Assessing Trace Elements Bioaccumulation in Coastal River Fish and Shellfish: Implications for Human Health and Risk Evaluation.

Abstract

The presence of heavy metal contaminants in fish and shellfish in aquatic environments poses a risk to human health due to trophic transfer. This study determined the levels of various trace elements (Fe, As, Cr, Zn, Cu, Ni, Pb, and Cd) in the muscles, gills, and liver of hilsa (Tenualosa ilisha) and prawn (Macrobrachium rosenbergii) samples obtained from the Tetulia River, Bangladesh. The results showed that the level of trace elements in different body parts differed significantly (P < 0.05) between species, displayed below recommended threshold levels. The cumulative low to higher hierarchic concentration of the trace elements was as follows: Fe > Zn > Cu > Cr > Ni > Pb > As > Cd. Hilsa had significantly (P < 0.05) higher bioaccumulated trace elements compared to prawn. With the exception of Ni and Cd, the estimated daily intakes (EDI) for both adults and children were below the recommended daily allowance (RDA), which exhibits that other trace elements do not cause harm to human health. Furthermore, the hazard index (HI) and total hazard quotient (THQ) were also found to be within acceptable limits, taking into account the higher vulnerability of children to toxicity compared to adults. Notably, the HI suggested that children were approximately four times more susceptible to both carcinogenic and non-carcinogenic effects compared to adults. Ultimately, the levels of carcinogenic risk were deemed acceptable, despite the estimated values suggesting susceptibility to adverse effects in both adults and children. This study concluded that fish and shellfish may not pose a health risk to consumers, highlighting the importance of further monitoring of trace elements in the catchment area.