Distribution of organochlorine pesticides in atmospheric air of Tamilnadu, southern India

Passive air sampling was performed for urban, suburban, coastal, and agriculture air during April 2009–January 2010 in Tamilnadu, southern India, to know the distribution and fate of organochlorine pesticides (OCPs) residues. Exposed polyurethane foam samples (30 ± 2 days) were soxhlet extracted, and the extracts were analyzed using gas chromatography–mass spectrometric method. The total concentrations of 13 OCPs were in the range of not detected (ND)–41,400 pg/m3. Dichlorodiphenyltrichloroethane, dichlorodiphenyldichloroethylene, heptachlor, and mirex were found predominant during monsoon season. The elevated α/γ isomer ratio of hexachlorocyclohexane (HCH) (5.03) during summer revealed fresh/recent usage of HCH in coastal area. Dichlorodiphenyltrichloroethane ratio shows its fresh application in all the locations during monsoon season, which probably used to contain the diseases causing vectors. Detection of banned pesticides, such as aldrin, dieldrin, and heptachlor in air, indicating their illegal usage/or from old source. Furthermore, mirex, an unregistered pesticide in India, is being reported for the first time in air. More importantly, the obtained information will be used as a valuable baseline data for the management of atmospheric OCPs in future.