Organochlorine pesticides (OCPs) in air-conditioner filter dust of indoor urban setting: Implication for health risk in a developing country

This preliminary investigation highlights the occurrence of organochlorine pesticides (OCPs) in the indoor environment of a megacity, Lahore, Pakistan using the dust ensnared by air-conditioner filters. The sigma(16)OCPs concentration ranged from 7.53 to 1272.87 ng/g with the highest percent contribution by sigma DDT (dichlorodiphenyltrichloroethane; 87.21%) and aldrin (6.58%). The spatial variation of OCPs profile revealed relatively higher concentration from homes near to agricultural and abandoned DDT manufacturing sites. Calculated isomer ratios revealed historic sources of hexachlorocyclohexanes (HCHs) and the fresh input of technical DDT and chlordane by the dwellers. The air conditioner dust was helpful to better understand the health risk in the indoor environment. So far a high lifetime cancer risk (10(-3)) was predicted for toddlers via accidental ingestion, inhalation, and dermal exposure. Similarly, the non-carcinogenic risk-based hazard quotient was found to be high for toddlers (6.94) and within the permissible limit (<1) for adults.