Dr. Kayo Ueda is Professor in Graduate School of Medicine in Hokkaido University, Japan. She started her working career as a clinician in the treatment of cardiovascular and respiratory diseases. After she changed her career as an environmental epidemiologist, she was engaged with studies clarifying the health effects of particulate air pollution and accumulated the evidence in Japan which contributed to environmental policy making. Currently, her works are to characterize human health risks from atmospheric environment including air pollutants and climate change in Asian countries as well as Japan. She has also been involved with multi-disciplinary research projects.
A systematic review was conducted to evaluate the effects of long-term exposure to particulate matter with diameters of less than 2.5 μm (PM2.5) on mortality. We searched PubMed for epidemiological studies investigating the association of long-term exposure to PM2.5 with mortality published between January 1990 and December 2015. We applied a random-effects model to calculate the combined effect estimates for PM2.5 mass. Twenty-four articles were identified (3 from Asia, 6 from Europe, and 15 from North America). It was common to assign the PM2.5 observations monitored at a fixed-site station to all residents in the corresponding area in the study published during 1990–2000. Recently, PM2.5 exposure assessment has utilized dispersion models, land use regression models, and satellite remote sensing. The mean or median concentration of PM2.5 for each study area varied from 8.1 to 35.3 μg/m3. The combined risk ratio was 1.07 (95% confidence interval: 1.04, 1.19) per 10 μg/m3 increase in the PM2.5 concentration. There was a significant heterogeneity. Further studies are needed in the area where the PM2.5 level is high.
Asian dust is a phenomenon involving the long-range transport of atmospheric pollutants originating from the desert areas of China and Mongolia. In recent years, the health effects of Asian dust have raised public concerns. Numerous studies on the health effects of Asian dust have been published since the last review in 2010. Thus, a literature review was conducted to shed light on the latest epidemiologic findings. PubMed and Science Direct databases were used for the review of epidemiologic studies published between June 2009 and April 2018. We identified 53 epidemiologic studies. Mortality, ambulance transportation, hospitalization/medical examination, changes in symptomatic, functional, and examination findings, as well as birth outcomes have been reported as outcomes. When the outcomes were categorized by disease, the effects of Asian dust on respiratory, cardiovascular, and allergic diseases raised concerns. The common evidences of causation between Asian dust and these diseases were the consistency of findings and temporal sequence of association. As results of research on dose-response relationships have become available, and the possibility that the health effects of Asian dust may vary depending on its chemical composition has been pointed out, further research using the exposure level indicators of Asian dust or its chemical composition should be conducted. Furthermore, with focus on the crucial issue of reducing exposure, research related to prevention and raising awareness should be further promoted.