Pollution characteristics, sources, and risk assessment of heavy metals and perfluorinated compounds in PM2.5 in the major industrial city of northern Xinjiang, China

Abstract

At present, research on PM2.5 has focused on eastern and central China; little attention has been given to Xinjiang, the most northwestern part of China. Ten kinds of heavy metals (HMs) and 12 kinds of perfluorinated compounds (PFCs) in atmospheric PM2.5 are detected by inductively coupled plasma mass spectrometry and high-performance liquid chromatography-mass spectrometry, respectively. Principal component analysis and risk assessment methods are used to study HMs and PFCs and explore their pollution levels and health risks. Results show that HMs and PFCs are prevalent in atmospheric PM2.5 of Shihezi and Urumqi. The spatial distributions of HMs and PFCs in four sampling sites are development zone (B1) = industrial park (A1) > factory (A3) > school (A2) and A1 > A3 > B1 > A2, respectively. In the four sampling sites, copper, lead, zinc, and cadmium (Cd) contents are relatively high. Perfluorooctane sulfonate (PFOS), perfluorohexanoic acid (PFHxA), and perfluorooctanoic acid (PFOA) are the most prevalent PFCs. Risk assessment results show that PFCs in the atmosphere will not harm residents, but the Cd and nickel (Ni) in HMs are harmful to humans, especially Cd, which has both carcinogenic and non-carcinogenic risks. These findings indicate that the carcinogenic risk of HMs and PFCs in children is higher than in adults. In addition, HMs and PFCs may cause joint toxicity.