Human dermal exposure to short- and medium-chain chlorinated paraffins: Effect of populations, activities, gender, and haze pollution

Abstract

Human dermal exposure to chlorinated paraffins (CPs) has not been well documented. Therefore, hand wipes were collected from four occupational populations to analyze short-chain CPs (SCCPs) and medium-chain CPs (MCCPs) in order to estimate dermal uptake and oral ingestion via hand-to-mouth contact. The total CP levels (∑SCCPs and ∑MCCPs) in wipes ranged from 71.4 to 2310µg/m2 in security guards, 37.6 to 333µg/m2 in taxi drivers, 20.8 to 559µg/m2 in office workers, and 20.9 to 932µg/m2 in undergraduates, respectively. Security guards exhibited the highest levels of ∑SCCPs among four populations (p < 0.01). In undergraduates engaged in outdoor activities, C13 emerged as the most dominant SCCPs homologue group, followed by C12, C11, and C10. The levels of ∑SCCPs and ∑MCCPs in males in light haze pollution were significantly higher than that in heavy haze pollution (p < 0.05). The median estimated dermal absorption dose of SCCPs and MCCPs via hand was 22.2 and 104ng (kg of bw)-1 day-1, respectively, approximately 1.5 times the oral ingestion [12.3 and 74.4ng (kg of bw)-1 day-1], suggesting that hand contact is a significant exposure source to humans. Environmental ImplicationSCCPs and MCCPs may pose potential risks to human health through dermal absorption and oral ingestion via hand-to-mouth contact. However, their pollution characteristics and associated health risks posed in occupational populations have largely been overlooked. To address health risks of SCCPs and MCCPs, this study investigated their abundance and human dermal exposure among four occupational populations, considering the effects of outdoor activities, gender, and haze pollution using handwipe methods. Our findings raise concerns about SCCPs and MCCPs pollution among occupational populations and provide practical insights into their dermal exposure.