Dispersion of Short- and Medium-Chain Chlorinated Paraffins (CPs) from a CP Production Plant to the Surrounding Surface Soils and Coniferous Leaves.

Abstract

Chlorinated paraffin (CP) production is one important emission source for short- and medium-chain CPs (SCCPs and MCCPs) in the environment. In this study, 48 CP congener groups were measured in the surface soils and coniferous leaves collected from the inner and surrounding environment of a CP production plant that has been in operation for more than 30 years to investigate the dispersion and deposition behavior of SCCPs and MCCPs. The average concentrations of the sum of SCCPs and MCCPs in the in-plant coniferous leaves and surface soils were 4548.7 ng g-1 dry weight (dw) and 3481.8 ng g-1 dw, which were 2-fold and 10-fold higher than those in the surrounding environment, respectively. The Gaussian air pollution model explained the spatial distribution of CPs in the coniferous leaves, whereas the dispersion of CPs to the surrounding surface soils fits the Boltzmann equation well. Significant fractionation effect was observed for the atmospheric dispersion of CPs from the production plant. CP congener groups with higher octanol-air partitioning coefficients (KOA) were more predominant in the in-plant environment, whereas the ones with lower KOA values had the elevated proportion in the surrounding environment. A radius of approximately 4 km from the CP production plant was influenced by the atmospheric dispersion and deposition of CPs.