Source apportionment of PM2.5 and the impact of future PM2.5 changes on human health in the monsoon-influenced humid subtropical climate

Local emission sources and long-range transport of air pollutants are the main causes of PM2.5 pollution in developing metropolises. A modeling system was used to determine the main contributors of PM2.5 and future changes in PM2.5 concentrations in Hanoi, one of the fast-growing and most polluted capital cities in the world. Additionally, BenMAP was used to estimate the number of premature deaths caused or avoided due to PM2.5 concentration changes. October and December 2017 as well as April and June 2018 were selected for analysis. The source apportionment approach revealed that the boundary conditions (BCON), were the primary source of PM2.5, accounting for 24–59.7%. Agriculture was a substantial contributor of PM2.5 within Hanoi in June and October, accounting for 27.8 and 18.8%, respectively. Projected emissions for 2030 from our previous work, which were estimated based on the action plans and scenarios proposed by the government, were used as input into the air quality modeling system to analyze changes in the concentrations of the total PM2.5 and its major components owing to emissions changes. It is shown that, the concentrations of PM2.5 can increase by 0.5 and 1.6 μg/m3 in April and December, and decrease by 3.2 and 1.5 μg/m3 in June and October, respectively. Using BenMAP , it is estimated that these changes can cause 45 and 95 premature deaths in April and December, but prevent 198 and 88 premature deaths in June and October respectively, in Hanoi.