Assessment of human health risks associated with heavy metals accumulation in the freshwater fish Pangasianodon hypophthalmus in Bangladesh

Abstract

In this study, pangas and feed samples were analyzed to estimate the levels of metallic elements and to profile the human health risks due to consumption of contaminated fish. This investigation confirmed significant variations in heavy metal concentrations among different tissues of pangas in the order of Ni> Cu> Pb> Cd> Cr in pre-monsoon; and Ni> Cd= Cu> Pb= Cr in post-monsoon. Considerably higher concentrations of Pb, Cu and Cr were estimated in liver; and Cd and Ni were detected in muscle than other organs (p>0.05). Statistically significant higher amount of Cd, Ni, and Cu were observed in pre-monsoon than post-monsoon. Furthermore, three metal pairs showed significant association (Pb-Ni and Pb-Cu involved positively; Cd-Ni acted negatively). In pre-monsoon, Cd, Pb, Ni, Cu concentrations of feed significantly differed than pangas contents; whereas only Cu varied during the post-monsoon. Regression analysis revealed the significant effect of Ni content in feed on the Cu deposition of pangas (p-value 0.027, that was <0.05). For the assessment of potential human health risk of the studied metals, estimated daily intake (EDI), target hazard quotient (THQ), hazard index (HI) and carcinogenic risk (CR) indices were calculated. Studied EDI indicated that an average adult ingested a higher amount of Ni and Cu than the recommended intake limit. Nevertheless, only the higher EDI of Ni increases the value of THQ and HI than standard limit indicates adverse non-carcinogenic risk. However, lower CR of Pb confirmed no serious health hazard due to the ingestion of pangas. Factor analysis through principal component and cluster analysis suggested that higher concentrations of Pb and Ni may regulate by the feed used, geochemical properties or rapid industrialization in the study area. A proper monitoring for controlling the quality of fish feed with sustainable planning for industrialization could secure the booming of pangasius aquaculture in Bangladesh.