The concentrations of organochlorine pesticides (OCPs) and polybrominated diphenyl ethers (PBDEs) were evaluated in snails from different locations in the Niger Delta of Nigeria to provide data about their sources and possible risk to humans from the consumption of snails. The OCP and PBDE concentrations in snail samples ranged from 0.31 to 12.2 ng g-1 and 0.21 to 10.9 ng g-1, respectively. The distribution patterns indicated the dominance of chlordanes and penta-BDEs for OCPs and PBDEs, respectively. The hazard index and total cancer risk values for human exposure to OCPs and PBDEs through consumption of these snails were less than 1 and 10-6 (acceptable risk value), respectively, indicating unlikely adverse health effects. The isomer ratios of OCPs in these snails reflected both historical and recent contamination, while the distribution patterns of PBDEs in these snails indicated sources linked to the use of the penta-BDE and octa-BDE formulations rather than the deca-BDE mixture in this region.
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