Bioaccumulation variability and human health risk assessment of organochlorine pesticides in edible fish and shellfish from the Northeast Bay of Bengal

This study investigates the accumulation of organochlorine pesticides (OCPs) in edible fish and shellfish species from the northeast Bay of Bengal, emphasizing species variability, potential contamination sources, and associated human health risks. Samples of three finfish species (Tenualosa ilisha, Pampus argenteus, and Harpadon nehereus) and two shellfish species (Penaeus indicus and Scylla serrata) were collected from Cox's Bazar and Chattogram, key fishing zones in the Bay of Bengal coast of Bangladesh. Sixteen OCP compounds, including DDTs (p,p′-DDT, o,p′-DDT, p,p′-DDE, o,p′-DDE, p,p′-DDD and o,p′-DDD), Hexachlorocyclohexanes (HCHs; α-HCH, β-HCH, γ-HCH and δ-HCH), Heptachlors (HPTs; heptachlor, cis- and trans-heptachlor epoxide), DRNs (Aldrin, Dieldrin and Endrine) were analyzed using gas chromatography-tandem mass spectrometry (GC–MS/MS), with total concentrations ranging from 19.28 ± 9.56 to 246.77 ± 113.02 ng g⁻¹ wet weight. Samples exhibited significantly higher concentrations in Chattogram due to increased industrial activities. Results showed that DDTs were the predominant OCPs, followed by HCHs. Risk assessment indicated that the estimated daily intake of OCPs was below acceptable thresholds, suggesting no immediate risk; however, the levels of aldrin (S. serrata, 1.89E-04), dieldrin (T. ilisha, 1.90E-04; S. serrata, 2.72E-04), and heptachlor exceeded carcinogenic risk thresholds, raising long-term health concerns. Variability in contamination levels was influenced by species-specific lipid content and habitat, with S. serrata (246.77 ± 113.02 ng g⁻¹) and T. ilisha (153.75 ± 50.84 ng g⁻¹) showing the highest OCP concentrations. The findings highlight the need for strict regulatory measures, regular monitoring, and public awareness to mitigate risks and promote seafood safety practices in the region.