Ambient air pollution of particles and gas pollutants, and the predicted health risks from long-term exposure to PM 2.5 in Zhejiang province, China

Abstract

In recent years, ambient air has been severely contaminated by particulate matters (PMs) and some gas pollutants (nitrogen dioxide (NO₂) and sulfur dioxide (SO₂)) in China, and many studies have demonstrated that exposure to these pollutants can induce great adverse impacts on human health. The concentrations of the pollutants were much higher in winter than those in summer, and the average concentrations in this studied area were lower than those in northern China. In the comparison between high-resolution emission inventory and spatial distribution of PM_2.5, significant positive linear correlation was found. Though the pollutants had similar trends, NO₂ and SO₂ delayed with 1 h to PM_2.5. Besides, PM_2.5 had a lag time of 1 h to temperature and relative humidity. Significant linear correlation was found among pollutants and meteorological conditions, suggesting the impact of meteorological conditions on ambient air pollution other than emission. For the 24-h trend, lowest concentrations of PM_2.5, NO₂, and SO₂ were found around 15:00–18:00. In 2015, the population attributable fractions (PAFs) for ischemic heart disease (IHD), cerebrovascular disease (stroke), chronic obstructive pulmonary disease (COPD), lung cancer (LC), and acute lower respiratory infection (ALRI) due to the exposure to PM_2.5 in Zhejiang province were 25.82, 38.94, 17.73, 22.32, and 31.14%, respectively. The population-weighted mortality due to PM_2.5 exposure in Zhejiang province was lower than the average level of the whole country—China.