Human Health Risks Surveillance of Polychlorinated Biphenyls in Bovine Milk from Alluvial Plain of Punjab, Pakistan

Abstract Punjab is the leading province of Pakistan in the production of bovine milk and its consumption. Rapid industrialization, high energy demand and production of waste have increased the risk of PCB toxicity in the environment. This research work was designed to assess human dietary exposure of polychlorinated biphenyls (∑PCBs 17 congeners) through ingestion of buffalo and cow’s milk from eight main districts of Punjab, Pakistan. The average concentration of ∑DL-PCBs in buffalo and cow milk samples were analyzed (8.74 ng g-1 and 14.60 ng g-1) and ∑I-PCBs (11.54 ng g-1 and 18.68 ng g-1) respectively. The PCB-156 was predominantly high congener found in both buffalo (2.84 ng g-1) and cow milk (2.86 ng g-1). It was found that the highest PCBs in bovine milk samples were observed in close vicinities of urban and industrial areas. The estimated daily consumptions of DL-PCBs and I-PCBs, from buffalo and cow milk, were below the acceptable daily intake for both adults and children. Moreover, Hazard Quotients (HQ) of ∑PCBs17 congeners value were less than 1.0 in adults and greater in the case of children reflecting the high chances of cancer risk. Furthermore, comprehensive monitoring for childhood cancer is recommended to establish the relationship in future studies.