[Health Impacts of Air Pollution in Tianjin]

Ambient air pollution is a dominant determinant of health. The health effects and economic losses due to air pollution are very important for decision-making. Since the implementation of the "Air Pollution Prevention and Control Action Plan" and "blue sky defense war" policies, the air quality of Tianjin has changed significantly. Here, the health effects and economic losses attributable to ambient air pollution in Tianjin from 2013 to 2020 wereestimated. For the particulate matter which has complex components, we assessed the inhalation health risks of heavy metals and polycyclic aromatic hydrocarbons (PAHs) in PM_2.5. The variation in the concentration of the main components of PM_2.5 was also analyzed. The results showed that improved air quality had positive health benefits. The health benefits from SO₂ were the highest among the six air pollutants, and 3786 deaths were avoided in 2020 compared to in 2013 due to lower SO₂ concentration. The economic losses caused by air pollutants ranged from several billion to ten billion yuan. Among the six air pollutants, particulate matter and ozone had higher health losses in recent years. The health risks of heavy metals and PAHs in PM_2.5 showed a decreasing trend. However, Cr(Ⅵ), As, Cd, and Ni in PM_2.5in the winter of 2020 still had respiratorysystem carcinogenic risk, whereas there was no health risk of PAHs in PM_2.5in 2019-2020. The concentrations of main components of PM_2.5 have decreased significantly. In the future, the reduction of health loss caused by air pollution depends on synergy governance of particulate matter and ozone and further research on health effects.