Seasonal variations in atmospheric concentrations of organochlorine pesticides in urban and rural areas of Korea

Atmospheric concentrations of organochlorine pesticides (OCPs) were measured in both rural (Ansung) and urban (Seoul) areas in Korea from July, 1999 to May, 2000. The chemicals measured in this study include heptachlor, chlordanes, DDTs, hexachlorocyclohexanes (HCHs), and endosulfan. Endosulfan and α-HCH, with values of a few 100s to 1000s of pg m−3, were found to have higher concentrations than other compounds in both areas. Most OCPs showed higher concentrations in Ansung, with many potential sources, such as contaminated surfaces, relative to Seoul. The maximum and minimum concentrations of OCPs at both sites occurred in summer and winter, respectively. It can be partly explained by the variation of temperature. The correlation between atmospheric concentration and temperature was observed using Clausius–Clapeyron (CC) plots. The CC plots for most OCPs in both areas showed good linearity and steep slopes. It is hence inferred that their atmospheric concentrations might be mostly affected by re-volatilization from surfaces of local surroundings at the sampling sites.