Occurrence, bioaccumulation and risk assessment of dioxin-like PCBs along the Chenab river, Pakistan

This study aimed to assess the occurrence, distribution and dietary risks of seven dl-PCBs (dioxin-like PCBs) in eleven collected fish species from Chenab river, Pakistan. ∑7dl-PCBs (ng g(-1), wet weight) burden was species-specific and the maximum average concentrations were found in Mastacembelus armatus (5.43), and Rita rita (5.1). Correlation of each dl-PCBs with δ(15)N%, indicated a food chain accumulation process of these chemicals into Chenab river, Pakistan. Species-specific toxicity of each dl-PCBs (WHO-PCBs TEQ) was calculated and higher values were found in three carnivore fish species i.e., M. armatus (2.5 pg TEQ g(-1)), R. rita (2.47 pg TEQ g(-1)), Securicola gora (2.98 pg TEQ g(-1)) and herbivore fish species i.e., Cirrhinus mrigala (2.44 pg TEQ g(-1)). The EDI (Estimated Daily Intake) values in most cases exceeded the WHO benchmark (4 pg WHO-TEQ kg(-1) bw d(-1)) evidencing a potential health risk for consumers via fish consumption from Chenab river.