Residue Level, Spatial Distribution and Source of Organochlorine Pesticides in Atmospheric PM₂₅ in Jiangyin City

Atmospheric PM_2.5 samples were collected in different functional areas of Jiangyin, Jiangsu Province with high volume sampler in the autumn of 2013, for analysis of concentrations of 19 kinds of organochlorine pesticides (OCPs) with GC-MS in an attempt to determine residue level, spatial distribution and source of the pollutants. Results show that the mean total concentration of ∑OCPs in PM_2.5 was 2.84 ng·m^-3. Among the 19 kinds of OCPs, HCHs, DDTs, chlordanes and methoxychlor were the dominant ones in the PM_2.5, accounting for 48.2%, 19.7%, 12.3% and 12.5%, respectively. Compared with the atmospheres in other regions either domestic or abroad, the one in Jiangyin was moderate by the upper side in OCPs pollution level. The OCPs spatial distribution tendency map shows that the pollution level is the highest in the Environmental Monitoring Center, and the lowest in the Shengang Park. Source analysis reveals that DDTs and chlordane in the PM_2.5 came from historical residue pollution, while HCHs did from both historical residue of industrial HCHs and recent input of large volumes of lindane.