Occurrence, quantities and probable human health risks of indicatory polychlorinated biphenyls in processed Lates niloticus (L.) products from Lake Victoria in Tanzania

Abstract

A study was conducted in Lake Victoria to assess the occurrence, levels and risks of indicator polychlorinated biphenyls (PCBs) in four processed Lates niloticus (L.) products (salted-sundried, trims, smoked and deep-fried). Samples extractions were done using QuEChERS method while detection and quantification of congeners was done using a GC- ECD and GC- MS. Six PCBs (CB 28, CB 52, CB 118, CB 138, CB 153 and CB 180) were detected at measurable quantities in fish products. The PCBs; CB 138, CB 153 and CB 180 dominated the loading due to their structures and high degree of chlorination. However, the mean concentration of PCBs in this study were below MRL of 75 micro g/kg set for fish by European Commission, implying that the fish products were safe for human consumption in regard to indicator PCBs. Similarly, indicator PCBs, CB 138, CB 153 and CB 180 were more prevalent (20 to 80%) in all fish products than other congeners. For both adults and children the cancer risks were low-to-moderate (ranging from 2.0E-04 to 3.0E-04 for adults and 2.0E-04 to 1.0E-03 for children) while the non-cancer risks were insignificant as the Hazard Indices were less than one.