Assessing NO2-related health effects by non-linear and linear methods on a national level

Abstract

Exposure to NO2 pollution has a significant adverse effect on residents' health. However, few studies have assessed the health effects associated with NO2 pollution. Compared with PM2.5 pollution, the harmfulness of NO2 pollution has not been quantitatively studied or clearly identified. In this study, we assessed the NO2 exposure-related health effects by non-linear and linear methods, taking advantage of online monitoring and survey data. We also assessed the economic cost of NO2 pollution in 338 cities in China. Our results showed that the average annual concentration of NO2 in the top fifteen cities with more than ten million permanent residents (except for Shenzhen, in the Guangdong province) exceeded the annual Grade II standards (40 μg/m3). The estimated national NO2-related all-cause mortality for non-linear and linear methods were 388.5 × 103 (95% CI: 198.1 × 103–748.2 × 103) and 374.1 × 103 (95% CI: 194.3 × 103–695.9 × 103), respectively. The total calculated national economic cost was about 28.8 billion US$ (95% CI: 14.7–55.4) in 2016. In addition, the comparison results showed that the harm caused by PM2.5 pollution was about four times that of NO2 pollution. Our statistics contribute to the limited research on NO2 pollution's effects on health and the economy in China.