Bioaccumulation and Health Risk Assessment of Heavy Metal (loid)s in Different Fish Species of Hainan Island, China

Fish contamination with heavy metal (loid)s could be a serious threat to human health. In this study, the concentrations of twelve heavy metal (loid)s in the liver, kidney, gills, muscles, skin and bones were determined in five different fishes, collected from the Hainan Island, China. Results indicated that the average concentrations of Fe, Cu, Zn, Cr, Mn, Se, Ni, As, Hg, Cd, Pb and Co in the fish tissues were 75.56, 6.935, 4.76, 4.05, 3.298, 0.981, 0.732, 0.643, 0.585, 0.263, 0.232, and 0.08 mg/kg respectively. Therefore, the hierarchical order of the metal concentrations in fishes observed was Fe > Cu > Zn > Cr > Mn > Se > Ni > As > Hg > Cd > Pb > Co. Findings of our study revealed that the average maximum concentrations of biologically essential heavy metals were found higher than those of biologically non-essential heavy metals. An average maximum Fe content was present in the kidneys of all fish, followed by liver, then gills. However, skin, muscles and bones which are not metabolically active sites for bioaccumulation contained low concentration. Significant positive and negative correlations were observed among the metal pairs. The THQ values for Cr, Cd, and As above 1 indicated a non-carcinogenic risk to human health. Integration of 12 heavy metal concentrations followed the order: metals in benthic fish > metals in demersal fish > metals in pelagic fish. Regular monitoring of the water and fish for heavy metals (loid)s should be done regularly to protect aquatic ecosystem and human health through targeted response measures.

Automated summary

This study found the presence of multiple heavy metals in fish from Hainan Island, China, with higher concentrations of essential heavy metals. Kidneys had the highest metal content, while skin, muscles, and bones had lower concentrations. Significant correlations were observed among the different metals, and levels of Cr, Cd, and As exceeded the threshold for non-carcinogenic risk to human health. Regular monitoring of water and fish is necessary to protect aquatic ecosystems and human health.