research is needed to identify and understand the major sources of NP exposure and to investigate a potential role in oxidative stress. This study is the first to investigate NP exposure in Japanese children based on robust and sensitive HBM data. It is a first step to fill the long-standing gap in quantitative human NP exposure monitoring and risk assessment.
  • Phthalates mixture on allergies and oxidative stress biomarkers among children: The Hokkaido study.
    Rahel Mesfin Ketema; Yu Ait Bamai; Chihiro Miyashita; Takeshi Saito; Reiko Kishi; Atsuko Ikeda-Araki
    Environment international, 160, 107083, 107083, Feb. 2022, [International Magazine]
    English, Scientific journal, BACKGROUND: Exposure to individual phthalates and the mediation effect of oxidative stress in association with asthma and allergic symptoms have been studied previously. Little is known about the mixture effect of phthalates on health outcomes. Thus, we investigated the effect of a mixture of ten phthalate metabolites in association with wheeze, rhino-conjunctivitis, and eczema. The mediating effect of three oxidative stress biomarkers was also assessed. METHODS: Levels of 10 phthalate metabolites and 3 oxidative stress biomarkers were measured in 386 urine samples from 7-year-old children. Parents reported demographic and allergic symptoms using ISAAC questionnaires. Logistic regression for individual metabolites and mixture analysis weighted quantile sum (WQS) and Bayesian kernel machine regression (BKMR) were fitted to examine the association between phthalate metabolite exposure and health outcomes. Baron and Kenny's regression approach was used for mediation analysis. RESULTS: In logistic regression model showed mono (2-ethyl-5-carboxypentyl) phthalate (MECPP) (OR = 1.41, 95% CI 1.02-1.97) and mono carboxy-isononyl phthalate (cx-MINP) (OR = 1.40, 95% CI 1.07-1.86) were associated with wheeze. The WQS index had a significant association (OR = 1.46, 95% CI 1.09-1.96) with wheeze and (OR = 1.40, 95% CI 1.07-1.82) with eczema. Mono-isononyl phthalate (MINP) and mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP) were the most highly weighted metabolites. In the BKMR model, diisononyl phthalate (DINP) metabolites showed the highest group posterior inclusion probability (PIP). Among DINP metabolites, MINP in wheeze, cx-MINP in rhino-conjunctivitis and OH-MINP in eczema showed the highest conditional PIPs. The overall metabolites mixture effect was associated with eczema. We did not find any mediation of oxidative stress in the association between phthalates and symptoms. No significant association between phthalate metabolites and oxidative stress was observed in this study. CONCLUSION: Mixture of phthalate metabolites were associated with wheeze and eczema. The main contributors to the association were DEHP and DINP metabolites. No mediation of oxidative stress was observed.
  • Relations of mold, stove, and fragrance products on childhood wheezing and asthma: A prospective cohort study from the Japan Environment and Children's Study
    Yasuaki Saijo; Eiji Yoshioka; Yukihiro Sato; Hiroshi Azuma; Yusuke Tanahashi; Yoshiya Ito; Sumitaka Kobayashi; Machiko Minatoya; Yu Ait Bamai; Keiko Yamazaki; Sachiko Itoh; Chihiro Miyashita; Atsuko Ikeda‐Araki; Reiko Kishi; Michihiro Kamijima; Shin Yamazaki; Yukihiro Ohya; Nobuo Yaegashi; Koichi Hashimoto; Chisato Mori; Shuichi Ito; Zentaro Yamagata; Hidekuni Inadera; Takeo Nakayama; Hiroyasu Iso; Masayuki Shima; Youichi Kurozawa; Narufumi Suganuma; Koichi Kusuhara; Takahiko Katoh
    Indoor Air, 32, 1, e12931, Wiley, Jan. 2022, [International Magazine]
    English, Scientific journal, This prospective cohort study aimed to examine the associations between mold growth, type of stoves, and fragrance materials and early childhood wheezing and asthma, using data from the Japan Environment and Children's Study. Mold growth at home, usage of kerosene/gas stove, wood stove/fireplace, and air freshener/deodorizer were surveyed using a questionnaire at 1.5-year-old, and childhood wheezing and doctor-diagnosed asthma during the previous year were obtained using a 3-year-old questionnaire. Multilevel logistic regression analysis was performed to evaluate the association between exposure to childhood wheezing and asthma. A total of 60 529 children were included in the analysis. In multivariate analyses, mold growth and wood stove/fireplace had significantly higher odds ratios (ORs) for wheezing (mold growth: 1.13; 95% CI, 1.06-1.22; wood stove/fireplace: 1.23; 95% CI, 1.03-1.46). All four exposures had no significant ORs for childhood doctor-diagnosed asthma; however, in the supplemental analysis of northern regions, wood stove/fireplace had a significantly higher OR for asthma. Mold growth and wood stove/fireplace had significant associations with childhood wheezing in the northern regions. Mold elimination in the dwellings and use of clean heating (no air pollution emissions) should be taken into consideration to prevent and improve childhood wheezing and asthma.
  • The association between prenatal perfluoroalkyl substance exposure and symptoms of attention-deficit/hyperactivity disorder in 8-year-old children and the mediating role of thyroid hormones in the Hokkaido study
    Sachiko Itoh; Keiko Yamazaki; Satoshi Suyama; Atsuko Ikeda-Araki; Chihiro Miyashita; Yu Ait Bamai; Sumitaka Kobayashi; Hideyuki Masuda; Takeshi Yamaguchi; Houman Goudarzi; Emiko Okada; Ikuko Kashino; Takuya Saito; Reiko Kishi
    Environment International, 159, 107026, 107026, Elsevier BV, Jan. 2022, [International Magazine]
    English, Scientific journal, BACKGROUND: Disruption of thyroid hormone (TH) levels during pregnancy contributes to attention deficit hyperactivity disorder (ADHD). Exposure to perfluoroalkyl substances (PFAS) during gestation may affect levels of maternal and neonatal TH; however, little is known about the effect of PFAS on ADHD mediated by TH. OBJECTIVES: We investigated the impact of maternal PFAS exposure on children's ADHD symptoms with the mediating effect of TH. METHODS: In a prospective birth cohort (the Hokkaido study), we included 770 mother-child pairs recruited between 2002 and 2005 for whom both prenatal maternal and cord blood samples were available. Eleven PFAS were measured in maternal serum obtained at 28-32 weeks of gestation using ultra-performance liquid chromatography coupled with triple quadrupole tandem mass spectrometry. TH and thyroid antibody, including thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), free thyroxine (FT4), thyroid peroxidase antibody (TPOAb), and thyroglobulin antibody (TgAb) were measured in maternal blood during early pregnancy (median 11 gestational weeks) and in cord blood at birth. ADHD symptoms in the children at 8 years of age were rated by their parents using the ADHD-Rating Scale (ADHD-RS). The cut-off value was set at the 80th percentile for each sex. RESULTS: Significant inverse associations were found between some PFAS in maternal serum and ADHD symptoms among first-born children. Assuming causality, we found only one significant association: maternal FT4 mediated 17.6% of the estimated effect of perfluoroundecanoic acid exposure on hyperactivity-impulsivity among first-born children. DISCUSSION: Higher PFAS levels in maternal serum during pregnancy were associated with lower risks of ADHD symptoms at 8 years of age. The association was stronger among first-born children in relation to hyperactivity-impulsivity than with regard to inattention. There was little mediating role of TH during pregnancy in the association between maternal exposure to PFAS and reduced ADHD symptoms at 8 years of age.
  • 一般家庭における短期/長期堆積ダストを活用したSVOCの曝露評価研究1 リン系難燃剤・可塑剤の室内濃度分布と汚染要因の解析
    戸次 加奈江; 池田 敦子; アイツバマイ ゆふ; 稲葉 洋平; 東 賢一; 金 勲; 岸 玲子
    室内環境学会学術大会講演要旨集, 2021年, 100, 101, (一社)室内環境学会, Dec. 2021
    Japanese
  • 一般家庭における短期/長期堆積ダストを活用したSVOCの曝露評価研究2 子どものハウスダスト中リン系難燃剤・可塑剤の一日摂取量
    池田 敦子; 戸次 加奈江; アイツバマイ ゆふ; 稲葉 洋平; 金 勲; 岸 玲子
    室内環境学会学術大会講演要旨集, 2021年, 102, 103, (一社)室内環境学会, Dec. 2021
    Japanese
  • 室内空気中SVOC(準揮発性有機化合物)濃度の実態調査
    金 勲; 稲葉 洋平; 戸次 加奈江; 東 賢一; 林 基哉; 荒木 敦子; アイツバマイ ゆふ; 篠原 直秀; 欅田 尚樹
    室内環境学会学術大会講演要旨集, 2021年, 104, 105, (一社)室内環境学会, Dec. 2021
    Japanese
  • 一般家庭における短期/長期堆積ダストを活用したSVOCの曝露評価研究1 リン系難燃剤・可塑剤の室内濃度分布と汚染要因の解析
    戸次 加奈江; 池田 敦子; アイツバマイ ゆふ; 稲葉 洋平; 東 賢一; 金 勲; 岸 玲子
    室内環境学会学術大会講演要旨集, 2021年, 100, 101, (一社)室内環境学会, Dec. 2021
    Japanese
  • 一般家庭における短期/長期堆積ダストを活用したSVOCの曝露評価研究2 子どものハウスダスト中リン系難燃剤・可塑剤の一日摂取量
    池田 敦子; 戸次 加奈江; アイツバマイ ゆふ; 稲葉 洋平; 金 勲; 岸 玲子
    室内環境学会学術大会講演要旨集, 2021年, 102, 103, (一社)室内環境学会, Dec. 2021
    Japanese
  • Hypertensive Disorders during Pregnancy and Anthropometric Measurement of Children up to 7 Years of Age: The Hokkaido Birth Cohort Study in Japan.
    Kritika Poudel; Sumitaka Kobayashi; Chihiro Miyashita; Takeshi Yamaguchi; Naomi Tamura; Atsuko Ikeda-Araki; Yu Ait Bamai; Sachiko Itoh; Keiko Yamazaki; Hideyuki Masuda; Mariko Itoh; Reiko Kishi
    International journal of environmental research and public health, 18, 20, 18 Oct. 2021, [International Magazine]
    English, Scientific journal, Hypertensive disorders during pregnancy (HDP) increase the risk of offspring with a low birth weight, preterm birth and small-for-gestational age; however, evidence of the anthropometric measurements during early childhood remains limited. We aimed to understand the associations between maternal HDP and anthropometric measurements of children aged up to seven years in a Japanese cohort. In total, 20,926 mother-infant pairs participated in the Hokkaido Study on Environment and Children's Health, Japan, from 2002 to 2013. Medical reports were used to confirm HDP exposure, while weight, height, height z score, and weight z score were the outcomes. The prevalence of HDP in the study population was 1.7%. The birth height of male children born to HDP mothers was smaller as compared to those born to non-HDP mothers. When adjusted with covariates, the linear regressions showed significant changes in birth weight (β: -79.3; 95% confidence interval [CI]: -154.8, -3.8), birth height (-0.67; 95% CI: -1.07, -0.26), weight at seven years (1.21; 95% CI: 0.13, 2.29), and weight gain between four and seven years (1.12; 95% CI: 0.28, 1.96) of male children exposed to HDP. Differences were more significant in male children than female. Our study showed that despite low birth weight, male children exposed to HDP caught up with their growth and gained more weight by seven years of age compared with male children not exposed to HDP, whereas no such differences were observed in female children; however, this finding requires replication.
  • Association between the Concentrations of Metallic Elements in Maternal Blood during Pregnancy and Prevalence of Abdominal Congenital Malformations: The Japan Environment and Children's Study.
    Chihiro Miyashita; Yasuaki Saijo; Yoshiya Ito; Atsuko Ikeda-Araki; Sachiko Itoh; Keiko Yamazaki; Sumitaka Kobayashi; Yu Ait Bamai; Hideyuki Masuda; Naomi Tamura; Mariko Itoh; Takeshi Yamaguchi; Shin Yamazaki; Reiko Kishi; The Japan Environment And Children's Study Group
    International journal of environmental research and public health, 18, 19, 26 Sep. 2021, [International Magazine]
    English, Scientific journal, Abdominal congenital malformations are responsible for early mortality, inadequate nutrient intake, and infant biological dysfunction. Exposure to metallic elements in utero is reported to be toxic and negatively impacts ontogeny. However, no prior study has sufficiently evaluated the effects of exposure to metallic elements in utero on abdominal congenital malformations. The aim of the present study was to evaluate associations between metallic elements detected in maternal blood during pregnancy and congenital abdominal malformations. Data from participants in the Japan Environment and Children's Study was used in the present study, and contained information on singleton and live birth infants without congenital abnormalities (control: n = 89,134) and abdominal malformations (case: n = 139). Heavy metals such as mercury (Hg), lead (Pb), cadmium (Cd), and trace elements of manganese (Mn) and selenium (Se) were detected in maternal serum samples during mid- and late-gestation. Infant congenital abnormalities were identified from delivery records at birth or one month after birth by medical doctors. In a multivariate analysis adjusted to account for potential confounders, quartiles of heavy metals and trace elements present in maternal blood were not statistically correlated to the prevalence of abdominal congenital malformations at birth. This study is the first to reveal the absence of significant associations between exposure levels to maternal heavy metals and trace elements in utero and the prevalence of abdominal congenital malformations in a large cohort of the Japanese population. Further studies are necessary to investigate the impact of exposure to heavy metals and trace elements via maternal blood in offspring after birth.
  • Maternal psychological distress, education, household income, and congenital heart defects: a prospective cohort study from the Japan environment and children's study.
    Yasuaki Saijo; Eiji Yoshioka; Yukihiro Sato; Hiroshi Azuma; Yusuke Tanahashi; Yoshiya Ito; Sumitaka Kobayashi; Machiko Minatoya; Yu Ait Bamai; Keiko Yamazaki; Sachiko Itoh; Chihiro Miyashita; Atsuko Ikeda-Araki; Reiko Kishi
    BMC pregnancy and childbirth, 21, 1, 544, 544, 07 Aug. 2021, [International Magazine]
    English, Scientific journal, BACKGROUND: The influence of maternal psychological distress on infant congenital heart defects (CHDs) has not been thoroughly investigated. Furthermore, there have been no reports on the combined effect of maternal psychological distress and socioeconomic status on infant CHDs. This study aimed to examine whether maternal psychological distress, socioeconomic status, and their combinations were associated with CHD. METHODS: We conducted a prospective cohort study using data from the Japan Environment and Children's Study, which recruited pregnant women between 2011 and 2014. Maternal psychological distress was evaluated using the Kessler Psychological Distress Scale in the first trimester, while maternal education and household income were evaluated in the second and third trimesters. The outcome of infant CHD was determined using the medical records at 1 month of age and/or at birth. Crude- and confounder-adjusted logistic regression analyses were performed to evaluate the association between maternal psychological distress and education and household income on infant CHD. RESULTS: A total of 93,643 pairs of mothers and infants were analyzed, with 1.1% of infants having CHDs. Maternal psychological distress had a significantly higher odds ratio in the crude analysis but not in the adjusted analysis, while maternal education and household income were statistically insignificant. In the analysis of the combination variable of lowest education and psychological distress, the P for trend was statistically significant in the crude and multivariate model excluding anti-depressant medication, but the significance disappeared in the full model (P = 0.050). CONCLUSIONS: The combination of maternal psychological distress and lower education may be a possible indicator of infant CHD.
  • Association between Early Life Child Development and Family Dog Ownership: A Prospective Birth Cohort Study of the Japan Environment and Children's Study.
    Machiko Minatoya; Atsuko Ikeda-Araki; Chihiro Miyashita; Sachiko Itoh; Sumitaka Kobayashi; Keiko Yamazaki; Yu Ait Bamai; Yasuaki Saijo; Yukihiro Sato; Yoshiya Ito; Reiko Kishi; The Japan Environment And Children's Study Group
    International journal of environmental research and public health, 18, 13, 02 Jul. 2021, [International Magazine]
    English, Scientific journal, Pets may play a role in the social-emotional development of children. In particular, some studies have suggested that family dog ownership is associated with better health outcomes. To date, no study has assessed child development in association with dog ownership of different time points. The purpose of the current study was primary to investigate whether "ever" family dog ownership was associated with early child development, and secondary to further examine whether associations between family dog ownership and early child development differ among family dog ownership of status, including "past only", "current only", and "always" groups, using the data of family dog ownership obtained at multiple time points. Associations between family dog ownership and infant development at 3 years of age were examined using data from a nationwide prospective birth cohort study, the Japan Environment and Children's Study (n = 78,941). "Ever" family dog ownership was categorized to "past only", "current only", and "always". We observed that children with "ever" family dog ownership showed a significantly decreased risk of developmental delay in the communication (odds ratio [OR] = 0.87; 95% confidence interval [CI]: 0.78, 0.96), gross motor (OR = 0.83; 95% CI: 0.76, 0.92), problem-solving (OR = 0.89; 95% CI: 0.83, 0.96) and personal-social (OR = 0.86; 95% CI: 0.72, 0.92) domains compared to children with "never" family dog ownership. Furthermore, a significantly decreased risk of developmental delay in gross motor function was observed in association with living with dogs in the "past only" (OR = 0.83; 95% CI: 0.73, 0.95) and "always" (OR = 0.86; 95% CI: 0.75, 0.98). In addition, a decreased risk of developmental delay in the problem-solving domain was associated with "past" family dog ownership (OR = 0.87; 95% CI: 0.79, 0.97) and in the personal-social domain was associated with "always" family dog ownership (OR = 0.81; 95% CI = 0.68, 0.95). Given the possible positive association between early life child development and family dog ownership, living with dogs may be an important factor to be considered when assessing child development.
  • Hokkaido birth cohort study on environment and children's health: cohort profile 2021.
    Reiko Kishi; Atsuko Ikeda-Araki; Chihiro Miyashita; Sachiko Itoh; Sumitaka Kobayashi; Yu Ait Bamai; Keiko Yamazaki; Naomi Tamura; Machiko Minatoya; Rahel Mesfin Ketema; Kritika Poudel; Ryu Miura; Hideyuki Masuda; Mariko Itoh; Takeshi Yamaguchi; Hisanori Fukunaga; Kumiko Ito; Houman Goudarzi
    Environmental health and preventive medicine, 26, 1, 59, 59, 22 May 2021, [International Magazine]
    English, Scientific journal, BACKGROUND: The Hokkaido Study on Environment and Children's Health is an ongoing study consisting of two birth cohorts of different population sizes: the Sapporo cohort and the Hokkaido cohort. Our primary objectives are to (1) examine the effects that low-level environmental chemical exposures have on birth outcomes, including birth defects and growth retardation; (2) follow the development of allergies, infectious diseases, and neurobehavioral developmental disorders, as well as perform a longitudinal observation of child development; (3) identify high-risk groups based on genetic susceptibility to environmental chemicals; and (4) identify the additive effects of various chemicals, including tobacco. METHODS: The purpose of this report is to provide an update on the progress of the Hokkaido Study, summarize recent results, and suggest future directions. In particular, this report provides the latest details from questionnaire surveys, face-to-face examinations, and a collection of biological specimens from children and measurements of their chemical exposures. RESULTS: The latest findings indicate different risk factors of parental characteristics on birth outcomes and the mediating effect between socioeconomic status and children that are small for the gestational age. Maternal serum folate was not associated with birth defects. Prenatal chemical exposure and smoking were associated with birth size and growth, as well as cord blood biomarkers, such as adiponectin, leptin, thyroid, and reproductive hormones. We also found significant associations between the chemical levels and neuro development, asthma, and allergies. CONCLUSIONS: Chemical exposure to children can occur both before and after birth. Longer follow-up for children is crucial in birth cohort studies to reinforce the Developmental Origins of Health and Disease hypothesis. In contrast, considering shifts in the exposure levels due to regulation is also essential, which may also change the association to health outcomes. This study found that individual susceptibility to adverse health effects depends on the genotype. Epigenome modification of DNA methylation was also discovered, indicating the necessity of examining molecular biology perspectives. International collaborations can add a new dimension to the current knowledge and provide novel discoveries in the future.
  • Secular trends of urinary phthalate metabolites in 7-year old children and association with building characteristics: Hokkaido study on environment and children's health.
    Rahel Mesfin Ketema; Yu Ait Bamai; Atsuko Ikeda-Araki; Takeshi Saito; Reiko Kishi
    International journal of hygiene and environmental health, 234, 113724, 113724, May 2021, [International Magazine]
    English, Scientific journal, The widespread commercial production and use of phthalates as plasticizers in consumer products have led to significant human exposure. Some phthalates are known to disrupt the endocrine system and result in adverse health outcomes. As such, they have been regulated in materials used for children's items and food packages. In this study, we examined the secular trend of urinary phthalate metabolites in children and the association between metabolites and building characteristics. In total, 400 first-morning spot urine samples of 7 years old children collected from 2012 to 2017 from an ongoing birth cohort study were examined. Parents provided information on demographics and building questionnaires. We analyzed 10 urinary phthalate metabolites from five phthalate diesters using ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS): MiBP, MnBP, MBzP, MEHP, MEOHP, MEHHP, MECPP, MiNP, OH-MiNP, and cx-MiNP. A multivariable regression model with creatinine-corrected metabolite levels was applied to assess secular trends during 2012-2017. The association between metabolite levels and building characteristics was investigated using a mutual-adjusted linear regression. The metabolites MnBP, MEHP, MEOHP, MEHHP, MECPP, and OH-MiNP were detected in all samples. The highest median concentration was for MECPP 37.4 ng/mL, followed by MnBP and MEHHP at concentrations of 36.8 and 25.8 ng/mL, respectively. Overall, DBP, BBzP, and DINP metabolite concentrations in this study were comparable to or lower than those in previous studies from Japan and other countries in a similar study period. Higher concentrations of DEHP metabolites were observed in this study than in children from the USA and Germany, as per previous reports. Despite updated phthalate regulations and reports of production volume change in Japan, all the measured metabolites showed a stable trend between 2012 and 2017. Higher phthalate metabolite levels were observed among children from households with low annual income, those who lived in old buildings, and those with window opening habits of ≥1 h than ≤1 h. In contrast, children in houses that vacuumed 4 or more days/week showed a lower level of MnBP than those in houses that vacuumed ≤3 days/week. This study demonstrates that the internal exposure level of phthalates in Japanese children was stable from 2012 to 2017. Our findings suggest that phthalate exposure in children is consistent. Thus, improvements in the indoor environment, such as frequent vacuuming, may reduce exposure. Biomonitoring of phthalates is critical for elucidating their possible health effects and developing mitigation strategies.
  • Prevalence of childhood wheeze and modified DNA methylation at 7 years of age according to maternal folate levels during pregnancy in the Hokkaido Study.
    Chihiro Miyashita; Atsuko Araki; Ryu Miura; Yu Ait Bamai; Sumitaka Kobayashi; Sachiko Itoh; Kumiko Ito; Meng-Shan Tsai; Reiko Kishi
    Pediatric allergy and immunology : official publication of the European Society of Pediatric Allergy and Immunology, 32, 3, 514, 523, Apr. 2021, [International Magazine]
    English, Scientific journal, BACKGROUND: A high dose of folic acid during pregnancy may increase the risk of asthma, wheezing, and respiratory disease in childhood. Folate acid can modify inflammation and immune susceptibility of offspring with some epigenetic differentiation, including DNA methylation. This study evaluated associations between maternal folate levels during pregnancy and childhood wheezing; furthermore, the study assessed whether maternal folate-modified DNA methylation is related to asthma. Methods Participants in the current study were 6651 mother-child pairs who had complete data on characteristics and who had completed at least one of the International Study of Asthma and Allergies in Childhood questionnaires when the child was 1, 2, 4, and 7 years of age. Moreover, a case-control study to assess DNA methylation at 7 years of age was conducted among 136 children who experienced wheezing and a control group of 139 children with no history of allergies. Results The median of maternal serum was 16.76 nmol/L, assayed by chemiluminescent immunoassay. We found significantly increased adjusted odds ratios of childhood wheezing at 2 years age according to maternal folate levels, compared with the lowest folate quartile (odds ratio [95% confidence interval] = highest; 1.27 [1.03, 1.56], and second, 1.27 [1.05, 1.55]); however, no changes were observed at 1, 4, and 7 years of age. In a case-control study, no association of maternal folate levels with DNA methylation was observed. Conclusion Our results suggest that maternal folate did not affect persistent wheezing in school-aged children, or DNA methylation of gasdermin B, orosomucoid-like 3, and Ikaros family zinc finger 3 at 7 years of age.
  • Hypertensive Disorders during Pregnancy (HDP), Maternal Characteristics, and Birth Outcomes among Japanese Women: A Hokkaido Study.
    Kritika Poudel; Sumitaka Kobayashi; Chihiro Miyashita; Atsuko Ikeda-Araki; Naomi Tamura; Yu Ait Bamai; Sachiko Itoh; Keiko Yamazaki; Hideyuki Masuda; Mariko Itoh; Kumiko Ito; Reiko Kishi
    International journal of environmental research and public health, 18, 7, 24 Mar. 2021, [International Magazine]
    English, Scientific journal, Hypertension during pregnancy causes a greater risk of adverse birth outcomes worldwide; however, formal evidence of hypertensive disorders during pregnancy (HDP) in Japan is limited. We aimed to understand the association between maternal characteristics, HDP, and birth outcomes. In total, 18,833 mother-infant pairs were enrolled in the Hokkaido study on environment and children's health, Japan, from 2002 to 2013. Medical records were used to identify hypertensive disorders and birth outcomes, namely, small for gestational age (SGA), SGA at full term (term-SGA), preterm birth (PTB), and low birth weight (LBW). The prevalence of HDP was 1.9%. Similarly, the prevalence of SGA, term-SGA, PTB, and LBW were 7.1%, 6.3%, 7.4%, and 10.3%, respectively. The mothers with HDP had increased odds of giving birth to babies with SGA (2.13; 95% Confidence Interval (CI): 1.57, 2.88), PTB (3.48; 95%CI: 2.68, 4.50), LBW (3.57; 95%CI: 2.83, 4.51) than normotensive pregnancy. Elderly pregnancy, low and high body mass index, active and passive smoking exposure, and alcohol consumption were risk factors for different birth outcomes. Therefore, it is crucial for women of reproductive age and their families to be made aware of these risk factors through physician visits, health education, and various community-based health interventions.
  • Lower respiratory tract infections and orofacial clefts: a prospective cohort study from the Japan Environment and Children's Study.
    Yukihiro Sato; Eiji Yoshioka; Yasuaki Saijo; Toshinobu Miyamoto; Hiroshi Azuma; Yusuke Tanahashi; Yoshiya Ito; Sumitaka Kobayashi; Machiko Minatoya; Yu Ait Bamai; Keiko Yamazaki; Sachiko Ito; Chihiro Miyashita; Atsuko Araki; Reiko Kishi
    Journal of epidemiology, 32, 6, 270, 276, 13 Jan. 2021, [Domestic magazines]
    English, Scientific journal, BACKGROUND: Lower respiratory tract infections (LRTIs) are a cause of inpatient and outpatient care among children. Although orofacial clefts seem to be associated with LRTIs, epidemiological studies are scarce on this topic. This study aimed to examine whether infants with orofacial clefts were associated with LRTIs. METHODS: This prospective cohort study used data from the Japan Environment and Children's Study, whose baseline recruitment was conducted during 2011-2014. This study included 81,535 participants. The number of infants with cleft lip and palate (CLP), cleft lip (CL), and cleft palate only (CP) was 67, 49, and 36, respectively. We defined history of LRTIs until 12 months' age reported by their mothers as the dependent variable. Accumulated breastfeeding duration was used as potential mediators. RESULTS: The incidence proportion of LRTIs among the control group was 6.0%. The incidence proportion among infants with CLP, CL, and CP were 11.9%, 14.3%, and 5.6%, respectively. After adjusting for covariates, compared with the control group, infants with CLP and CL were associated with risk of LRTIs (incidence risk ratio [IRR] of CLP = 2.38 [95% confidence interval = 1.30, 4.36] and of CL = 2.73 [1.40, 5.33]) , but not ones with CP (1.08 [0.28, 4.15]). Accumulated breastfeeding duration decreased the IRR of CLP only (IRR of CLP = 2.16 [1.19, 3.93]). CONCLUSIONS: Infants with orofacial clefts aged 1 year have a potentially high incidence proportion of LRTIs. Accumulated breastfeeding duration might mediate the associations of CLP.
  • Short-term variability of bisphenols in spot, morning void and 24-hour urine samples.
    Celine Gys; Michiel Bastiaensen; Govindan Malarvannan; Yu Ait Bamai; Atsuko Araki; Adrian Covaci
    Environmental pollution (Barking, Essex : 1987), 268, Pt A, 115747, 115747, 01 Jan. 2021, [International Magazine]
    English, Scientific journal, Due to worldwide regulations on the application of the high production volume industrial chemical bisphenol A (BPA) in various consumer products, alternative bisphenols such as bisphenol F (BPF) and bisphenol S (BPS) are increasingly used. To assess human exposure to these chemicals, biomonitoring of urinary concentrations is frequently used. However, the short-term variability of alternative bisphenols has not been evaluated thoroughly yet, which is essential to achieve a correct estimation of exposure. In this study, we collected all spot urine samples from ten healthy adults for five consecutive days, and an additional 24 h pooled sample. We measured the concentrations of seven bisphenols (BPAF, BPF, BPA, BPB, BPZ, BPS and BPAP) in these samples using gas chromatography coupled to tandem mass spectrometry. BPA, BPF and BPS were frequently found in spot samples (>80%), while bisphenol AP (BPAP) was detected in 43% of spot samples. Calculations of intra-class correlation coefficients (ICCs) showed that reproducibility of these four bisphenols was relatively poor (<0.01-0.200) but improved when concentrations were corrected for urine dilution using creatinine levels (0.128-0.401). Of these four bisphenols, BPF showed the best reproducibility (ICC 0.200-0.439) and BPS the most variability (ICC <0.01-0.128). In general, the within-participant variability of bisphenol levels was the largest contributor to the total variance (47-100%). We compared repeated first morning voids to 24 h pooled urine and found no significantly different concentrations for BPA, BPF, BPS, or BPAP. Levels of BPA and BPF differed significantly depending on the sampling time throughout the day. The findings in this study suggest that collecting multiple samples per participant over a few days, in predefined time windows throughout the day, could result in a more reliable estimation of internal exposure to bisphenols.
  • Short-term temporal variability of urinary biomarkers of organophosphate flame retardants and plasticizers.
    Michiel Bastiaensen; Celine Gys; Govindan Malarvannan; Mihai Fotache; Jasper Bombeke; Yu Ait Bamai; Atsuko Araki; Adrian Covaci
    Environment international, 146, 106147, 106147, Jan. 2021, [International Magazine]
    English, Scientific journal, BACKGROUND: Exposure to organophosphate flame retardants and plasticizers (PFRs) is commonly estimated by measuring biomarker concentrations in spot urine samples. However, their concentrations in urine can vary greatly over time due to short biological half-lives and variable exposure, potentially leading to exposure misclassification. In this study, we examined the within- and between-individual and within- and between-day variability of PFR metabolites in spot and 24-hour pooled urine samples during five consecutive days. METHODS: We collected all spot urine samples from 10 healthy adults for 5 days. On one additional day, we collected 24-hour pooled urine samples. Samples were analyzed by solid-phase extraction coupled to high-performance liquid chromatography tandem mass spectrometry. We calculated intraclass correlation coefficients (ICCs) to assess the reproducibility of metabolite concentrations in morning void and spot samples. RESULTS: Fair-to-good reproducibility was observed for serial measurements of bis(1,3-dichloro-2-propyl) phosphate (BDCIPP), 1-hydroxy-2-propyl bis(1-chloro-2-propyl) phosphate (BCIPHIPP), 2-hydroxyethyl bis(2-butoxyethyl) phosphate (BBOEHEP) and 2-ethyl-5-hydroxyhexyl diphenyl phosphate (5-HO-EHDPHP) (ICC: 0.396 - 0.599), whereas concentrations of diphenyl phosphate (DPHP) and 2-ethylhexyl phenyl phosphate (EHPHP) were more variable in time (ICC: 0.303 and 0.234). Reproducibility improved significantly when only morning void samples were considered and when concentrations were adjusted for urinary dilution. Collecting 24-hour pooled urine could be a reliable alternative for PFR biomarkers with poor short-term temporal variability. CONCLUSIONS: The between-day variability was minor compared to variability observed within the same day, which suggests that collecting multiple samples could reduce exposure missclassification. Differences in the observed between- and within-individual variance were compound specific and related to both the nature of the exposure (e.g., diet vs other exposure routes, multiple sources) and the individual toxicokinetic properties of the investigated PFRs.
  • Parental educational level and childhood wheezing and asthma: A prospective cohort study from the Japan Environment and Children's Study.
    Yasuaki Saijo; Eiji Yoshioka; Yukihiro Sato; Toshinobu Miyamoto; Hiroshi Azuma; Yusuke Tanahashi; Yoshiya Ito; Sumitaka Kobayashi; Machiko Minatoya; Yu Ait Bamai; Keiko Yamazaki; Sachiko Itoh; Chihiro Miyashita; Atsuko Araki; Reiko Kishi
    PloS one, 16, 4, e0250255, 2021, [International Magazine]
    English, Scientific journal, BACKGROUND: The influence of mothers' and fathers' educational levels in separate evaluations of asthma has not been fully investigated. This study aims to examine the associations of the mother's and fathers' educational levels with childhood wheeze and asthma adjusting for crude and pre-and post-natal modifiable risk factors. METHODS: We conducted a prospective cohort study using data from the Japan Environment and Children's Study, which recruited pregnant women from 2011 to 2014. The mother's and father's educational levels were surveyed by a questionnaire during the pregnancy, and childhood wheezing and doctor-diagnosed asthma were estimated using a 3-year questionnaire. Multilevel logistic regression analysis was performed to evaluate the association between the mother's and father's educational levels and childhood wheezing and asthma, adjusted for pre-and post-natal factors. RESULTS: A total of 69,607 pairs of parents and their single infants were analyzed. We found 17.3% of children had wheezing and 7.7% had asthma. In crude analyses, lower educational level of parents was associated with an increased risk of childhood wheezing and asthma. After full adjustment, a lower educational level of mothers was associated with an increased risk of childhood asthma (junior high school (reference: high school); odds ratio (OR): 1.17, 95% CI, 1.01-1.36), and higher educational level, especially the mother's, was associated with an increased risk of childhood wheezing (technical junior college, technical/vocational college, or associate degree (ECD3); OR: 1.12, 95% CI, 1.06-1.18, bachelor's degree, or postgraduate degree; OR: 1.10, 95% CI, 1.03-1.18), and asthma (ECD3; OR: 1.13, 95% CI, 1.04-1.21). CONCLUSIONS: Parents' lower educational level was a crude risk factor for childhood wheezing and asthma. However, an increased risk of wheezing due to mothers' higher educational level was found after adjusting for pre-and post-natal factors.
  • Biomonitoring and temporal trends of bisphenols exposure in Japanese school children.
    Celine Gys; Yu Ait Bamai; Atsuko Araki; Michiel Bastiaensen; Noelia Caballero-Casero; Reiko Kishi; Adrian Covaci
    Environmental research, 191, 110172, 110172, Dec. 2020, [International Magazine]
    English, Scientific journal, The widely used chemical bisphenol A (BPA), applied in various consumer products, has been under scrutiny in the past 20 years due to its widespread detection in humans and potential detrimental effects on human health. Following the implementation of restrictions and phase-out initiatives, BPA has been replaced by other structurally similar bisphenols, which have not yet received the same level of research attention. In this study, we aimed to 1) investigated the internal exposure to seven bisphenols in morning void urine samples (n = 396) from 7-year-old children from Hokkaido, Japan and 2) assess possible time trends in the concentrations of bisphenols between 2012 and 2017. Information on demographic, indoor environment and dietary characteristics of participants were acquired through a self-administered questionnaire. All bisphenols were detected in the study population, with BPA, BPF and BPS showing detection frequencies >50%. Concentrations of bisphenols measured in the Japanese children in our study were generally lower compared to studies worldwide. We found that BPA concentrations decreased significantly over the study time period (average 6.5% per year), whereas BPS rose with 2.8% per year. Levels of BPA and BPF were higher in autumn compared to winter. Higher urinary BPF levels were significantly associated with higher concentrations of the oxidative stress biomarker, 8-hydroxy-2'-deoxyguanosine (8-OHdG). BPA and BPF levels were higher in children from families with lower household income. Bisphenol concentrations were significantly influenced by some other personal (e.g. household income), food intake (e.g. vegetables and cow milk) and indoor housing characteristics (e.g. flooring). This is the first study to report longitudinal time trends of bisphenols in Japan. The presented findings imply that further research on bisphenols is warranted in the future to monitor whether these time trends continue.
  • Between- and within-individual variability of urinary phthalate and alternative plasticizer metabolites in spot, morning void and 24-h pooled urine samples.
    Michiel Bastiaensen; Govindan Malarvannan; Celine Gys; Yu Ait Bamai; Atsuko Araki; Adrian Covaci
    Environmental research, 191, 110248, 110248, Dec. 2020, [International Magazine]
    English, Scientific journal, Due to international regulations, commonly used phthalates such as di(2-ethylhexyl) phthalate (DEHP) are being replaced by other phthalates, such as di-isononyl phthalate (DINP), and di-isodecyl phthalate (DIDP) and by alternative plasticizers (APs) with similar chemical characteristics, like di(isononyl)cyclohexane-1,2-dicarboxylate (DINCH), di(2-ethylhexyl) terephthalate (DEHTP), or di-(2-ethylhexyl) adipate (DEHA). Urinary concentrations of metabolites are frequently used in the exposure assessment of non-persistent chemicals and for biomonitoring purposes, the intra- and inter-day variability of the metabolites should be known. However, the short-term variability of AP and several phthalate biomarkers has not been investigated yet. In this study, we collected all spot samples from 10 healthy adults for 5 consecutive days and 24h pooled urine on one additional day to investigate the short-term variability of 22 biomarkers of phthalates and APs. Metabolites of DEP, DEHP, DiBP, DnBP, DBzP, DINP and DIDP were found in high detection frequencies, while metabolites of most APs were found in approximately 50% of the samples. The short-term reproducibility of metabolites with diet as primary source (DEHP, DINP, DIDP) was poor (intraclass correlation coefficient - ICC < 0.4), whereas biomarkers of DEP, DnBP, DiBP and BBzP showed good consistency, most likely due to more continuous sources resulting in less between-day variance. ICC values of AP metabolites were similar to those of DEHP, but more studies are required to confirm these findings. Overall, reproducibility improved considerably when values were corrected for urinary dilution and when only morning voids samples were considered. Levels in morning voids samples were consistent for 5 days and comparable to 24-h pooled urine for all metabolites except for OH-MEHTP, sum DINP and sum DIDP, which supports the use of morning voids in human biomonitoring studies.
  • Effect of prenatal exposure to per- and polyfluoroalkyl substances on childhood allergies and common infectious diseases in children up to age 7 years: The Hokkaido study on environment and children's health.
    Yu Ait Bamai; Houman Goudarzi; Atsuko Araki; Emiko Okada; Ikuko Kashino; Chihiro Miyashita; Reiko Kishi
    Environment international, 143, 105979, 105979, Oct. 2020, [International Magazine]
    English, Scientific journal, Per- and polyfluoroalkyl substances (PFAS) are widely used bio-accumulative chemicals in many industrial and household products. Experimental studies reported that exposure to PFAS results in immunotoxicity. We have previously reported that prenatal exposure to PFAS decreased the risk of allergies, while it increased the risk of infectious diseases at ages 2 and 4 years. However, it remains unclear whether the adverse effects of PFAS on allergies and infectious diseases continue until a reliable age of diagnosing allergies. This study aimed at investigating the effects of prenatal exposure to PFAS on the prevalence of allergies and infectious diseases in children up to age 7, from the Hokkaido Study. Among mother-child pairs enrolled in the Hokkaido study and followed up until the age of 7 years, 2689 participants with maternal PFAS, 1st trimester of pregnancy and 7-year-old questionnaire survey data were included in this study. Eleven PFAS in the 3rd-trimester plasma were measured using ultra-performance liquid chromatography coupled to triple quadrupole tandem mass spectrometry. Wheeze, rhino-conjunctivitis, and eczema were defined using the International Study of Asthma and Allergies on Childhood (ISAAC) questionnaire. History childhood infectious diseases diagnosed by a doctor was assessed by a mother-reported questionnaire at child's age 7. The relative risk of childhood allergies was calculated by generalized estimating equation models. The odds ratio of an episode of infectious diseases was calculated by logistic regression analysis, adjusted for potential confounders. The prevalence of various allergies and infectious diseases was: wheeze, 11.9%; rhino-conjunctivitis, 11.3%; eczema, 21.0%; chickenpox, 61.5%; otitis media, 55.7%; pneumonia, 30.6%; and respiratory syncytial virus infection, 16.8%. Prenatal exposure to perfluorooctanoic acid, perfluorodecanoic acid (PFDA), and perfluoroundecanoic acid (PFUnDA) was inversely associated with rhino-conjunctivitis, while that for perfluorooctanoate (PFOA), perfluorooctane sulfonate, PFUnDA, perfluorododecanoic acid (PFDoDA), and perfluorotridecanoic acid was inversely associated with eczema. For infectious diseases, PFDA and PFDoDA were associated with increased risk of pneumonia and PFOA was associated with increased risk of RSV infection among children not having any siblings (only-one-child). Our results corroborate the hypothesis on immunosuppressive and immunomodulating effects of PFAS on allergies and infectious diseases in children. These effects observed previously at 2 and 4 years continued until the age of 7 years. However, additional studies assessing inflammatory biomarkers along with ISAAC questionnaires, doctor-diagnosed allergies, and longer follow-ups are necessary to better assess the effects of exposure to chemicals on human immune outcomes.
  • Trajectories of the Psychological Status of Mothers of Infants With Nonsyndromic Orofacial Clefts: A Prospective Cohort Study From the Japan Environment and Children’s Study
    Yukihiro Sato; Eiji Yoshioka; Yasuaki Saijo; Toshinobu Miyamoto; Kazuo Sengoku; Hiroshi Azuma; Yusuke Tanahashi; Yoshiya Ito; Sumitaka Kobayashi; Machiko Minatoya; Yu Ait Bamai; Keiko Yamazaki; Sachiko Ito; Chihiro Miyashita; Atsuko Araki; Reiko Kishi
    The Cleft Palate-Craniofacial Journal, 58, 3, 105566562095139, 105566562095139, SAGE Publications, 26 Aug. 2020, [Peer-reviewed], [International Magazine]
    English, Scientific journal, Objective: This study examined psychological status trajectories of mothers of infants with nonsyndromic orofacial clefts in Japan.

    Design: Prospective cohort study.

    Setting: Data from the Japan Environment and Children’s Study.

    Participants: Infants with a nonsyndromic cleft (N = 148) including cleft lip and palate (CLP; n = 72), cleft lip (CL; n = 46), and cleft palate (CP; n = 30). The control group included unaffected infants (N = 84 454).

    Main Outcome Measures: At 15 weeks and 27 weeks of pregnancy and 12 months after birth, the Kessler Psychological Distress Scale (clinical cutoff ≥5) was used. At 1 month and 6 months after birth, the Edinburgh Postnatal Depression Scale (clinical cutoff ≥9) was used.

    Results: Prenatal diagnosis rates were unavailable. Mothers of infants with CLP had higher psychological distress than controls at 27 weeks of pregnancy (prevalence ratio [PR] = 1.36, 95% CI: 1.06-1.74) and postnatal depression at 1 month after birth (PR = 2.21, 95% CI: 1.53-3.19). Mothers of infants with CP showed heightened psychological distress at 27 weeks of pregnancy (PR = 1.62, 95% CI: 1.21-2.17) and postnatal depression 6 months after birth (PR = 1.86, 95% CI: 1.01-3.43). There was no significant association between CL and maternal psychological status. At 12 months after birth, no differences in distress were found between mothers of infants with a cleft and controls.

    Conclusions: Mothers of infants with orofacial clefts may need psychosocial support, particularly during pregnancy and the first year after birth.

  • Lifestyle behaviors and home and school environment in association with sick building syndrome among elementary school children: a cross-sectional study.
    Rahel Mesfin Ketema; Atsuko Araki; Yu Ait Bamai; Takeshi Saito; Reiko Kishi
    Environmental health and preventive medicine, 25, 1, 28, 28, 11 Jul. 2020, [International Magazine]
    English, Scientific journal, BACKGROUND: Sick building syndrome (SBS) refers to the combination of symptoms experienced by occupants of specific building characteristics. This study investigated the associations of children's lifestyle behaviors, allergies, home, and school environment with SBS symptoms. METHODS: A total of 4408 elementary school children living in Sapporo City, Japan participated in this study. SBS was determined on parental answers to MM080 standardized school questionnaires on symptoms that were weekly experienced by these children, and if the symptom is attributed to their home or school environment. The Japanese version of the International Study of Asthma and Allergies in Childhood questionnaire was used to assess wheeze, rhino-conjunctivitis, and eczema. A logistic regression analysis was conducted to evaluate the associations between SBS symptoms and variables by controlling the potential confounders (gender, grade, school, and parental history of allergies). A stepwise backward elimination was conducted to assess independent variables related to SBS. RESULTS: Participants revealed mucosal (6.9%), skin (2.0%), and general (0.8%) symptoms. The presence of one or more allergy was associated with increased mucosal and skin symptoms. Children who skipped breakfast, displayed faddiness (like/dislike of food), had constipation, have insufficient sleep, did not feel refreshed after sleep, and lacked deep sleep showed significantly high odds ratios with SBS symptoms. The stepwise analysis showed faddiness for mucosal symptoms and not feeling refreshed after sleep for mucosal and skin symptoms, whereas constipation and lacking deep sleep for general symptoms were independent variables in increasing the symptoms. We found no significant relationship between SBS in children and schools. Considering children's home, old building, no ventilation, wall-to-wall carpet, and heavy nearby traffic were associated with elevated mucosal symptom, while living in a multifamily home increased general symptoms. Home dampness was an independent variable in increasing all SBS symptoms. CONCLUSIONS: Allergies and lifestyle behaviors were associated with increased SBS in children, including skipping breakfast, displaying faddiness, constipation, insufficient sleep, not feeling refreshed after sleep, and the lack of deep sleep. Further, dampness at home was associated with increase in all SBS symptoms. Lifestyle (e.g., eating and sleeping habits) and home (i.e., dampness) improvements might alleviate SBS symptoms in children.
  • Temporal trends and determinants of PFR exposure in the Hokkaido Study.
    Michiel Bastiaensen; Yu Ait Bamai; Atsuko Araki; Houman Goudarzi; Satoshi Konno; Sachiko Ito; Chihiro Miyashita; Yiming Yao; Reiko Kishi; Adrian Covaci
    International journal of hygiene and environmental health, 228, 113523, 113523, Jul. 2020, [Peer-reviewed], [International Magazine]
    English, Scientific journal, The phase-out of polybrominated diphenyl ethers (PBDE) flame retardants has led to the rapid increase of alternatives such as phosphate flame retardants and plasticizers (PFRs) in many consumer products. Exposure to these additive chemicals is widespread and potentially harmful to humans and the environment. In the present study, we assessed the exposure to PFRs through the analysis of metabolites in urine collected from 7-year old children from Hokkaido, Japan between 2012 and 2017. This allowed us to investigate temporal and seasonal trends for PFR metabolite concentrations and to study determinants of exposure. Thirteen metabolites of seven PFRs were measured in morning spot urine samples (n = 400). Multiple regression models were used to quantify the yearly increase in metabolite concentrations per sampling year. Information on the demographics, indoor environment and dietary habits of the participants were derived from self-administered questionnaires. PFR metabolite concentrations were comparable to our previous study of school children (7-12 years old). Eight PFR metabolites were detected in >50% of the samples. During the study time period, concentrations of three metabolites increased significantly: bis(1,3-dichloro-2-propyl) phosphate (BDCIPP; 13.3% per year), 1-hydroxy-2-propyl bis(1-chloro-2-propyl) phosphate (BCIPHIPP; 12.9% per year), and 2-ethylhexyl phenyl phosphate (EHPHP; 6.7% per year). We also found seasonality as a determinant for several PFR metabolites, with 2-fold higher levels in summer for BCIPHIPP and BDCIPP. Concentrations were also significantly impacted by ventilation habits. More frequent window opening or use of mechanical ventilation was consistently associated with higher levels of PFR metabolites in children's urine. This is the first study to show that human exposure to PFRs has increased in recent years in Japan, which indicates that further research into this class of chemicals is warranted.
  • Population attributable fractions of modifiable risk factors for nonsyndromic orofacial clefts: a prospective cohort study from the Japan Environment and Children’s Study
    Yukihiro Sato; Eiji Yoshioka; Yasuaki Saijo; Toshinobu Miyamoto; Kazuo Sengoku; Hiroshi Azuma; Yusuke Tanahashi; Yoshiya Ito; Sumitaka Kobayashi; Machiko Minatoya; Yu Ait Bamai; Keiko Yamazaki; Sachiko Itoh; Chihiro Miyashita; Atsuko Araki; Reiko Kishi; Japan Environment and Children’s Study (JECS) Group
    Journal of Epidemiology, 31, 4, 272, 279, Apr. 2020, [Peer-reviewed], [Domestic magazines]
    English, Scientific journal, BACKGROUND: Population impact of modifiable risk factors on orofacial clefts is still unknown. This study aimed to estimate population attributable fractions (PAFs) of modifiable risk factors for nonsyndromic cleft lip with or without cleft palate (CL±P) and cleft palate only (CP) in Japan. METHODS: We conducted a prospective cohort study using data from the Japan Environment and Children's Study, which recruited pregnant women from 2011 to 2014. We estimated the PAFs of maternal alcohol consumption, psychological distress, maternal active and passive smoking, abnormal body mass index (BMI) (<18.5 and ≥25 kg/m2), and non-use of a folic acid supplement during pregnancy for nonsyndromic CL±P and CP in babies. RESULTS: A total of 94,174 pairs of pregnant women and their single babies were included. Among them, there were 146 nonsyndromic CL±P cases and 41 nonsyndromic CP cases. The combined adjusted PAF for CL±P of the modifiable risk factors excluding maternal alcohol consumption was 34.3%. Only maternal alcohol consumption was not associated with CL±P risk. The adjusted PAFs for CL±P of psychological distress, maternal active and passive smoking, abnormal BMI, and non-use of a folic acid supplement were 1.4% (95% confidence interval [CI], -10.7 to 15.1%), 9.9% (95% CI, -7.0 to 26.9%), 10.8% (95% CI, -9.9 to 30.3%), 2.4% (95% CI, -7.5 to 14.0%), and 15.1% (95% CI, -17.8 to 41.0%), respectively. We could not obtain PAFs for CP due to the small sample size. CONCLUSIONS: We reported the population impact of the modifiable risk factors on CL±P, but not CP. This study might be useful in planning the primary prevention of CL±P.
  • Combined exposure to phthalate esters and phosphate flame retardants and plasticizers and their associations with wheeze and allergy symptoms among school children.
    Atsuko Araki; Yu Ait Bamai; Michiel Bastiaensen; Nele Van den Eede; Toshio Kawai; Tazuru Tsuboi; Chihiro Miyashita; Sachiko Itoh; Houman Goudarzi; Satoshi Konno; Adrian Covaci; Reiko Kishi
    Environmental research, 183, 109212, 109212, 03 Feb. 2020, [Peer-reviewed], [International Magazine]
    English, Scientific journal, BACKGROUND: Phthalate esters and phosphate flame retardants and plasticizers (PFRs) are both used as plasticizers and are commonly detected in indoor environments. Although both phthalates and PFRs are known to be associated with children's wheeze and allergic symptoms, there have been no previous studies examining the effects of mixtures of these exposures. OBJECTIVES: To investigate the association between exposure to mixtures of phthalate esters and PFRs, and wheeze and allergic symptoms among school-aged children. METHODS: A total of 128 elementary school-aged children were enrolled. Metabolites of 3 phthalate esters and 7 PFRs were measured in urine samples. Parent-reported symptoms of wheeze, rhinoconjunctivitis, and eczema were evaluated using the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire. In the primary model, we created a phthalate ester and PFR mixture exposure index, and estimated odds ratios (ORs) using weighted quantile sum (WQS) regression and quantile g (qg)-computation. The two highest chemicals according to qg-computation weight %s were combined to create a combination high × high exposure estimate, with ORs calculated using the "low × low" exposure group as the reference category. Concentrations of each metabolite were corrected by multiplying this value by the sex- and body size-Standardised creatinine concentration and dividing by the observed creatinine value. All models were adjusted for sex, grade, dampness index and annual house income. RESULTS: The odds ratio of rhinoconjunctivitis for the association between exposure to chemical mixtures according to the WQS index positive models was; OR = 2.60 (95% confidence interval [CI]: 1.38-5.14). However, wheeze and eczema of the WQS index positive model, none of the WQS index negative models or qg-computation result yielded statistically significant results. Combined exposure to the two highest WQS weight %s of "high-high" ΣTCIPP and ΣTPHP was associated with an increased prevalence of rhino-conjunctivitis, OR = 5.78 (1.81-18.43) to the "low × low" group. CONCLUSIONS: Significant associations of mixed exposures to phthalates and PFRs and increased prevalence of rhinoconjunctivitis was found among elementary school-aged children in the WQS positive model. Mixed exposures were not associated with any of allergic symptoms in the WQS negative model or qg-computation approach. However, the combined effects of exposure to two PFRs suggested an additive and/or multiplicative interaction, potentially increasing the prevalence of rhinoconjunctivitis. A further study with a larger sample size is needed to confirm these results.
  • Early-Life Environmental Influences on Allergic Diseases
    Ait Bamai, Y.; Miyashita, C.; Araki, A.; Kishi, R.
    Early-life Environmental Exposure and Disease: Facts and Perspectives, 2020
    Scientific journal
  • Cat and Dog Ownership in Early Life and Infant Development: A Prospective Birth Cohort Study of Japan Environment and Children's Study.
    Machiko Minatoya; Atsuko Araki; Chihiro Miyashita; Sachiko Itoh; Sumitaka Kobayashi; Keiko Yamazaki; Yu Ait Bamai; Yasuaki Saijyo; Yoshiya Ito; Reiko Kishi; The Japan Environment And Children's Study Group
    International journal of environmental research and public health, 17, 1, 27 Dec. 2019, [Peer-reviewed], [International Magazine]
    English, Scientific journal, Contact with companion animals has been suggested to have important roles in enhancing child development. However, studies focused on child development and pet ownership at a very early age are limited. The purpose of the current study was to investigate child development in relation to pet ownership at an early age in a nationwide prospective birth cohort study: the Japan Environment and Children's Study. Associations between cat and dog ownership at six months and infant development at 12 months of age were examined in this study. Infant development was assessed using the Ages & Stages QuestionnairesTM (ASQ-3) at 12 months. Among participants of (Japan Environment and Children's Study) JECS, those with available data of cat and dog ownership at six months and data for the ASQ-3 at 12 months were included (n = 78,868). Having dogs showed higher percentages of pass in all five domains measured by ASQ-3 (communication, gross motor, fine motor, problem-solving, and personal-social) compared to those who did not have dogs. Significantly decreased odds ratios (ORs) of developmental delays were observed in association with having dogs in all fix domains (communication: OR = 0.73, gross motor: OR = 0.86, fine motor: OR = 0.84, problem-solving: OR = 0.90, personal-social: OR = 0.83). This study suggested that early life dog ownership may reduce the risks of child developmental delays.
  • Multiple exposures to organophosphate flame retardants alter urinary oxidative stress biomarkers among children: The Hokkaido Study.
    Yu Ait Bamai; Michiel Bastiaensen; Atsuko Araki; Houman Goudarzi; Satoshi Konno; Sachiko Ito; Chihiro Miyashita; Yiming Yao; Adrian Covaci; Reiko Kishi
    Environment international, 131, 105003, 105003, Oct. 2019, [Peer-reviewed], [International Magazine]
    English, Scientific journal, Organophosphate flame retardants (PFRs) are used as additives in plastics and other applications such as curtains and carpets as a replacement for brominated flame retardants. As such, exposure to PFR mixtures is widespread, with children being more vulnerable than adults to associated health risks such as allergies and inflammation. Oxidative stress is thought to be able to modulate the development of childhood airway inflammation and atopic dermatitis. To evaluate these associations, the present study investigated the relationship between urinary PFR metabolites, their mixtures and urinary oxidative stress biomarkers in children as part of the Hokkaido Study on Environment and Children's Health. The levels of the oxidative stress biomarkers, such as 8-hydroxy-2'-deoxyguanosine (8-OHdG), hexanoyl-lysine (HEL), and 4-hydroxynonenal (HNE), and of 14 PFR metabolites were measured in morning spot urine samples of 7-year-old children (n = 400). Associations between PFR metabolites or PFR metabolite mixtures and oxidative stress biomarkers were examined by multiple regression analysis and weighted quantile sum regression analysis, respectively. We found that the non-chlorinated PFR metabolites, 2-ethylhexyl phenyl phosphate (EHPHP), bis(2-butoxyethyl) phosphate (BBOEP), and diphenyl phosphate (DPHP) were associated with increased levels of oxidative stress biomarkers. Furthermore, the PFR metabolite mixture was associated with increased levels of HEL and HNE, but not 8-OHdG. The combination of elevated top 2 PFR metabolites was not associated with higher urinary oxidative stress marker levels. This is the first study to report associations between urinary PFR metabolites and oxidative stress biomarkers among children.
  • Association between perfluoroalkyl substance exposure and thyroid hormone/thyroid antibody levels in maternal and cord blood: The Hokkaido Study.
    Itoh S; Araki A; Miyashita C; Yamazaki K; Goudarzi H; Minatoya M; Ait Bamai Y; Kobayashi S; Okada E; Kashino I; Yuasa M; Baba T; Kishi R
    Environment international, 133, Pt A, 105139, 105139, Sep. 2019, [Peer-reviewed], [International Magazine]
    English, Scientific journal, BACKGROUND: Thyroid antibodies (TAs) are the most common cause of hypothyroidism during gestation. Although previous studies found that prenatal exposure to perfluoroalkyl substances (PFASs) disrupts thyroid hormones (THs) in humans, their effects on TAs during the perinatal period have not been investigated. OBJECTIVE: To explore the associations between prenatal exposure to eleven different PFASs from two different groups (carboxylates and sulfonates) and the expression of THs and TAs in maternal and cord blood while considering maternal TA status. METHODS: In a prospective birth cohort (the Hokkaido Study), we included 701 mother‑neonate pairs recruited in 2002-2005 for whom both prenatal maternal and cord blood samples were available. Eleven PFASs were measured in maternal plasma obtained at 28-32 weeks of gestation using ultra-performance liquid chromatography coupled with triple quadrupole tandem mass spectrometry. THs and TAs including thyroid stimulating hormone (TSH), free triiodothyronine (FT3), free thyroxine (FT4), thyroid peroxidase antibody (TPOAb), and thyroglobulin antibody (TgAb) were measured in maternal blood during early pregnancy (median 11 gestational weeks), and in cord blood at birth. RESULTS: The median levels of TgAb and TPOAb in maternal serum were 15.0 and 6.0 IU/mL, respectively. The median TgAb level in neonates was 38.0 IU/mL, and TPOAb were detected in only 12.3% of samples. Maternal FT3 level was positively associated with PFAS levels in both TA-positive and TA-negative mothers. Maternal perfluorooctanoate was inversely associated with maternal TPOAb. Among boys, some maternal PFASs were associated with higher TSH and lower FT3 levels in maternal TA-negative group, while perfluorodecanoic acid was associated with lower TSH in maternal TA-positive group. Among girls, some PFAS of mothers showed associations with lower TSH and higher FT3 in maternal TA-negative group, while perfluorododecanoic acid was associated with lower FT4 in maternal TA-positive. Maternal PFASs showed associations with boy's TgAb inversely in maternal TA-negative group and with girl's TgAb positively in maternal TA-positive group. CONCLUSIONS: Our results suggest thyroid disrupting effects of PFAS exposure and susceptibility vary depending on maternal TA levels.
  • Biomonitoring of organophosphate flame retardants and plasticizers in children: Associations with house dust and housing characteristics in Japan.
    Michiel Bastiaensen; Yu Ait Bamai; Atsuko Araki; Nele Van den Eede; Toshio Kawai; Tazuru Tsuboi; Reiko Kishi; Adrian Covaci
    Environmental research, 172, 543, 551, May 2019, [Peer-reviewed], [International Magazine]
    English, Scientific journal, Indoor environments contain a wide range of new chemicals such as phosphate flame retardants and plasticizers (PFRs). Despite recent epidemiological evidence suggesting that children might be affected by widespread exposure to PFRs, questions remain about the various exposure pathways to these chemicals. Therefore, the aim of this study was to investigate exposure to PFRs by measuring the concentrations a set of urinary metabolites for schoolchildren from Japan (n = 128) and associating them with house dust concentrations and housing characteristics. Detectable concentrations of both diaryl and dialkyl phosphates (DAPs) and hydroxylated metabolites (HO-PFRs) were found in urine samples of almost all children. 2-Hydroxyethyl bis(2-butoxyethyl) phosphate (BBOEHEP) was the most frequently detected metabolite (98%) followed by 1-hydroxy-2-propyl bis(1-chloro-2-propyl) phosphate (BCIPHIPP, 95%) and tris(chloroethyl) phosphate (TCEP). Next to BBOEHEP, two other metabolites of tris(2-butoxyethyl) phosphate (TBOEP) were also frequently detected. Significant correlations of moderate strength were found between parent compounds detected in high concentrations in house dust (TBOEP, tris(2-chloroisopropyl) phosphate (TCIPP)) and their corresponding metabolites, suggesting that dust is a primary exposure source for these PFRs. Several personal and housing characteristics, such as gender, income, and the use of PVC and ventilation were associated with metabolite concentrations in multivariate linear regression. Overall, this study showed that Japanese schoolchildren are exposed to a wide range of PFRs.
  • Dose-dependent associations between prenatal caffeine consumption and small for gestational age, preterm birth, and reduced birthweight in the Japan Environment and Children's Study.
    Sumitaka Kobayashi; Fumihiro Sata; Katsuyuki Murata; Yasuaki Saijo; Atsuko Araki; Chihiro Miyashita; Sachiko Itoh; Machiko Minatoya; Keiko Yamazaki; Yu Ait Bamai; Reiko Kishi
    Paediatric and perinatal epidemiology, 33, 3, 185, 194, May 2019, [Peer-reviewed], [International Magazine]
    English, Scientific journal, BACKGROUND: Few previous studies have investigated the association between prenatal caffeine intake and birth size (small for gestational age [SGA], preterm birth, and birthweight Z-score) in Japan. OBJECTIVES: We examined the dose-dependency of this association (prenatal caffeine consumption and birth size) as part of the Japan Environment and Children's Study. METHODS: A prospective birth cohort included 94 876 fetuses in Japan. Participants were enrolled between January 2011 and March 2014. Adjusted multiple linear regression and Cox regression models were used to examine the association between prenatal caffeine levels and infant birth size. RESULTS: The median estimated caffeine consumption during pregnancy was 125.5 mg/day, as determined by self-administered questionnaires. There were 7252 SGA infants (7.6%) and 4281 preterm birth infants (4.5%). Compared with infants of mothers whose caffeine consumption during pregnancy was in the lowest quartile (4.2 to <86.4 mg/day), infants of mothers whose caffeine consumption was in the highest quartile 4 (205.5-5080.0 mg/day) were at an increased risk of SGA (relative risk [RR] 1.18, 95% confidence interval [CI] 1.10, 1.27), and at an increased risk of preterm birth at the second trimester of gestation (RR 1.94, 95% CI 1.12, 3.37), with a 0.32-day reduction in gestational age (95% CI -0.52, -0.12) and with a 0.07 reduction in birthweight Z-score observed (95% CI -0.09, -0.05). CONCLUSIONS: Prenatal caffeine consumption was associated with birth size. However, as the association between prenatal caffeine consumption and birth size was likely confounded by unpredicted potential factors, our confidence in the true causality of the association is moderate.
  • Association of blood mercury levels during pregnancy with infant birth size by blood selenium levels in the Japan Environment and Children's Study: A prospective birth cohort.
    Sumitaka Kobayashi; Reiko Kishi; Yasuaki Saijo; Yoshiya Ito; Koji Oba; Atsuko Araki; Chihiro Miyashita; Sachiko Itoh; Machiko Minatoya; Keiko Yamazaki; Yu Ait Bamai; Tosiya Sato; Shin Yamazaki; Shoji F Nakayama; Tomohiko Isobe; Hiroshi Nitta
    Environment international, 125, 418, 429, Apr. 2019, [Peer-reviewed], [International Magazine]
    English, Scientific journal, BACKGROUND: It is necessary to determine whether there are adverse health effects of prenatal exposure to long-term, low levels of mercury and selenium. However, there are limited that reports on the association between mercury levels by selenium levels and birth size. Therefore, we examined whether maternal mercury levels during pregnancy had any effect on infant birth size, and size, and whether selenium levels influenced this relationship. OBJECTIVES: To examine the association between mercury and selenium levels during pregnancy with infant birth size. METHODS: The Japan Environment and Children's Study is a prospective birth cohort conducted between 2011 and 2014. Total mercury levels and total selenium levels in maternal blood during the second and third trimesters were measured using Inductively Coupled Plasma-Mass Spectrometry. Birth weight and small-for-gestational-age were confirmed by medical records. Small-for-gestational-age was defined as birth weight below the 10th percentile according to standard percentile for gender, parity, and gestational age. Multiple linear and logistic regression analyses were used to examine the association between maternal mercury exposure and birth weight or small-for-gestational-age adjusted for confounders (including maternal age and body mass index pregnancy). RESULTS: Overall, 15,444 pregnant women were included in this study. Median (inter-quartile range) of blood mercury and selenium levels were 3.66 (2.59-5.18) ng/g and 170.0 (158.0-183.0) ng/g, respectively. Compared to infants of mothers with the highest blood selenium level, those of mothers with the lowest blood selenium level had neither a significant birth weight increase (9 g, 95% confidence interval: -6, 25) nor a significant odds ratio for small-for-gestational-age (0.903, 95% confidence interval: 0.748, 1.089). Compared to infants of mothers with the lowest blood mercury level, those of mothers with the highest blood mercury level had neither a significant birth weight reduction (-12 g, 95% confidence interval: -27, 4) nor a significant odds ratio for small-for-gestational-age (0.951, 95% confidence interval: 0.786, 1.150). Compared to infants of mothers with the lowest quartile of maternal blood mercury level, all infants of mothers with the highest quartile of maternal blood mercury level had a reduced birth head circumference of 0.073 cm (95% confidence interval: -0.134, -0.011). CONCLUSIONS: There was no association between maternal blood mercury levels and small-for-gestational-age and birth weight among 15,444 pregnant women. In a Japanese population, which has a relatively higher blood mercury level than reported in Western population, reduced birth size was not found to be associated with blood mercury levels, with the exception of birth head circumference.
  • Associations Between Metal Levels in Whole Blood and IgE Concentrations in Pregnant Women Based on Data From the Japan Environment and Children's Study.
    Tsuji M; Koriyama C; Ishihara Y; Yamamoto M; Yamamoto-Hanada K; Kanatani K; Bamai YA; Onishi K; Senju A; Araki S; Shibata E; Morokuma S; Sanefuji M; Kitazawa H; Saito M; Umezawa M; Onoda A; Kusuhara K; Tanaka R; Kawamoto T; Japan Environment; Children’s Study Group
    Journal of epidemiology, 29, 12, 478, 486, Jan. 2019, [Peer-reviewed], [Domestic magazines]
    English, Scientific journal, BACKGROUND: Metal exposures could possibly affect allergic responses in pregnant women, although no studies have yet shown a clear relationship between the two, and such exposures might also affect the development of allergic diseases in children. METHODS: We investigated the relationship between metal concentrations in whole blood and immunoglobulin E (IgE; total and specific) in 14,408 pregnant women who participated in the Japan Environment and Children's Study. The subjects submitted self-administered questionnaires, and blood samples were collected from them twice, specifically, during the first trimester and again during the second/third trimester. Concentrations of the metals Cd, Pb, Hg, Se, and Mn, as well as serum total and allergen-specific IgEs for egg white, house dust-mites (HDM), Japanese cedar pollen (JCP), animal dander, and moth, were measured. Allergen-specific IgE(s) were divided based on concentrations <0.35 or ≥0.35 UA/mL, and the metal levels were divided into quartiles. RESULTS: Multivariable logistic regression analysis showed that there was a significant negative correlation between HDM- and animal dander-specific IgEs and Hg and Mn concentrations. Conversely, there was a significant positive relationship between JCP-specific IgE and Hg and Se concentrations. CONCLUSIONS: Metal exposures may be related to both increases and decreases in allergen-specific IgEs in pregnant women.
  • Association of filaggrin gene mutations and childhood eczema and wheeze with phthalates and phosphorus flame retardants in house dust: The Hokkaido study on Environment and Children's Health.
    Yu Ait Bamai; Atsuko Araki; Toshifumi Nomura; Toshio Kawai; Tazuru Tsuboi; Sumitaka Kobayashi; Chihiro Miyashita; Masae Takeda; Hiroshi Shimizu; Reiko Kishi
    Environment international, 121, Pt 1, 102, 110, Dec. 2018, [Peer-reviewed], [International Magazine]
    English, Scientific journal, BACKGROUND AND AIM: Exposure to phthalates and phosphorus flame retardants (PFRs) is considered to be a risk factor for asthma and allergies. However, little is known about the contribution of loss-of-function mutations in the gene encoding filaggrin (FLG) gene, which are considered to be predisposing factors for eczema and asthma, to these associations. We investigated the associations between exposure to phthalates and PFRs in dust and eczema/wheeze among Japanese children, taking into consideration loss-of-function mutations in FLG. METHODS: This study was part of the Hokkaido study on Environment and Children's Health. Seven phthalates and 11 PFRs in household dust were measured by gas chromatography-mass spectrometry. Eczema and wheeze were assessed in children aged 7 years using the International Study of Asthma and Allergies in Childhood questionnaire. Eight FLG mutations previously identified in the Japanese population were extracted from cord blood samples. Children with one or more FLG mutations were considered to be positive for FLG mutations. The study included 296 children who had complete data (birth records, FLG mutations, first trimester and 7 years questionnaires, and phthalate/PFR levels). Odds ratios (ORs) and 95% confidential intervals (CIs) of eczema and wheeze were calculated for log-transformed phthalate/PFR levels by logistic regression. We also performed stratified analyses based on FLG mutations. RESULTS: The prevalence rates of eczema and wheeze were 20.6% and 13.9%, respectively. Among children without any FLG mutations, tris (1, 3-dichloro-2-propyl) phosphate (TDCIPP) increased the OR of wheeze, (OR: 1.22, CI: 1.00-1.48). Significant p values for trends were found between tris (2-butoxyethyl) phosphate (TBOEP) and eczema and di-iso-nonyl phthalate (DiNP) and eczema among children without any FLG mutations, respectively. CONCLUSIONS: Despite our limited sample size and cross-sectional study design, the effects of indoor environmental factors on childhood eczema and wheeze were clearer in children without loss-of-function mutations in FLG than in children with mutations. Children with FLG mutations might already be cared for differently in terms of medication or parental lifestyle. Further studies in larger populations are warranted so that severity of symptoms and combinations of FLG mutations can be investigated.
  • Contrasting associations of maternal smoking and pre-pregnancy BMI with wheeze and eczema in children
    Houman Goudarzi; Satoshi Konno; Hirokazu Kimura; Atsuko Araki; Chihiro Miyashita; Sachiko Itoh; Yu Ait Bamai; Hiroki Kimura; Kaoruko Shimizu; Masaru Suzuki; Yoichi M. Ito; Masaharu Nishimura; Reiko Kishi
    Science of the Total Environment, 639, 1601, 1609, Elsevier B.V., 15 Oct. 2018, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • Associations between allergic symptoms and phosphate flame retardants in dust and their urinary metabolites among school children.
    Araki A; Bastiaensen M; Ait Bamai Y; Van den Eede N; Kawai T; Tsuboi T; Ketema RM; Covaci A; Kishi R
    Environment international, 119, 438, 446, Oct. 2018, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • Determinants and Temporal Trends of Perfluoroalkyl Substances in Pregnant Women: The Hokkaido Study on Environment and Children's Health.
    Meng-Shan Tsai; Chihiro Miyashita; Atsuko Araki; Sachiko Itoh; Yu Ait Bamai; Houman Goudarzi; Emiko Okada; Ikuko Kashino; Hideyuki Matsuura; Reiko Kishi
    International journal of environmental research and public health, 15, 5, 14 May 2018, [Peer-reviewed], [International Magazine]
    English, Scientific journal, Perfluoroalkyl substances (PFAS) are persistent bio-accumulative chemicals that impact the health of pregnant women and their children. PFAS derive from environmental and consumer products, which depend on human lifestyle, socioeconomic characteristics, and time variation. Here, we aimed to explore the temporal trends of PFAS in pregnant women and the characteristics related to maternal PFAS concentration. Our study is part of the Hokkaido Study on Environment and Children's Health, the Hokkaido large-scale cohort that recruited pregnant women between 2003 and 2011. Blood samples were acquired from pregnant women during the third trimester to measure PFAS and cotinine concentrations. Maternal basic information was collected with a baseline structured questionnaire. Eleven PFAS were measured from 2123 samples with ultra-performance liquid chromatography coupled with triple quadrupole tandem mass spectrometry. Eight PFAS were above 80% detection rate and were included in the final analysis. We used multivariable linear regression to analyze the association of pregnant women characteristics with the levels of eight PFAS. The temporal trend of PFAS was observed in two periods (August 2003 to January 2006 and February 2006 to July 2012). The concentration of perfluorooctane sulfonate (PFOS) significantly decreased from August 2003 to January 2006 and from February 2006 to July 2012. The concentrations of perfluorododecanoic acid (PFDoDA), perfluoroundecanoic acid (PFUnDA), and perfluorotridecanoic acid (PFTrDA) increased significantly between August 2003 and January 2006, whereas they decreased significantly between February 2006 and July 2012. Women with pre-pregnancy body mass index (BMI) >25 kg/m² had lower PFUnDA, PFDoDA, and PFTrDA levels than did those with normal BMI (18.5⁻24.9 kg/m²). Pregnant women, who were active smokers (cotinine > 11.49 ng/mL), had higher PFOS than the non-smokers (cotinine < 0.22 ng/mL). Lower levels of PFHxS, PFOS, PFOA, PFNA, and PFDA were observed in women, who had given birth to more than one child. There were also significant positive associations between PFAS levels and annual income or maternal education. PFAS levels varied in women with higher pre-pregnancy BMI, active smoking status, higher education level and annual income. The causes of the individual PFAS differences should be explored in an independent study.
  • 【住環境における健康リスク要因とそのマネジメント】科学的エビデンスに基づく『新シックハウス症候群に関する相談と対策マニュアル(改訂新版)』を作成して
    岸 玲子; 吉野 博; 荒木 敦子; 西條 泰明; 東 賢一; 河合 俊夫; 大和 浩; 大澤 元毅; 柴田 英治; 田中 正敏; 増地 あゆみ; 湊屋 街子; アイツバマイ ゆふ
    日本衛生学雑誌, 73, 2, 116, 129, (一社)日本衛生学会, May 2018
    Japanese, 科学的エビデンスに基づく「新シックハウス症候群に関する相談と対策マニュアル(改訂新版)」を作成したので紹介した。このマニュアルでは、近年震災や豪雨等の災害に伴って入居者が増えている仮設住宅の問題や、地球温暖化による熱中症と室内環境などの最近の問題、電磁過敏症に関する系統的レビューについて記載した。また、快適で健康な建物を実現する上で必要な基礎的な理論、設計の考え方と方法、建物の使い方、設備の調整の方法や扱い方についても解説した。
  • 【住環境における健康リスク要因とそのマネジメント】 科学的エビデンスに基づく『新シックハウス症候群に関する相談と対策マニュアル(改訂新版)』を作成して
    岸 玲子; 吉野 博; 荒木 敦子; 西條 泰明; 東 賢一; 河合 俊夫; 大和 浩; 大澤 元毅; 柴田 英治; 田中 正敏; 増地 あゆみ; 湊屋 街子; アイツバマイ ゆふ
    日本衛生学雑誌, 73, 2, 116, 129, (一社)日本衛生学会, May 2018
    Japanese, 科学的エビデンスに基づく「新シックハウス症候群に関する相談と対策マニュアル(改訂新版)」を作成したので紹介した。このマニュアルでは、近年震災や豪雨等の災害に伴って入居者が増えている仮設住宅の問題や、地球温暖化による熱中症と室内環境などの最近の問題、電磁過敏症に関する系統的レビューについて記載した。また、快適で健康な建物を実現する上で必要な基礎的な理論、設計の考え方と方法、建物の使い方、設備の調整の方法や扱い方についても解説した。
  • Indoor environmental pollutants and their association with sick house syndrome among adults and children in elementary school
    Reiko Kishi; Rahel Mesfin Ketema; Yu Ait Bamai; Atsuko Araki; Toshio Kawai; Tazuru Tsuboi; Ikue Saito; Eiji Yoshioka; Takeshi Saito
    Building and Environment, 136, 293, 301, May 2018, [Peer-reviewed]
    English, Scientific journal
  • Effects of prenatal di(2-ethylhexyl) phthalate exposure on childhood allergies and infectious diseases: The Hokkaido Study on Environment and Children's Health
    Yu Ait Bamai; Chihiro Miyashita; Atsuko Araki; Tamie Nakajima; Seiko Sasaki; Reiko Kishi
    Science of the Total Environment, 618, 1408, 1415, Elsevier B.V., 15 Mar. 2018, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • Association between prenatal bisphenol A and phthalate exposures and fetal metabolic related biomarkers: The Hokkaido study on Environment and Children's Health.
    Machiko Minatoya; Atsuko Araki; Chihiro Miyashita; Yu Ait Bamai; Sachiko Itoh; Jun Yamamoto; Yu Onoda; Kazuki Ogasawara; Toru Matsumura; Reiko Kishi
    Environmental research, 161, 505, 511, Feb. 2018, [Peer-reviewed], [International Magazine]
    English, Scientific journal, Bisphenol A and phthalates are widely detected in human urine, blood, breast milk, and amniotic fluid. Both bisphenol A and phthalates have been suggested as playing a role in obesity epidemics. Exposure to these chemicals during fetal development, and its consequences should be concerning because they can cross the placenta. Thus, this study aimed to assess the association between prenatal exposure to bisphenol A and phthalates, and cord blood metabolic-related biomarkers. Maternal serum was used during the first trimester, to determine prenatal exposure to bisphenol A and phthalates. Levels of metabolic-related biomarkers in the cord blood were also determined. Linear regression models were applied to the 365 participants with both, exposure and biomarker assessments, adjusted for maternal age, pre-pregnancy body mass index, parity, education, and sex of the child. The level of bisphenol A was negatively associated with the leptin level (β = -0.06, 95% confidence interval [CI]: -0.11, -0.01), but was positively associated with the high-molecular-weight adiponectin level, with marginal significance (β = 0.03, 95%CI: 0.00, 0.06). The mono-isobutyl phthalate (MiBP), mono-n-butyl phthalate (MnBP), mono-(2-ethylhexyl) phthalate (MEHP), and summation of MEHP and MECPP to represent DEHP exposure (∑DEHPm) levels were inversely associated with the leptin levels (β=-0.14, 95%CI: -0.27, -0.01; β = -0.12, 95%CI: -0.24, 0.00 with marginal significance; β=0.08, 95%CI: -0.14, -0.03; and β = -0.09, 95%CI: -0.16, -0.03, respectively). The present study provided some evidence that prenatal exposure to bisphenol A and certain phthalates may modify fetal adiponectin and leptin levels.
  • Prevalence and risk of birth defects observed in a prospective cohort study: The Hokkaido study on environment and children’s health
    Hanaoka, T.; Tamura, N.; Ito, K.; Sasaki, S.; Araki, A.; Ikeno, T.; Miyashita, C.; Ito, S.; Minakami, H.; Cho, K.; Endo, T.; Baba, T.; Miyamoto, T.; Sengoku, K.; Kishi, R.; Goudarzi, H.; Minatoya, M.; Kobayashi, S.; Yamazaki, K.; Nishihara, S.; Bamai, Y.A.; Miura, R.; Kobayashi, S.; Uno, A.; Katoh, S.; Baba, T.; Yila, T.; Braimoh, T.; Kashino, I.; Nakajima, S.; Baba, T.; Saijyo, Y.; Yoshioka, E.; Miyamoto, T.; Okuyama, K.; Sata, F.; Kita, T.
    Journal of Epidemiology, 28, 3, 2018
    Scientific journal
  • Prenatal exposure to dioxin-like compounds is associated with decreased cord blood IgE and increased risk of wheezing in children aged up to 7 years: The Hokkaido study
    Chihiro Miyashita; Yu Ait Bamai; Atsuko Araki; Sachiko Itoh; Machiko Minatoya; Asumitaka Kobayashi; Jumboku Kajiwara; Tsuguhide Hori; Reiko Kishi
    SCIENCE OF THE TOTAL ENVIRONMENT, 610, 191, 199, Jan. 2018, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • [New Scientific Evidence-based Public Health Guidelines and Practical Manual for Prevention of Sick House Syndrome].
    Reiko Kishi; Hiroshi Yoshino; Atsuko Araki; Yasuaki Saijo; Kenichi Azuma; Toshio Kawai; Hiroshi Yamato; Haruki Osawa; Eiji Shibata; Masatoshi Tanaka; Ayumi Masuchi; Machiko Minatoya; Yu Ait Bamai
    Nihon eiseigaku zasshi. Japanese journal of hygiene, 73, 2, 116, 129, 2018, [Peer-reviewed], [Domestic magazines]
    Japanese, Scientific journal, Recently, we have published a book containing evidence-based public health guidelines and a practical manual for the prevention of sick house syndrome. The manual is available through the homepage of the Ministry of Health, Labour and Welfare (http://www.mhlw.go.jp/file/06-Seisakujouhou-11130500-Shokuhinanzenbu/0000155147.pdf). It is an almost completely revised version of the 2009 version. The coauthors are 13 specialists in environmental epidemiology, exposure sciences, architecture, and risk communication. Since the 1970s, health problems caused by indoor chemicals, biological pollution, poor temperature control, humidity, and others in office buildings have been recognized as sick building syndrome (SBS) in Western countries, but in Japan it was not until the 1990s that people living in new or renovated homes started to describe a variety of nonspecific subjective symptoms such as eye, nose, and throat irritation, headache, and general fatigue. These symptoms resembled SBS and were designated "sick house syndrome (SHS)." To determine the strategy for prevention of SHS, we conducted a nationwide epidemiological study in six cities from 2003-2013 by randomly sampling 5,709 newly built houses. As a result 1,479 residents in 425 households agreed to environmental monitoring for indoor aldehydes and volatile organic compounds (VOCs). After adjustment for possible risk factors, some VOCs and formaldehyde were dose-dependently shown to be significant risk factors. We also studied the dampness of the houses, fungi, allergies, and others. This book is fully based on the scientific evidence collected through these studies and other newly obtained information, especially from the aspect of architectural engineering. In addition to SHS, we included chapters on recent information about "multi-chemical sensitivity."
  • [House Dust and Its Adverse Health Effects].
    Yu Ait Bamai
    Nihon eiseigaku zasshi. Japanese journal of hygiene, 73, 2, 130, 137, 01 Jan. 2018, [Peer-reviewed], [Domestic magazines]
    Japanese, Scientific journal, In this review, we examine house dust and its effect on inhabitants' health. Residential house dust includes components from plants, pollens, microorganisms, insects, skin flakes, hairs and fibers. It also includes materials contaminated with chemicals from combustion, furniture, interior materials, electronics, cleaning agents, personal care products. Nowadays, most people spend their time indoors. Thus, dust is an important medium of exposure to pollutions. According to United States Environmental Protection Agency Exposure Factors Handbook, the estimated amount of dust ingestion is 30 mg/day for adults, and 60 mg/day for children over 1 year of age. Since 2003, we have been conducting epidemiological studies to find the association between the indoor environment and the inhabitants' health. The levels of mite allergens, endotoxins, and β-1,3-d-glucan in house dust were measured as biological factors. Semi volatile organic compounds (SVOC) such as phthalates and phosphate flame retardants (PFRs) in dust were also analyzed. As a result, we found that the ORs (95%CI) of nasal and optical symptoms of sick building syndrome (SBS) were 1.45 (1.01-2.10) and 1.47 (1.14-1.88), respectively, when there was a 10-fold increase in the levels of mite allergens. There was no association of mite allergens with allergies. Endotoxins and β-1,3-d-glucan did not show any association with SBS. Regarding SVOC, increased levels of phthalates and PFR increased the risk of allergies. The association between phthalates and increased risk of allergies was clearer among children than adults. There were no gold standards of dust sampling and pretreatment methods. Thus, caution is needed when comparing findings of various studies. Methods should accurately reflect exposure levels.
  • [Importance of Two Birth Cohorts (n=20,926 and n=514): 15 Years' Experience of the Hokkaido Study on Environment and Children's Health: Malformation, Development and Allergy].
    Reiko Kishi; Atsuko Araki; Chihiro Miyashita; Sachiko Itoh; Machiko Minatoya; Sumitaka Kobayashi; Keiko Yamazaki; Yu Ait Bamai; Ryu Miura; Naomi Tamura
    Nihon eiseigaku zasshi. Japanese journal of hygiene, 73, 2, 164, 177, 2018, [Peer-reviewed], [Domestic magazines]
    Japanese, Scientific journal, Since "Our Stolen Future" by Theo Colborn was published in 1996, global interest on the impact of chemical substances, such as the endocrine-disrupting action of chemicals, has increased. In Japan, "The Hokkaido Study on Environment and Children's Health: Malformation, Development and Allergy" was launched in 2001. It was a model of Japan Environment and Children's Study of the Ministry of the Environment. In a large-scale, Hokkaido cohort, we obtained the consent of 20,926 mothers at the organogenesis stage with the cooperation of 37 obstetrics clinics in Hokkaido. We tracked the effects of endocrine disruptors on developmental disorders. In a small-scale Sapporo cohort, we observed in detail the neuropsychiatric development of children with the consent of 514 mothers in their late pregnancy. We examined how prenatal exposure to low concentrations of environmental chemicals affect the development of organs and the postnatal development of children. Maternal exposure to POPs, such as PCB/dioxins and perfluorinated alkyl substances, has affected not only children's birth size, thyroid functions, and sex hormone levels, but also postnatal neurodevelopment, infection, and allergy among others. The associations of short-half-life substances, such as DEHP and BPA, with obesity, ASD, and ADHD have been investigated. Gene-environment interactions have been found for smoking, caffeine, folic acid, and PCB/dioxin. In 2015, our center was officially designated as the WHO Collaborating Centre for Environmental Health and Prevention of Chemical Hazards, and we continue to the contribute to the global perspectives of child health.
  • The Hokkaido Birth Cohort Study on Environment and Children's Health: cohort profile-updated 2017
    Reiko Kishi; Atsuko Araki; Machiko Minatoya; Tomoyuki Hanaoka; Chihiro Miyashita; Sachiko Itoh; Sumitaka Kobayashi; Yu Ait Bamai; Keiko Yamazaki; Ryu Miura; Naomi Tamura; Kumiko Ito; Houman Goudarzi
    ENVIRONMENTAL HEALTH AND PREVENTIVE MEDICINE, 22, 1, 46, 46, 2017, [Peer-reviewed], [Domestic magazines]
    English, Scientific journal
  • Exposure to phthalates in house dust and associated allergies in children aged 6-12 years
    Yu Ait Bamai; Atsuko Araki; Toshio Kawai; Tazuru Tsuboi; Ikue Saito; Eiji Yoshioka; Shi Cong; Reiko Kishi
    ENVIRONMENT INTERNATIONAL, 96, 16, 23, Nov. 2016, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • Comparisons of urinary phthalate metabolites and daily phthalate intakes among Japanese families
    Yu Ait Bamai; Atsuko Araki; Toshio Kawai; Tazuru Tsuboi; Eiji Yoshioka; Ayako Kanazawa; Shi Cong; Reiko Kishi
    INTERNATIONAL JOURNAL OF HYGIENE AND ENVIRONMENTAL HEALTH, 218, 5, 461, 470, Jul. 2015, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • Exposure to house dust phthalates in relation to asthma and allergies in both children and adults
    Yu Ait Bamai; Eiji Shibata; Ikue Saito; Atsuko Araki; Ayako Kanazawa; Kanehisa Morimoto; Kunio Nakayama; Masatoshi Tanaka; Tomoko Takigawa; Takesumi Yoshimura; Hisao Chikara; Yasuaki Saijo; Reiko Kishi
    SCIENCE OF THE TOTAL ENVIRONMENT, 485, 153, 163, Jul. 2014, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • Association of Mechanical Ventilation and Flue Use in Heaters With Asthma Symptoms in Japanese Schoolchildren: A Cross-Sectional Study in Sapporo, Japan
    Shi Cong; Atsuko Araki; Shigekazu Ukawa; Yu Ait Bamai; Shuji Tajima; Ayako Kanazawa; Motoyuki Yuasa; Akiko Tamakoshi; Reiko Kishi
    JOURNAL OF EPIDEMIOLOGY, 24, 3, 230, 238, May 2014, [Peer-reviewed], [Domestic magazines]
    English, Scientific journal
  • Detection and intake assessment of organophosphate flame retardants in house dust in Japanese dwellings
    Shuji Tajima; Atsuko Araki; Toshio Kawai; Tazuru Tsuboi; Yu Ait Bamai; Eiji Yoshioka; Ayako Kanazawa; Shi Cong; Reiko Kishi
    SCIENCE OF THE TOTAL ENVIRONMENT, 478, 190, 199, Apr. 2014, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • Associations of phthalate concentrations in floor dust and multi-surface dust with the interior materials in Japanese dwellings
    Yu Ait Bamai; Atsuko Araki; Toshio Kawai; Tazuru Tsuboi; Ikue Saito; Eiji Yoshioka; Ayako Kanazawa; Shuji Tajima; Cong Shi; Akiko Tamakoshi; Reiko Kishi
    SCIENCE OF THE TOTAL ENVIRONMENT, 468, 147, 157, Jan. 2014, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • Epidemiological studies on the environmental pollutants and allergies: Focused on in-door air quality
    Atsuko Araki; Yu Ait Bamai; Reiko Kishi
    Japanese Journal of Allergology, 63, 8, 1075, 1084, Japanese Society of Allergology, 2014, [Peer-reviewed], [Domestic magazines]
    Japanese, Scientific journal
  • Validation of diffusive mini-samplers for aldehyde and VOC and its feasibility for measuring the exposure levels of elementary school children
    Atsuko Araki; Tazuru Tsuboi; Toshio Kawai; Yu Ait Bamai; Tomoya Takeda; Eiji Yoshioka; Reiko Kishi
    JOURNAL OF ENVIRONMENTAL MONITORING, 14, 2, 368, 374, Feb. 2012, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • Building-related symptoms among the elementally school pupils and their association to organic phosphate triesters exposure at home in Sapporo
    Takeda Tomoya; Araki Atsuko; AitBamai Yu; Saito Ikue; Hayakawa Atsushi; Yoshioka Eiji; Kanazawa Ayako; Yuasa Motoyuki; Kishi Reiko
    Hokkaido Journal of Public Health, 24, 2, 73, 84, 北海道公衆衛生学会, Mar. 2011
    Japanese, 札幌市の公立小学校に通う児童78名を対象に、自宅居間の床ダスト中における有機リン酸トリエステル類11化合物の測定を行い、シックハウス症候群(SHS)との関連について検討した。SHS有訴群(39名)と非有訴群(39名)とで11化合物の濃度を比較したところ、全ての化合物において有意な群間差は認められなかった。しかし、化合物のうちリン酸トリスブトキシエチルの濃度は、過去に欧米で報告された濃度に比べてかなり高かったことから、健康影響について更なる調査が必要であると考えられた。
■ Other Activities and Achievements
  • ハウスダストによる有機フッ素化合物の経口曝露推計:北海道スタディ
    藤谷倫子; 原田浩二; アイツバマイ ゆふ; 山口健史; 曾怡; ケテマ ラヒルメスフィン; ケテマ ラヒルメスフィン; 岸玲子; 池田敦子; 池田敦子, 日本衛生学雑誌(Web), 79, Supplement, 2024
  • 化学物質測定データからの疫学・統計解析
    岩田啓芳; アイツバマイ ゆふ; 岸玲子, 環境と測定技術, 51, 10, 2024
  • 化粧品使用による有機フッ素化合物の暴露推計
    藤谷倫子; 原田浩二; 増田秀幸; 山口健史; アイツバマイ ゆふ; 池田敦子; 池田敦子, 日本衛生学雑誌(Web), 78, Supplement, 2023
  • 健康増進に向けた住宅環境整備のための研究 一般家庭における短期/長期堆積ダストを活用した子どものハウスダスト中リン系難燃剤・可塑剤の一日摂取量
    池田敦子; 金勲; アイツバマイ ゆふ; 岸玲子; 戸次加奈江; 稲葉洋平, 健康増進に向けた住宅環境整備のための研究 令和3年度 総括・分担研究報告書(Web), 2022
  • 思春期のパーソナルケア製品の使用状況:北海道スタディ
    増田秀幸; アイツバマイ ゆふ; 藤谷倫子; 山口健史; 宮下ちひろ; 岸玲子; 橘田岳也; 中村明枝; 原田真理子; 原田浩二; 池田(荒木)敦子; 池田(荒木)敦子, 日本衛生学雑誌(Web), 77, Supplement, 2022
  • 日用品中のフタル酸エステル,ビスフェノール等の含有量調査
    原田浩二; 藤谷倫子; 呂兆卿; 増田秀幸; 山口健史; アイツバマイ ゆふ; 池田(荒木)敦子; 池田(荒木)敦子, 日本衛生学雑誌(Web), 77, Supplement, 2022
  • 胎児期フタル酸エステル類曝露による思春期発来への影響 北海道スタディ
    山口健史; 山口健史; 池田敦子; 池田敦子; アイツバマイ ゆふ; アイツバマイ ゆふ; 宮下ちひろ; 池中良徳; 池中良徳; 中村明枝; 今雅史; 藤谷倫子; 原田浩二; 岸玲子, DOHad研究(Web), 10, 2, 2022
  • Childhood allergies and obesity relationship: Identification of novel non-invasive biomarkers
    Houman Goudarzi; Satoshi Konno; Atsuko Araki; Sachiko Ito; Yu Ait Bamai; Chihiro Miyashita; Reiko Kishi, EUROPEAN RESPIRATORY JOURNAL, 54, Sep. 2019
    English, Summary international conference
  • 学童の尿中リン酸トリエステル類代謝物濃度と尿中炎症関連マーカーとの関連
    アイツバマイ ゆふ; Bastiaensen Michiel; 荒木 敦子; Houman Goudarzi; 今野 哲; 伊藤 佐智子; 宮下 ちひろ; Covaci Adrian; 岸 玲子, 日本衛生学雑誌, 74, Suppl., S116, S116, Feb. 2019
    (一社)日本衛生学会, Japanese
  • 学童の尿中リン酸トリエステル類代謝物濃度と尿中炎症関連マーカーとの関連
    アイツバマイ ゆふ; Bastiaensen Michiel; 荒木 敦子; Houman Goudarzi; 今野 哲; 伊藤 佐智子; 宮下 ちひろ; Covaci Adrian; 岸 玲子, 日本衛生学雑誌, 74, Suppl., S116, S116, Feb. 2019
    (一社)日本衛生学会, Japanese
  • エコチル調査北海道ユニットセンターの進捗状況と、2歳までの喘鳴および湿疹の有病割合に関する報告
    荒木 敦子; 西條 泰明; 伊藤 善也; アイツバマイ ゆふ; 宮下 ちひろ; 伊藤 佐智子; 小林 澄貴; 湊屋 街子; 山崎 圭子; 三浦 りゅう; 吉岡 英治; 川西 康之; 村林 宏; 佐藤 遊洋; 岸 玲子, 環境ホルモン学会研究発表会要旨集, 21回, 100, 100, Dec. 2018
    環境ホルモン学会(日本内分泌撹乱化学物質学会), Japanese
  • エコチル調査北海道ユニットセンターの進捗状況と、2歳までの喘鳴および湿疹の有病割合に関する報告
    荒木 敦子; 西條 泰明; 伊藤 善也; アイツバマイ ゆふ; 宮下 ちひろ; 伊藤 佐智子; 小林 澄貴; 湊屋 街子; 山崎 圭子; 三浦 りゅう; 吉岡 英治; 川西 康之; 村林 宏; 佐藤 遊洋; 岸 玲子, 環境ホルモン学会研究発表会要旨集, 21回, 100, 100, Dec. 2018
    環境ホルモン学会(日本内分泌撹乱化学物質学会), Japanese
  • 室内ダスト中リン酸トリエステル類とその尿中代謝物濃度と学童の喘鳴・アレルギー症状との関連 札幌市学童調査
    荒木 敦子; アイツバマイ ゆふ; Bastiaensen Michiel; Van den Eede Nele; 河合 俊夫; 坪井 樹; Ketema Rahel Mesfin; Covaci Adrian; 岸 玲子, 北海道公衆衛生学雑誌, 32, 1特別付録, 66, 66, Oct. 2018
    北海道公衆衛生学会, Japanese
  • 小型携帯サンプラーを用いた学童の化学物質曝露と自宅環境中濃度との関連
    荒木敦子; 河合俊夫; 坪井樹; アイツバマイ ゆふ; 岸玲子, 産業衛生学雑誌, 60, 臨増, 416, 416, 16 May 2018
    (公社)日本産業衛生学会, Japanese
  • 【住環境における健康リスク要因とそのマネジメント】 室内環境中のハウスダストによる健康影響
    荒木 敦子; アイツバマイ ゆふ; ラヘル・メスフィン・ケテマ; 岸 玲子, 日本衛生学雑誌, 73, 2, 130, 137, May 2018
    2003年より室内環境と居住者の健康に関する疫学研究を実施し、ダスト中のダニアレルゲン、微生物由来成分、準揮発性有機化合物を測定してきた。これら疫学研究の結果から、特にハウスダストに焦点を当て、健康影響としてシックハウス症候群やアレルギー症状との関連について概説した。最後に、ダストを用いた曝露評価の課題について述べた。, (一社)日本衛生学会, Japanese
  • 【小児環境保健疫学研究のパラダイム】 2万人規模の出生コーホートと、500人規模の小コーホートからなる北海道スタディが目指してきたもの 環境と子どもの健康 先天異常・発達・アレルギーの15年におよぶ経験と成果
    岸 玲子; 荒木 敦子; 宮下 ちひろ; 伊藤 佐智子; 湊屋 街子; 小林 澄貴; 山崎 圭子; アイツバマイ ゆふ; 三浦 りゅう; 田村 菜穂美, 日本衛生学雑誌, 73, 2, 164, 177, May 2018
    2001年より胎児期からの環境曝露影響を前向きに研究する「環境と子供の健康に関する北海道スタディー」を立ち上げた。これは2万人規模と500人規模の大小2つの前向きコーホートから構成されている。1)北海道スタディーの背景と目的、特徴、2)追跡の時系列デザインと測定項目、3)北海道スタディーでこれまでに得られた成果、4)北海道スタディーの今後の課題と提言、について概説した。, (一社)日本衛生学会, Japanese
  • 【住環境における健康リスク要因とそのマネジメント】 室内環境中のハウスダストによる健康影響
    荒木 敦子; アイツバマイ ゆふ; ラヘル・メスフィン・ケテマ; 岸 玲子, 日本衛生学雑誌, 73, 2, 130, 137, May 2018
    2003年より室内環境と居住者の健康に関する疫学研究を実施し、ダスト中のダニアレルゲン、微生物由来成分、準揮発性有機化合物を測定してきた。これら疫学研究の結果から、特にハウスダストに焦点を当て、健康影響としてシックハウス症候群やアレルギー症状との関連について概説した。最後に、ダストを用いた曝露評価の課題について述べた。, (一社)日本衛生学会, Japanese
  • 【小児環境保健疫学研究のパラダイム】 2万人規模の出生コーホートと、500人規模の小コーホートからなる北海道スタディが目指してきたもの 環境と子どもの健康 先天異常・発達・アレルギーの15年におよぶ経験と成果
    岸 玲子; 荒木 敦子; 宮下 ちひろ; 伊藤 佐智子; 湊屋 街子; 小林 澄貴; 山崎 圭子; アイツバマイ ゆふ; 三浦 りゅう; 田村 菜穂美, 日本衛生学雑誌, 73, 2, 164, 177, May 2018
    2001年より胎児期からの環境曝露影響を前向きに研究する「環境と子供の健康に関する北海道スタディー」を立ち上げた。これは2万人規模と500人規模の大小2つの前向きコーホートから構成されている。1)北海道スタディーの背景と目的、特徴、2)追跡の時系列デザインと測定項目、3)北海道スタディーでこれまでに得られた成果、4)北海道スタディーの今後の課題と提言、について概説した。, (一社)日本衛生学会, Japanese
  • 胎児期の有機フッ素化合物曝露が7歳のアレルギーに及ぼす影響 北海道スタディ
    アイツバマイ ゆふ; 荒木 敦子; 宮下 ちひろ; 岡田 恵美子; 樫野 郁子; グウダルジ・ホウマヌ; 松浦 英幸; 岸 玲子, 日本衛生学雑誌, 73, Suppl., S225, S225, Mar. 2018
    (一社)日本衛生学会, Japanese
  • 尿中リン酸とトリエステル類と児の喘息・アレルギーとの関連 札幌市学童調査
    荒木 敦子; アイツバマイ ゆふ; バスチャンセン・ミキエル; ファンデンイーデ・ネール; ケテマ・ラヘル; 伊藤 佐智子; 宮下 ちひろ; コバチ・アドリアン; 岸 玲子, 日本衛生学雑誌, 73, Suppl., S234, S234, Mar. 2018
    (一社)日本衛生学会, Japanese
  • 尿中リン酸トリエステル類と児の喘息・アレルギーとの関連―札幌市学童調査
    荒木敦子; アイツバマイ ゆふ; バスチャンセン ミキエル; ファンデンイーデ ネール; ケテマ ラヘル; ケテマ ラヘル; 伊藤佐智子; 宮下ちひろ; コバチ アドリアン; 岸玲子, 日本衛生学雑誌(Web), 73, Supplement, S234, Mar. 2018
    Japanese
  • 胎児期の有機フッ素化合物曝露が7歳のアレルギーに及ぼす影響 北海道スタディ
    アイツバマイ ゆふ; 荒木 敦子; 宮下 ちひろ; 岡田 恵美子; 樫野 郁子; グウダルジ・ホウマヌ; 松浦 英幸; 岸 玲子, 日本衛生学雑誌, 73, Suppl., S225, S225, Mar. 2018
    (一社)日本衛生学会, Japanese
  • 尿中リン酸トリエステル類と児の喘息・アレルギーとの関連 札幌市学童調査
    荒木 敦子; アイツバマイ ゆふ; バスチャンセン・ミキエル; ファンデンイーデ・ネール; ケテマ・ラヘル; 伊藤 佐智子; 宮下 ちひろ; コバチ・アドリアン; 岸 玲子, 日本衛生学雑誌, 73, Suppl., S234, S234, Mar. 2018
    (一社)日本衛生学会, Japanese
  • 胎児期の有機フッ素化合物曝露が7歳のアレルギーに及ぼす影響-北海道スタディ
    アイツバマイ ゆふ; 荒木敦子; 宮下ちひろ; 岡田恵美子; 岡田恵美子; 樫野郁子; 樫野郁子; グウダルジ ホウマヌ; グウダルジ ホウマヌ; 松浦英幸; 岸玲子, 日本衛生学雑誌(Web), 73, Supplement, 2018
  • Effects of Environmental Chemicals in Indoor Air and House Dust on Inhabitant Health
    アイツバマイ ゆふ; 荒木 敦子; 岸 玲子, 環境技術, 46, 7, 372, 377, Jul. 2017
    環境技術学会, Japanese
  • 住環境における健康リスク要因とそのマネジメント 室内環境中のハウスダストによる健康影響
    荒木 敦子; アイツバマイ ゆふ; 岸 玲子, 日本衛生学雑誌, 72, Suppl., S138, S138, Mar. 2017
    (一社)日本衛生学会, Japanese
  • 住環境における健康リスク要因とそのマネジメント 科学的エビデンスに基づく「シックハウス症候群相談マニュアル改訂版」の作成について
    岸 玲子; 東 賢一; 西條 泰明; 柴田 英治; 田中 正敏; 河合 俊夫; 大和 浩; 吉野 博; 大澤 元毅; 増地 あゆみ; 荒木 敦子; アイツバマイ ゆふ; 湊屋 街子, 日本衛生学雑誌, 72, Suppl., S138, S138, Mar. 2017
    (一社)日本衛生学会, Japanese
  • 胎児期BPA曝露による7歳までの喘鳴・アトピー性皮膚炎への影響 北海道スタディ
    アイツバマイ ゆふ; 宮下 ちひろ; 荒木 敦子; 湊屋 街子; 山本 潤; 松村 徹; 佐々木 成子; 岸 玲子, 日本衛生学雑誌, 72, Suppl., S198, S198, Mar. 2017
    (一社)日本衛生学会, Japanese
  • ダイオキシン類の胎児期曝露による児のアレルギーへの影響 北海道スタディ
    宮下 ちひろ; 荒木 敦子; 伊藤 佐智子; 湊屋 街子; 小林 澄貴; アイツバマイ ゆふ; 梶原 淳睦; 戸高 尊; 岸 玲子, 日本衛生学雑誌, 72, Suppl., S199, S199, Mar. 2017
    (一社)日本衛生学会, Japanese
  • 「シックハウス症候群に関する相談マニュアル改訂新版」の作成 公衆衛生分野での活用に向けて
    荒木 敦子; アイツバマイ ゆふ; 西條 泰明; 湊屋 街子; 吉野 博; 東 賢一; 河合 俊夫; 大和 浩; 大澤 元毅; 柴田 英治; 田中 正敏; 増地 あゆみ; 岸 玲子, 北海道公衆衛生学雑誌, 30, 1特別付録, 55, 55, Oct. 2016
    北海道公衆衛生学会, Japanese
  • 環境省「エコチル調査」開始4年を経ての集計結果の報告 全国と北海道の参加者の喫煙・食物アレルギー等について
    土川 陽子; 西條 泰明; 伊藤 善也; 吉岡 英治; 川西 康之; 堤 裕幸; 遠藤 俊明; 馬場 剛; 小林 正樹; 水上 尚典; 有賀 正; 長 和俊; 白石 秀明; 千石 一雄; 宮本 敏伸; 東 寛; 荒木 敦子; 池野 多美子; 宮下 ちひろ; 伊藤 佐智子; 湊屋 街子; 小林 澄貴; アイツバマイ ゆふ; 山崎 圭子; 西原 進吉; 田村 菜穂美; 岸 玲子, 北海道母性衛生学会誌, 45, 33, 38, Aug. 2016
    北海道母性衛生学会, Japanese
  • FLG変異とフタル酸エステル曝露による児のADへの影響 北海道スタディ
    アイツバマイ ゆふ; 荒木 敦子; 乃村 俊史; 河合 俊夫; 坪井 樹; 叢 石; 宮下 ちひろ; 池野 多美子; 清水 宏; 岸 玲子, 日本衛生学雑誌, 71, Suppl., S192, S192, May 2016
    (一社)日本衛生学会, Japanese
  • 北海道のエコチル調査の集計結果 生後2歳までの食物アレルギーの頻度および食品の摂食状況について
    アイツバマイ ゆふ; 西條 泰明; 伊藤 善也; 村林 宏; 吉岡 英治; 川西 康之; 水上 尚典; 有賀 正; 長和 俊; 白石 秀明; 千石 一雄; 宮本 敏伸; 東 寛; 堤 裕幸; 遠藤 俊明; 馬場 剛; 小林 正樹; 荒木 敦子; 池野 多美子; 宮下 ちひろ; 伊藤 佐智子; 土川 陽子; 湊屋 街子; 小林 澄貴; 山崎 圭子; 西原 進吉; 田村 菜穂美; 岸 玲子, 北海道公衆衛生学雑誌, 29, 1特別付録, 36, 36, Nov. 2015
    北海道公衆衛生学会, Japanese
  • 環境化学物質の曝露実態(4)短半減期化学物質の曝露実態
    荒木敦子; アイツバマイゆふ; 岸玲子, 公衆衛生, 79, 7, 2015
  • 乳幼児のアレルギーと胎児期・小児期の可塑剤,難燃剤曝露
    荒木敦子; アイツバマイゆふ; 岸玲子, 公衆衛生, 79, 11, 876, 881, 2015
    医学書院, Japanese
  • 環境汚染とアレルギーに関する疫学的知見;特に室内空気質に焦点をあてて
    荒木敦子; アイツバマイゆふ; 岸玲子, アレルギー, 63, 7, 1075, 1083, 2014
  • 住環境に置けるフタル酸エステル類・リン酸トリエステル類の曝露実態と住居者への健康影響
    荒木敦子; アイツバマイゆふ; 岸玲子, 空気清浄, 52, 3, 170, 177, 2014
  • 札幌市128軒のハウスダスト中リン酸トリエステル類濃度と小学生のアレルギー疾患との関連
    多島 秀司; 荒木 敦子; 河合 俊夫; 坪井 樹; アイツバマイ ゆふ; 叢 石; 吉岡 英治; 岸 玲子, 北海道公衆衛生学雑誌, 27, 1特別付録, 44, 44, Nov. 2013
    北海道公衆衛生学会, Japanese
  • 札幌市内小学生の自宅における暖房、および機械換気の有無と児童の喘息
    叢 石; 荒木 敦子; 鵜川 重和; アイツバマイ ゆふ; 多島 秀司; 金澤 文子; 湯浅 資之; 玉腰 暁子; 岸 玲子, 北海道公衆衛生学雑誌, 27, 1特別付録, 45, 45, Nov. 2013
    北海道公衆衛生学会, Japanese
  • 尿中フタル酸代謝物濃度とハウスダスト中フタル酸エステル濃度との関連 札幌市児童における調査
    アイツバマイ ゆふ; 荒木 敦子; 河合 俊夫; 坪井 樹; 多島 秀司; 叢 石; 湯浅 資之; 金澤 文子; 玉腰 暁子; 岸 玲子, 北海道公衆衛生学雑誌, 27, 1特別付録, 47, 47, Nov. 2013
    北海道公衆衛生学会, Japanese
  • GC/MSによるヒトの尿中2-エチルヘキサノールの定量 フタル酸ジエステル類評価としての無水フタル酸可塑剤・難燃剤曝露と小児の健康影響
    河合 俊夫; 坪井 樹; 荒木 敦子; アイツバマイ ゆふ; 岸 玲子, 産業衛生学雑誌, 55, 臨増, 439, 439, May 2013
    (公社)日本産業衛生学会, Japanese
  • フタル酸エステル尿中代謝物の同時測定方法の開発可塑剤難燃剤曝露と小児の健康影響(1)
    坪井 樹; 河合 俊夫; 荒木 敦子; アイツバマイ ゆふ; 岸 玲子, 日本衛生学雑誌, 68, Suppl., S159, S159, Mar. 2013
    (一社)日本衛生学会, Japanese
  • アレルギーとダスト中フタル酸エステル濃度 可塑剤・難燃剤曝露と小児の健康影響(3)
    アイツバマイ ゆふ; 荒木 敦子; 坪井 樹; 河合 俊夫; 多島 秀司; 叢 石; 吉岡 英治; 玉腰 暁子; 岸 玲子, 日本衛生学雑誌, 68, Suppl., S159, S159, Mar. 2013
    (一社)日本衛生学会, Japanese
  • フタル酸ジエステル類評価としての無水フタル酸可塑剤・難燃剤曝露と小児の健康影響(2)
    河合 俊夫; 坪井 樹; 荒木 敦子; アイツバマイ ゆふ; 岸 玲子, 日本衛生学雑誌, 68, Suppl., S204, S204, Mar. 2013
    (一社)日本衛生学会, Japanese
  • 児童の尿中フタル酸代謝物濃度とアレルギー 可塑剤、難燃剤の小児への健康影響(4)
    荒木 敦子; 坪井 樹; 河合 俊夫; アイツバマイ ゆふ; 多島 秀司; 叢 石; 鵜川 重一; 吉岡 英治; 岸 玲子, 日本衛生学雑誌, 68, Suppl., S204, S204, Mar. 2013
    (一社)日本衛生学会, Japanese
  • 可塑剤・難燃剤の曝露評価手法の開発と小児アレルギー・リスク評価への応用 尿中2-エチル-1-ヘキサノールの分析方法と測定事例
    河合 俊夫; 坪井 樹; 荒木 敦子; アイツバマイゆふ; 岸 玲子, 産業衛生学雑誌, 55, 1, 36, 36, Jan. 2013
    (公社)日本産業衛生学会, Japanese
  • ハウスダスト中フタル酸エステルと住環境との関連
    アイツバマイゆふ; 荒木敦子; 河合俊夫; 坪井樹; 斎藤育江; 吉岡栄治; 金澤文子; 多島秀司; 叢石; 玉腰暁子; 岸玲子, 北海道医学雑誌, 88, 6, 2013
  • 小学生の住宅におけるハウスダスト中のエンドトキシンならびにβ-グルカン量とアレルギー性疾患に関する研究
    叢 石; 荒木 敦子; アイツバマイ ゆふ; 竹田 智哉; 早川 敦司; 吉岡 英治; 多島 秀司; 鵜川 重和; 玉腰 暁子; 岸 玲子, 北海道公衆衛生学雑誌, 26, 1特別付録, 33, 33, Nov. 2012
    北海道公衆衛生学会, Japanese
  • ハウスダスト中に含まれるリン酸トリエステル類の濃度と住居環境
    多島 秀司; 荒木 敦子; 坪井 樹; 河合 俊夫; 斎藤 育江; アイツバマイ ゆふ; 竹田 智哉; 鵜川 重和; 吉岡 英治; 岸 玲子, 北海道公衆衛生学雑誌, 26, 1特別付録, 34, 34, Nov. 2012
    北海道公衆衛生学会, Japanese
  • 札幌市小学生の喘息・鼻結膜炎有訴と自宅環境および気中VOC・MVOC濃度
    荒木 敦子; アイツバマイ ゆふ; 河合 俊夫; 坪井 樹; 竹田 智哉; 多島 秀司; 鵜川 重和; 叢 石; 吉岡 英治; 岸 玲子, 日本衛生学雑誌, 67, 2, 285, 285, Feb. 2012
    (一社)日本衛生学会, Japanese
  • 小学生のシックハウス症候群の有訴と床ダスト中有機リン酸トリエステル類濃度との関係
    多島 秀司; 荒木 敦子; 斎藤 育江; 河合 俊夫; 坪井 樹; アイツバマイ ゆふ; 竹田 智哉; 吉岡 英治; 鵜川 重和; 岸 玲子, 日本衛生学雑誌, 67, 2, 285, 285, Feb. 2012
    (一社)日本衛生学会, Japanese
  • 室内空気質中フタル酸エステル類曝露とアレルギーへの影響
    アイツバマイ ゆふ; 荒木 敦子; 岸 玲子, Endocrine Disrupter News Letter, 15, 1, 2, 2, 2012
    日本内分泌撹乱化学物質学会(環境ホルモン学会), Japanese
  • 自宅空気中化学物質濃度とシックハウス症候群に関する調査研究 札幌市小学生を対象として
    荒木 敦子; アイツバマイ ゆふ; 坪井 樹; 河合 俊夫; 竹田 智哉; 早川 敦司; 吉岡 英治; 多島 秀司; 叢 石; 鵜川 重和; 岸 玲子, 北海道公衆衛生学雑誌, 25, 1特別付録, 50, 50, Nov. 2011
    北海道公衆衛生学会, Japanese
  • 自宅住環境とアトピー性皮膚炎に関する調査 札幌市の小学生4,500名を対象として
    鵜川 重和; 荒木 敦子; 金澤 文子; 湯浅 資之; アイツバマイ ゆふ; 吉岡 英治; 叢 石; 多島 秀司; 岸 玲子, 北海道公衆衛生学雑誌, 25, 1特別付録, 51, 51, Nov. 2011
    北海道公衆衛生学会, Japanese
  • 小学生の住宅におけるハウスダスト中のエンドトキシンならびにβ-グルカン量と住宅特徴に関する調査
    叢 石; 荒木 敦子; アイツバマイ ゆふ; 竹田 智哉; 早川 敦司; 吉岡 英治; 多島 秀司; 鵜川 重和; 岸 玲子, 北海道公衆衛生学雑誌, 25, 1特別付録, 54, 54, Nov. 2011
    北海道公衆衛生学会, Japanese
■ Syllabus
  • 大学院共通授業科目(教育プログラム):社会と健康, 2024年, 修士課程, 大学院共通科目
  • 大学院共通授業科目(教育プログラム):社会と健康, 2024年, 修士課程, 大学院共通科目
  • 大学院共通授業科目(教育プログラム):社会と健康, 2024年, 修士課程, 大学院共通科目
■ Affiliated academic society
  • 2018 - Present
    International Society of Exposure Science
  • 2015 - Present
    International Society for Environmental Epidemiology
  • 2010 - Present
    THE JAPANESE SOCIETY FOR HYGIENE
■ Research Themes
  • Epigenomic Modifications and Health Implications of Plastic Additives: A Comprehensive Human and Cell Study
    Grants-in-Aid for Scientific Research
    01 Apr. 2025 - 31 Mar. 2029
    池田 敦子; 曾 怡; 小島 弘幸; 池中 良徳; KETEMA RAHEL・MESFIN; MEGASARI MARSELA; 山口 健史; アイツバマイ ゆふ
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (A), Hokkaido University, 25H01075
  • The association between multiple environmental exposures and ADHD symptoms
    Grants-in-Aid for Scientific Research
    01 Apr. 2025 - 31 Mar. 2029
    山崎 圭子; 池田 敦子; 須山 聡; アイツバマイ ゆふ; 山本 理恵子
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (C), Hokkaido University, 25K13557
  • フタル酸エステル類曝露と体組成:幼児期から思春期の運動習慣を加味した長期縦断研究
    科学研究費助成事業
    Apr. 2025 - Mar. 2029
    牧野 圭太郎; 山口 健史; アイツバマイ ゆふ
    日本学術振興会, 基盤研究(C), 北海道大学, 25K14858
  • プラスチック添加剤によるエピゲノム変化と健康影響:ヒトと細胞の融合的アプローチ
    科学研究費助成事業
    Apr. 2025 - Mar. 2029
    アイツバマイ ゆふ; 山口 健史; MEGASARI MARSELA; KETEMA RAHEL; MESFIN; 池中 良徳; 小島 弘幸; 池田 敦子
    文部科学省, 北海道大学, Coinvestigator, 25044750
  • Impact of Chemical Exposure on Reproductive Health from Fetal Life: Unraveling Molecular Mechanisms
    Grants-in-Aid for Scientific Research
    Apr. 2025 - Mar. 2029
    岸 玲子; アイツバマイ ゆふ; 山口 健史; 伊藤 佐智子; 岩田 啓芳; 牧野 圭太郎; 田村 菜穂美; 馬場 剛; 齊藤 良玄; 江口 哲史; 今 雅史; 村西 雄貴; 平田 由里絵
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (A), Hokkaido University, 25H01076
  • Health research of local residents in an informal e-waste processing villege in Vietnam
    Grants-in-Aid for Scientific Research
    07 Oct. 2022 - 31 Mar. 2027
    池田 敦子; RAHEL MESFIN・KETEMA; 宮下 ちひろ; アイツバマイ ゆふ
    ベトナムの研究者と協力し、ベトナムにおけるこれまでの電気・電子機器廃棄物(E-waste)に関係する研究の文献レビューを実施した。非正規の電子廃棄物(e-waste)解体活動は、環境中に有害化合物を放出し、環境や健康に有害な影響を与える可能性がある。そこで本レビューでは、ベトナムにおけるe-waste処理に伴い排出される有害化学物質とその健康影響に言及した文献検索を実施した。ベトナムで関連する21の研究論文を抽出し、e-waste作業施設の粉塵、土壌、大気、堆積物などの汚染実態、ヒトの毛髪、血清、母乳サンプルを用いてた曝露評価に関する論文が報告されていた。E-waste地域とe-wasteの処理のない地域における暴露レベルを比較した研究では、E-waste地域の環境および生体サンプルの両方で、PBDE、PCB、重金属のレベルが高いことが確認された。E-waste処理地域では、作業者の血清サンプルからは年齢と相関してPCBレベルが高くなることが報告されていた。重金属のうち、鉛は飲料水、室内土壌、生体サンプルから高濃度検出された。また、米中からなNi、土壌や食事中のMn、粉塵中のZn、尿中のAs高濃度も検出された。ヒトバイオモニタリングでは、e-waste処理地域の子どもや母親は、e-waste処理地域外の調査参加者よりも高い健康リスクを有することが示された。このレビュー論文は、Reviews on Environmental Healthに発表した。
    さらに、ベトナム研究者と研究打ち合わせを行い、調査プロトコールを作成中である。また、ベトナム側の参加機関としてベトナムNational Institute of Occupational and Environmental Healthの協力を得て、調査許可に向けた協力覚書を準備する予定である。
    Japan Society for the Promotion of Science, Fund for the Promotion of Joint International Research (Fostering Joint International Research (B)), Hokkaido University, 22KK0142
  • Effects of exposure to environmental chemicals on adolescent reproductive function, depression, and NCDs in the Hokkaido Study: Clarification of molecular mechanism
    Grants-in-Aid for Scientific Research
    01 Apr. 2022 - 31 Mar. 2026
    岸 玲子; 齊藤 卓弥; 池田 敦子; 山崎 圭子; 田村 菜穂美; 山口 健史; 宮下 ちひろ; 伊藤 佐智子; アイツバマイ ゆふ; 小林 澄貴
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (A), Hokkaido University, 22H00489
  • Bridging Health: Integrating Child, Adolescent and Young Adult Well-Being Across Melbourne and Hokkaido Through Cohort Studies
    Hokkaido-Melbourne Joint Research Workshops Fund 2025
    Apr. 2025 - Mar. 2026
    Hokkaido University, International Workshops Fund, Hokkaido University, Principal investigator
  • Exploring legacy and novel PFAS exposure Profiles and their Relation to children's Immune funcTion (ESPRIT)
    Grants-in-Aid for Scientific Research
    01 Apr. 2022 - 31 Mar. 2025
    アイツバマイ ゆふ; 池田 敦子; 岸 玲子; 山口 健史; KETEMA RAHEL・MESFIN; MEGASARI MARSELA; 宮下 ちひろ
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Hokkaido University, 23K25013
  • 有機フッ素化合物および新規類縁化合物の曝露実態と児の免疫系への健康影響の解明
    科学研究費助成事業
    01 Apr. 2022 - 31 Mar. 2025
    アイツバマイ ゆふ; 池田 敦子; 宮下 ちひろ; 岸 玲子; 山口 健史
    日本学術振興会, 基盤研究(B), 北海道大学, 22H03759
  • Adverse health effects of environmental chemical exposure: elucidation of mechanisms via human and animal studies
    Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (A)
    05 Apr. 2021 - 31 Mar. 2025
    荒木 敦子; 小島 弘幸; 増田 秀幸; 池中 良徳; Goudarzi Houman; POUDEL KRITIKA; 中村 明枝; アイツバマイ ゆふ
    疫学研究では、「北海道スタディ」に参加する9-11歳の前思春期児から収集した血漿を用いて、購入したBio-Plex200 multiplexアッセイシステムによりTh1/Th2関連サイトカイン17種類およびエオタキシン、糖尿病マーカー10種類およびアディポネクチンとアディプシンを約420検体測定した。同様に、9-11歳の学童339人の血漿を用いて、独自に開発した内標準物質による定量LC/MS分析法を利用し、血中各種コレステリルエステル(CE)11化合物の濃度測定を行った。なお、CE濃度が他のパラメーター、例えば性別や年齢、体格と関連性については現在解析中である。一般集団の子どもにおけるT2バイオマーカー(総IgE、好酸球、呼気中一酸化窒素(FeNO))の基準値を求めた。喘鳴、鼻結膜炎、湿疹といったアレルギー症状に加えて、性別(男児)と喫煙がT2バイオマーカー値を説明していた。
    リン酸トリエステル類曝露とT2バイオマーカーである血中総IgE、好酸球、FeNO、および表現型としての喘鳴、湿疹、鼻結膜炎の症状との関連を解析し、リン酸トリエステル類ΣTBOEPとΣTPHP濃度が高いと喘息、好酸球およびFeNOのリスクが高くなることが明らかになった。
    妊娠ICRマウスに、水(対照群)、PFOA 0.3 mg/kg(低用量群)及びPFOA 3 mg/kg(高用量群)を妊娠期間中経口曝露した。それぞれ出生後7日目の仔マウス肝臓からmRNAを採取した。GeneChip解析を用いた網羅的遺伝子発現解析を行い、PFOA投与量に応じて変動遺伝子数の上昇を認めた。また、高用量群マウスから生まれた仔マウスの肝臓は肥大しており、PFOAが胎盤や母乳を介して仔に影響したと考えられた。
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (A), Hokkaido University, 21H04843
  • Elucidation of effects of prenatal environment on neurodevelopmental disorders, brain sex differentiation and obesity: a birth cohort study
    Grants-in-Aid for Scientific Research
    01 Apr. 2019 - 31 Mar. 2023
    Kishi Reiko
    In this study, we prospectively followed a birth cohort of children as a life-course epidemiological study. We evaluated the effects on developmental disorders such as ADHD (Attention Deficit Hyperactivity Disorder) and their underlying "cognitive characteristics" from school age to adolescence. Additionally, the effects on brain sex differentiation, the onset of the secondary sexual characteristics at puberty, and the presence or absence of increased risk of obesity in children who were underweight at birth were investigated. The association between fetal exposure to MEHPs and ADHD at age 6 years was increased with prenatal exposure to MEHPs, but this association disappeared at age 8 years.
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (A), Hokkaido University, 19H01071
  • 環境化学物質の複合曝露による思春期の健康影響評価と曝露源 の検討
    環境研究総合推進費
    Apr. 2020 - Mar. 2023
    荒木敦子; アイツバマイゆふ; 宮下ちひろ; 増田秀幸; 中村明枝; 橘田岳也; 岸玲子; 篠原信雄、真部淳; 原田浩二; 藤谷倫子、原田真理子
    独立行政法人 環境再生保全機構環, Coinvestigator
  • Evaluation of association between adipocytokines and childhood obesity and asthma: birth cohort study
    Grants-in-Aid for Scientific Research
    01 Apr. 2019 - 31 Mar. 2022
    Miyashita Chihiro
    In a prospective birth cohort, the aim in this study was evaluated association between child obesity in early life and asthma in school-aged children. This study suggests that obesity at age 4 years were practical risk factor for wheezing symptoms at age 7 years. In a case-control study, increased concentration of interleukin 6 (IL 6) in cord blood, which is inflammatory cytokine were associated with increased incidence of obesity with sixth grade school children in boys. The result indicates that IL6 levels at birth may be associated with obesity risk factor, especially in boys. On the other hand, childhood obesity was not associated with asthma at age 12, suggesting that the association between childhood obesity and asthma may change at the age of puberty.
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (C), Hokkaido University, 19K10636
  • Effects of pre-pubertal exposure to phthalate and phosphorous flame retardants on pubertal developments in Japanese children
    Grants-in-Aid for Scientific Research
    01 Apr. 2019 - 31 Mar. 2022
    Ait Bamai Yu
    The aim of this study was to prospectively examine the effects of single and combined exposure to PFRs and phthalates before puberty on the onset of pubertal development in children in the prospective birth cohort, the Hokkaido Study. The outcomes of pubertal development children at the age of 12 years were assessed from the 12-year-old questionnaire; 10 urinary metabolites of phthalate were determined by LC-MS/MS from first morning void urine samples collected at the age of 7 years.
    The results of the present study are consistent with previous findings showing that exposure to phthalates delays the onset of puberty. However, caution is needed in interpreting the results as the exposure was assessed in urine at one point in time at the age of 7 years. Future studies will examine the effects of combined exposure to other chemicals for which exposure assessments have been completed in 7-year-old children.
    Japan Society for the Promotion of Science, Grant-in-Aid for Early-Career Scientists, Hokkaido University, 19K20457
  • Perfluorinated alkyl substances exposure and onset of puberty - birth cohort and in vitro studies
    Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)
    01 Apr. 2018 - 31 Mar. 2022
    Ikeda Atsuko
    Per and polyfluorinated substances (PFAS) is a class of chemicals known for "endocrine disrupting” effects. A birth cohort study examined the effects of prenatal PFAS exposure on gonadal function and onset of puberty. Prenatal PFAS exposure lowered testosterone levels and increased progesterone and INSL3 levels at birth. PFTrDA delayed the age of menarche in girls. ESR1 polymorphisms may modulate the effects of PFAS on sexual differentiation. In vitro study, PFOA and PFNA showed agonist activity of ERalpha and PPARalpha. PFOA and PFNA were agonists of ERalpha and PPARalpha, whereas no agonist of antagonist activation of ERbeta, AR, GR, TR. Up or down regulation of about 800-intracellular gene expression were observed upon PFOA exposure, including PPARalpha receptors signaling genes and cytokines and IgE related genes.
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Hokkaido University, 18H03035
  • 環境化学物質の複合曝露による 喘息・アレルギー、免疫系へ及ぼす影響の解明
    環境研究総合推進費
    Apr. 2017 - Mar. 2020
    荒木敦子; 岸玲子; アイツバマイゆふ; 宮下ちひろ; 伊藤佐智子; 湊屋街子; 小林澄貴; 三浦りゅう; 有賀正; 西村正治; 今野哲; ゴウダルジホウマヌ
    独立行政法人 環境再生保全機構環, Coinvestigator
  • Prepubertal exposure to phthalates and sexual maturation among 12 years old children: Hokkaido Study
    Grants-in-Aid for Scientific Research Grant-in-Aid for Young Scientists (B)
    01 Apr. 2016 - 31 Mar. 2019
    Ait Bamai Yu
    Aim of this study is to investigate the association between prepubertal exposure to phthalates and sexual maturation among 12 years old children. The guardians of 12 years old children answered a questionnaire covering questions about breaking of voice (boys only), menarche and breast growth (girls only), and pubic hair growth (boys and girls). Ten phthalate metabolites from child’s urine taken when they were 7 years old were measured by LC-MS/MS to assess phthalates exposure levels.
    Among 1305 boys who returned the questionnaire, 24.7% and 23.3% had pubic hair growth and breaking of voice. Among 1222 girls, 54.7% and 76.5% had pubic hair growth and breast growth, respectively. MnBP, MEOHP, MEHHP, MECPP were detected from all children and dominant metabolite was MECPP, followed by MnBP and MEHHP.
    Japan Society for the Promotion of Science, Grant-in-Aid for Young Scientists (B), Hokkaido University, 16K16200
  • Prepubertal exposure to short half-life chemicals and associations with their health outcomes
    Grants-in-Aid for Scientific Research
    2019 - 2019
    アイツバマイ ゆふ
    Japan Society for the Promotion of Science, Fund for the Promotion of Joint International Research (Fostering Joint International Research (A)), Hokkaido University, 19KK0288
  • Elucidation of molecular mechanism of ADHD based on a prospective birth cohort study
    Grants-in-Aid for Scientific Research Grant-in-Aid for Challenging Exploratory Research
    01 Apr. 2016 - 31 Mar. 2018
    Reiko kishi; AIT BAMAI Yu; KOBAYASHI Sumitaka
    We targeted DNA methylation as a mediator between prenatal exposure to environmental chemicals and attention-deficit/hyperactivity disorder (ADHD). We assessed methylation levels at 450K cytosine-guanine dinucleotide sites (CpGs) in cord blood DNA using an Illumina HumanMethylation 450 BeadChip, and examined association between methylation and prenatal exposure to perfluoroalkyl substances, phthalates, and bisphenol A. The epigenome-wide analyses (EWAS) showed significant differences in methylation associated with prenatal exposure.
    To investigate prospective association between DNA methylation at birth and ADHD-related behavior at 6 years, we extracted DNA from cord blood of ADHD groups (n=245) identified with ADHD rating scale (ADHD-RS) and control groups (n=317). Using a next-generation sequencer, we have quantified methylation levels at CpGs that showed significant association with prenatal exposure in the EWAS.
    Japan Society for the Promotion of Science, Grant-in-Aid for Challenging Exploratory Research, Hokkaido University, 16K15352
  • FLG variance and environmnetal chemical exposure to atopic dermatitis among school children
    Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)
    01 Apr. 2015 - 31 Mar. 2018
    Atsuko Araki; SHIMIZU Hiroshi; KOBAYASHI Sumitaka; MINATOYA Machiko; AIT BAMAI Yu; ITO Sachiko; TAKEUCHI Shinji; URAMARU Naoto; OKUDA Katsuhiro; TAKEDA Mai; KAWAI Toshio
    Association between environmental chemicals exposure on asthma and allergies and oxidative stress marker, 8-OHdG, and existence of FLG mutation were examined among 7 years old children. There was no difference on proportion of with or without FLG mutation between allergic cases and controls. When DINP levels in dust was higher, the risk of eczema increased, only those without FLG mutation. There was no significant association between FLG mutation, environmental chemicals and asthma and allergies, and 8-OHdG did not show any modifier effect on exposure and allergies. Studies of in vitro and in silico of DEHP and its 6 metabolites activation on PPARα/γ and PXR showed that DEHP and its metabolites have activities that differ from those of the parent compound. The results obtained from the microarray analysis suggest that DEHP and MEHP might affect the gene expression of THP-1 cells via PPARα and PXR.
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Hokkaido University, 15H04780
  • Phthalate exposure and its effects on onset of puberty
    Grants-in-Aid for Scientific Research Grant-in-Aid for Challenging Exploratory Research
    01 Apr. 2014 - 31 Mar. 2017
    Araki Atsuko; KISHI Reiko; AITBAMAI Yu
    Phthalates are ubiquitous environmental chemicals, which are widely used as plasticizes. Humans are exposed to phthalates since fetal life, and their endocrine disrupting properties has been concerned. However, prenatal exposure to phahalates and their effects on fetus onset of puberty in human are not well known. In this study, onset of puberty were examined among children registered to Sapporo cohort, the Hokkaido Study. Among those approached, 150 (45.6%) responded. Total effects of MEHP (primary metabolite of the most widely used phthalate, DEHP) levels in maternal blood was significantly positively associated with onset of puberty; natural log increase of MEHP (app. 2.67), onset of puberty delayed 7.17(95%CI:2.89-11.5)months among boys. Although progesterone and inhibin B were inversely associated with MEHP, none of hormones showed indirect effect of MEHP to onset of puberty. Girls did not show any association between MEHP, hormones, or onset of puberty.
    Japan Society for the Promotion of Science, Grant-in-Aid for Challenging Exploratory Research, Hokkaido University, 26670321
  • Environmental and Genetic risk factors of Atopic dermatitis among 7-year old children in birth cohort
    Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)
    01 Apr. 2012 - 31 Mar. 2015
    ARAKI Atsuko; NOMURA Toshifumi; KISHI Reiko; SHIMIZU Hiroshi; SASAKI Seiko; AIT BAMAI Yu; TAJIMA Shuji; UKAWA Shigekazu; CONG Shi
    The present study examined the risk of environmental factors such as mite allergens, phthalates, and organophosphate in house dust and filaggrin (FLG) gene variants on atopic dermatitis (AD) among 7 years old children who are participating in the Hokkaido study on Environment and Children's Health. About 10% of the participants in this study had FLG gene variants, which was consistent with other previous studies. The children with FLG gene variants significantly increased the risk of AD at 2 and 4 years of age, but were not at 7 years of age. Among 7 years old children with high levels of DiNP and without FLG gene variants significantly increased the risk of AD.
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Hokkaido University, 24390152