Exposure and health risk assessment of PM2.5-bound trace metals during winter in university campus in Northeast China

Abstract

In order to better understand the risk to students' health caused by pollution derived from fine particulate matter with an aerodynamic diameter <2.5mm (PM_2.5), this study collected 189 samples in one outdoor and four different functional indoor environments of a research center in a university campus. Trace metals (TMs) bound to PM_2.5 in outdoor and indoor environments were measured using X-ray fluorescence spectrometry. The TMs measured were: As, Co, Cd, Cr, Ni, Cu, Zn, Mn, Hg, and Pb. The measurements of PM_2.5-bound TMs before and during the 2015 Spring Festival held in Northeast China were compared. Results showed that pollution due to PM_2.5-bound TMs in outdoor and indoor environments was higher before than during the Spring Festival. Cu (in three indoor environments) and Zn (in an outdoor environment) showed the highest concentrations among the ten TMs that were measured. Hg showed the lowest concentrations in all the environments analyzed. The concentrations of PM_2.5-bound TMs declined among four indoor environments in the following order: the atrium, the students' office (sampled just nine days before the Spring Festival), the laboratory, and an empty room. The potential carcinogenic and non-carcinogenic health risks derived from PM_2.5-bound TMs were within safe limits for graduate and undergraduate students, according to the standards established by the United States Environmental Protection Agency (USEPA).