Effects of short- and long-term exposures to multiple air pollutants on depression among the labor force: A nationwide longitudinal study in China.

BACKGROUND: Depression prevalence had surged within the labor force population in recent years. While a link between air pollution and depression was evident, there was a notable scarcity of research focusing on the workforce.

METHODS: This nationwide longitudinal study analyzed 27,457 workers aged 15-64. We estimated monthly mean concentrations of fine particulate matter (PM2.5 ), its primary components, and Ozone (O3 ) at participants' residences using spatiotemporal models. To assess the relationship between short- (1 to 3 months) and long-term (1 to 2 years) exposure to various air pollutants and depressive symptoms and occurrences, we employed linear mixed effects models and mixed effects logistic regression. We considered potential occupational moderators, such as employment relationship, labor contracts, overtime compensation, and total annual income.

RESULTS: We found significant increases in depression risks within the workforce linked to both short- and long-term air pollution exposure. A 10 μg/m3 rise in 2-year average PM2.5 , black carbon (BC), and O3 concentrations correlated with increments in depressive scores of 0.009, 0.173, and 0.010, and a higher likelihood of depression prevalence by 0.5 %, 12.6 %, and 0.7 %. The impacts of air pollutants and depression were more prominent in people without labor contracts, overtime compensation, and lower total incomes.

CONCLUSION: Exposures to air pollutants could increase the risk of depression in labor force population. The mitigating effects of higher income, benefits, and job security against depression underscore the need for focused mental health interventions.