Health effects associated with ozone in China: A systematic review

As the ozone (O₃) pollution becomes severe in China, it poses a threat to human health. Currently, studies on the impacts of O₃ on different regions and groups are limited. This review systematically summarizes the relationship between O₃ pollution and mortality and morbidity across the nation, regions, and cities in China, with a focus on the regional and group-specific studies. Then, we clarify the overall limitations in the research data, methods, and subjects. In addition, we briefly discuss the mechanisms by which O₃ exposure affects human health, analyzing the effects of O₃ on human health under heatwaves (temperature) condition, multi-pollutant modeling, and future climate scenarios. Finally, we give some suggestions for future research directions. Studies found that increased risks of premature mortality and morbidity of respiratory and cardiovascular diseases are closely associated with high concentration O₃ exposure. Besides, the old and children are sensitive groups, more studies are needed estimate the risk of their health associated with O₃ pollution. Severe O₃ pollution in Northern and Eastern China, has significantly increased premature mortality. O₃ pollution has led to decreased lung function in the elderly in East China, and a higher asthma risk among young people in South China. Comparing with other regions, less research studied the relationship between O₃ pollution and health of local people in Southwest, Central, Northeast, and Northwest Regions. Therefore, it is necessary to enhance research in these regions, with a particular emphasis on the distinctive health consequences of O₃ pollution in these regions. Given the diversity of regions and research groups, comprehensive comparison is crucial for determining the impact of O₃ pollution on human health in China.