Source-specific health risk assessment of PM2.5 bound heavy metal in re-suspended fugitive dust: A case study in Wuhan metropolitan area, central China

Abstract

To more accurately assess the health risk of heavy metals (HMs) from PM2.5 re-suspended fugitive dust (RFD2.5), it is necessary to understand the main source of health risk from different types of RFD2.5. For this purpose, the HMs (As, Cd, Co, Cr, Mn, Ni, Pb, V, and Zn) in five types of RFD2.5 from the Wuhan metropolitan area, which was prepared with a homemade suspension chamber, were comprehensively measured. A method combining the positive matrix factorization with the health risk assessment model was used to quantify the source-specific health risks. Results indicate that traffic-related activities contributed the most HMs to RFD2.5 at 61.18%, followed by nature sources (21.58%), fossil fuels emission (9.32%), and local deposition (3.92%). Although the non-carcinogenic risk of HMs had not been found from RFD2.5 through inhaling, cancer risks from Cr exceed the safety threshold. Moreover, traffic-related activities were also the main reason to cause carcinogenic risk of Cr from RFD2.5 in the Wuhan metropolitan area, especially in Wuhan. Besides that, developing characteristics would affect the carcinogenic risk level from RFD2.5, such as citizens in high-speed economic development or tourist cities would face relative high carcinogenic risks of Cr from traffic-relate activities in RFD2.5, while in green economic transition or small-scale city such risks were shown as relatively low. The investigation improves the understanding of the source of HMs health risk in different types of RFD2.5 and the results provide valuable information on health risk mitigation strategies for environmental managers.