Chlorinated paraffins in indoor dust from Australia: Levels, congener patterns and preliminary assessment of human exposure

Chlorinated paraffins (CPs) are a group of polychlorinated n-alkanes with high production volumes. Until now. there are only limited data on the levels of CPs in the environment, especially in the indoor environment. In this study, dust samples were collected from 44 indoor environments, including 27 private houses, 10 offices, and 7 vehicles. Short-, medium-, and long-chain CPs were detected in all dust samples. The median concentration of Sigma CPs (C-10-C-21) was 57, 160 and 290 mu g/g, in houses, offices, and vehicles, respectively. Medium-chain CPs were the dominant group, on average accounting for 86% of Sigma CPs. Cl-6 and Cl-8 groups had the highest contributions to Sigma CPs across all the different microenvironments, while C-13 and C-14 were the predominant groups of SCCPs and MCCPs. Median exposure to Sigma CPs via indoor dust were estimated at 80 ng/kg/day and 620 mu g/kg/day for Australian adults and toddlers respectively. The daily intake of CPs via dust, in the worse scenario, was still 2-3 orders of magnitudes lower than the reference doses based on neoplastic effects. (C) 2019 Elsevier B.V. All rights reserved.