Impacts of O₃ on premature mortality and crop yield loss across China

Exposure to ambient ozone (O₃) is a risk factor for public health and causes damage to vegetation, including agricultural crops. In this study, we performed a comprehensive estimate of the spatial distribution of premature deaths and main crop yield losses attributed to ambient O₃, across China in 2014, by applying the Global Burden of Diseases approach and AOT40 metric (i.e., above a threshold of O₃ concentration of 40 ppb). Our results show that China's total premature deaths in 2014 due to COPD attributed to O₃ exposure were 89,391 (CI95: 32,225–141,649) with spatial variation across provinces. O₃ induced production losses from all crops were 78.4 million metric tons, and the relative yield losses ranged from 8.5 to 14.0% for winter wheat, 3.9–15.0% for rice, and 2.2–5.5% for maize. The top four Chinese provinces (Sichuan, Shandong, Henan and Hunan) for premature deaths attributed to O₃ pollution also suffered severe losses in yields of winter wheat and rice. Our results provide quantitative evidence of O₃ induced impacts on both the public health and crop yields across Chinese provinces, which have important policy implications for the government to alleviate O₃ pollution in addition to PM_2.5 pollution that is currently being addressed.