Dechlorane Plus in air, dust, hand wipes, and hair at a typical e-waste site in South China: implications for human exposure

Abstract

Dechlorane Plus (DP) is a widely used flame retardant in various electronic devices. E-waste (EW) dismantling workers could be widely exposed to DP, but related studies are still limited. Therefore, we conducted an extensive study on the levels of DP and its dechlorinated derivatives (anti-Cl₁₁-DP and Cl₁₀-DP) in various environmental and human samples from a typical e-waste dismantling site located in China. Paired hair, hand wipe, indoor air, and indoor dust samples were collected from EW workers, non-EW workers and nearby residents. Hair was divided into an external fraction (hair-Ex) from surface washing and an internal fraction (hair-In) from digested washed hair. Our findings indicated that the DP concentrations in air and dust samples varied between 7.44 and 6200 pg m⁻³ and 0.355 and 7000 ng g⁻¹, respectively. The DP concentrations in hair-internal, hair-external, and hand wipe samples varied between 0.896 and 39.9 ng g⁻¹, 0.954 and 66.1 ng g⁻¹, and 1.25 and 1080 ng g⁻¹, respectively. The fractional abundance of anti-DP (f_anti) in hair-internal samples was significantly lower than in other samples (P < 0.05). Concentrations of anti-Cl₁₁-DP in both internal and external hair samples collected from EW recycling workers demonstrated statistically significant reductions relative to adult non-occupationally exposed individuals. This disparity may arise from the restricted metabolic clearance capacity of anti-Cl₁₁-DP in human physiological systems. The median proportion of anti-Cl₁₁-DP relative to ∑DPs was significantly elevated in hair-internal samples compared to both indoor dust samples (P < 0.05) and hair-external samples (P < 0.05), indicating a substantial enrichment of anti-Cl₁₁-DP in humans.