Assessing dermal exposure to organochlorine pesticides in different populations of a prototypical agricultural city in South China

Persistent organic pollutants have been widely detected in the environment and pose a substantial threat to human health. However, few studies have directly investigated exposure to organochlorine pesticides (OCPs) through skin contact. Therefore, we aimed to evaluate dermal exposure to OCPs in different populations in a typical agricultural city in South China. Skin wipe samples were collected from the faces, hands, forearms, and shanks of 120 volunteers (50% male and 50% female) across various age groups. All ten target OCPs were detected in the samples, with concentrations ranging from non-detectable (ND) to 7200 ng/m². The concentration of OCPs displayed a consistent pattern of face > hand > forearm > shank regardless of age or sex. Daily average doses of dermal ingestion (DAD_derm) and hand-to-mouth contact ingestion (DAD_oral) ranged from ND to 68 ng/kg/d and from ND to 7.8 ng/kg/d, respectively. Hexachlorocyclohexane (HCH) was the primary contributor, accounting for 68% of the DAD_derm and 91% of the DAD_oral. No significant age- or sex-based differences were observed in DAD_derm, but DAD_oral showed significant variation, being markedly higher in preschoolers than in other age groups and higher in females than in males. Carcinogenic risks associated with OCPs dermal exposure ranged from ND to 2.4 × 10^{- 5}, with older adults facing the highest risk and females having significantly higher risk than males.