Distribution, congener profile, and risk of polybrominated diphenyl ethers and dechlorane plus in water and sediment from two tributaries of the Chenab River, Pakistan.

There are a limited number of scientific reports available regarding polybrominated diphenyl ethers (PBDEs) and dechlorane plus (DP) screening levels and ecological risk assessment in environmental compartments. The present study was aimed to assess the screening-level risk assessment, congener-specific analysis, and spatial distribution pattern of PBDEs and DP in water and sediment. Samples were collected from upstream feeding tributaries (Nullah Aik and Nullah Palkhu) of the River Chenab, Pakistan. ∑PBDE concentrations in water and sediment ranged from 0.48 to 73.4 ng L(-1) and 0.35 to 88.1 ng g(-1) (dw), respectively, whereas levels of ∑DP in water and sediment were 0.01-4.58 and 0.10-12.5 ng g(-1) dw, respectively. Ratio for fsyn in sediment (ng g(-1)) and water (ng L(-1)) ranged between 0.59-0.64 and 0.60-0.68, respectively, which reflected no use of industrial mixture of DP isomers in the study area. Potential risks to ecological integrities through contaminated water and sediments in the study area were deemed marginal at the present time as assessed on the basis of the available and current toxicological data. The scarcity of data on levels, source apportionment, and detected permissible limits of PBDEs and DP warrant future auxiliary study of this group of contaminants.