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Introduction Asian dust is a seasonal meteorological phenomenon caused by dust storms that originate in the deserts of Mongolia and northern China and are carried eastward along mid-latitude westerlies to [...], BACKGROUND: Potential adverse health effects of Asian dust exposure have been reported, but systematic reviews and quantitative syntheses are lacking. OBJECTIVE: We reviewed epidemiologic studies that assessed the risk of mortality, hospital admissions, and symptoms/dysfunction associated with exposure to Asian dust. METHODS: We performed a systematic search of PubMed and Web of Science to identify studies that reported the association between Asian dust exposure and human health outcomes. We conducted separate meta-analyses using a random-effects model for mortality and hospital admissions for a specific health outcome and assessed pooled estimates for each lag when at least three studies were available for a specific lag. RESULTS: We identified 89 studies that met our inclusion criteria for the systematic review, and 21 studies were included in the meta-analysis. The pooled estimates (percentage changes) of mortality from circulatory and respiratory causes for Asian dust days vs. non- Asian dust days were 2.33% [95% confidence interval (CI): 0.76, 3.93] increase at lag 0 and 3.99% (95% CI: 0.08, 8.06) increase at lag 3, respectively. The increased risk for hospital admissions for respiratory disease, asthma, and pneumonia peaked at lag 3 by 8.85% (95% CI: 0.80, 17.55), 14.55% (95% CI: 6.74, 22.94), and 8.51% (95% CI: 2.89, 14.44), respectively. Seven of 12 studies reported reduced peak expiratory flow, and 16 of 21 studies reported increased respiratory symptoms associated with Asian dust exposure. There were substantial variations between the studies in definitions of Asian dust, study designs, model specifications, and confounder controls. DISCUSSION: We found evidence of increased mortality and hospital admissions for circulatory and respiratory events. However, the number of studies included in the meta-analysis was not large and further evidences are merited to strengthen our conclusions. Standardized protocols for epidemiological studies would facilitate interstudy comparisons. https://doi.org/10.1289/EHP5312

Introduction Time series data on daily air pollution concentrations, weather conditions, and daily measures of health outcomes (e.g., mortality, hospital admissions), have been used to assess how environmental factors may [...], BACKGROUND: The evidence and method are limited for the associations between mortality and temperature variability (TV) within or between days. OBJECTIVES: We developed a novel method to calculate TV and investigated TV-mortality associations using a large multicountry data set. METHODS: We collected daily data for temperature and mortality from 372 locations in 12 countries/regions (Australia, Brazil, Canada, China, Japan, Moldova, South Korea, Spain, Taiwan, Thailand, the United Kingdom, and the United States). We calculated TV from the standard deviation of the minimum and maximum temperatures during the exposure days. Two-stage analyses were used to assess the relationship between TV and mortality. In the first stage, a Poisson regression model allowing over-dispersion was used to estimate the community-specific TV-mortality relationship, after controlling for potential confounders. In the second stage, a meta-analysis was used to pool the effect estimates within each country. RESULTS: There was a significant association between TV and mortality in all countries, even after controlling for the effects of daily mean temperature. In stratified analyses, TV was still significantly associated with mortality in cold, hot, and moderate seasons. Mortality risks related to TV were higher in hot areas than in cold areas when using short TV exposures (0-1 days), whereas TV-related mortality risks were higher in moderate areas than in cold and hot areas when using longer TV exposures (0-7 days). CONCLUSIONS: The results indicate that more attention should be paid to unstable weather conditions in order to protect health. These findings may have implications for developing public health policies to manage health risks of climate change. http://dx.doi.org/10.1289/EHP149

Introduction Suicide is a crucial public health concern. In East Asia (a sub-region of Asia), suicide rates in South Korea, Japan, and Taiwan have increased to high levels. Suicide rates [...], BACKGROUND: A limited number of studies suggest that ambient temperature contributes to suicide; these studies typically focus on a single nation and use temporally and spatially aggregated data. OBJECTIVE: We evaluated the association between ambient temperature and suicide in multiple cities in three East Asian countries. METHODS: A time-stratified case-crossover method was used to explore the relationship between temperature and suicide, adjusting for potential time-varying confounders and time-invariant individual characteristics. Sex- and age-specific associations of temperature with suicide were estimated, as were interactions between temperature and these variables. A random-effects meta-analysis was used to estimate country-specific pooled associations of temperature with suicide. RESULTS: An increase in temperature corresponding to half of the city-specific standard deviation was positively associated with suicide in most cities, although average suicide rates varied substantially. Pooled country-level effect estimates were 7.8% (95% CI: 5.0, 10.8%) for a 2.3°C increase in ambient temperature in Taiwan, 6.8% (95% CI: 5.4, 8.2%) for a 4.7°C increase in Korea, and 4.5% (95% CI: 3.3, 5.7%) for a 4.2°C increase in Japan. The association between temperature and suicide was significant even after adjusting for sunshine duration; the association between sunshine and suicide was not significant. The associations were greater among men than women in 12 of the 15 cities although not significantly so. There was little evidence of a consistent pattern of associations with age. In general, associations were strongest with temperature on the same day or the previous day, with little evidence of associations with temperature over longer lags (up to 5 days). CONCLUSIONS: We estimated consistent positive associations between suicide and elevated ambient temperature in three East Asian countries, regardless of country, sex, and age.

Introduction Suicide is a significant public health concern. An estimated 804,000 people worldwide died by suicide in 2012, accounting for 1.4% of all deaths; suicide constitutes the 15th most common [...], Background: There is growing evidence suggesting an association between air pollution and suicide. However, previous findings varied depending on the type of air pollutant and study location. Objectives: We examined the association between air pollutants and suicide in 10 large cities in South Korea, Japan, and Taiwan. Methods: We used a two-stage meta-analysis. First, we conducted a time- stratified case-crossover analysis to estimate the short-term association between nitrogen dioxide (N[O.sub.2]), sulfur dioxide (S[O.sub.2]), and particulate matter [aerodynamic diameter [less than or equal to] 10 [micro]m (P[M.sub.10]), aerodynamic diameter [less than or equal to] 2.5 [micro]m (P[M.sub.2.5]), and P[M.sub.10-2.5]] and suicide, adjusted for weather factors, day-of-week, long-term time trends, and season. Then, we conducted a meta-analysis to combine the city-specific effect estimates for N[O.sub.2], S[O.sub.2], and P[M.sub.10] across 10 cities and for P[M.sub.2.5] and P[M.sub.10-2.5] across 3 cities. We first fitted single-pollutant models, followed by two-pollutant models to examine the robustness of the associations. Results: Higher risk of suicide was associated with higher levels of N[O.sub.2], S[O.sub.2], P[M.sub.10], and P[M.sub.10-2.5] over multiple days. The combined relative risks (RRs) were 1.019 for N[O.sub.2] (95% confidence interval [CI]: 0.999, 1.039), 1.020 for S[O.sub.2] (95% CI: 1.005, 1.036), 1.016 for P[M.sub.10] (95% CI: 1.004, 1.029), and 1.019 for P[M.sub.10-2.5] (95% CI: 1.005, 1.033) per interquartile range (IQR) increase in the 0-1 d average level of each pollutant. We found no evidence of an association for P[M.sub.2.5]. Some of the associations, particularly for S[O.sub.2] and N[O.sub.2], were attenuated after adjusting for a second pollutant. Conclusions: Our findings suggest that higher levels of air pollution may be associated with suicide, and further research is merited to understand the underlying mechanisms. https://doi.org/10.1289/EHP2223