Characteristics and risk assessments of heavy metals in fine and coarse particles in an industrial area of central China

Abstract

In order to investigate the pollution level and chemical form transformation characteristics of heavy metals, atmospheric fine particles and coarse particles were collected in an urban industrial area of Zhuzhou City in central China during winter and summer. The results indicated that PM2.5 and PM10 all showed similar time variation, with the highest concentration in winter (112.1 μg/m3, 210.3 μg/m3) and the lowest concentration in summer (44.4 μg/m3, 81.0 μg/m3), respectively. As for heavy metals carried by atmospheric particles, only Cu had similar time variation with particle concentration and was mainly in oxidisable fraction. Zn, Pb and Cd were chiefly distributed in acid-extractable fraction, and Zhuzhou City was extremely polluted by these three heavy metals which mainly came from Qingshui Pond Industrial Area. Moreover, risk assessment results indicated that this area had high ecological risks on the environment and potential non-carcinogenic health effects and low carcinogenic risk to human health, especially for children. In addition, leaching test of atmospheric particles showed that the releasing of heavy metals in simulated acid rain primarily came from acid-extractable fraction, especially in winter, and the chemical form transformation followed a pattern of from stable state to unstable state after dissolving by acid rain.