Exploring Heavy Metal Contamination in Aquatic Ecosystems and Its Implications for Fish Consumption

Abstract

Research explores the contamination of aquatic ecosystems by various heavy metals and the potential health risks to humans from consuming fish. Twelve heavy metalloids were found in 200 samples of both wild and farmed fish species, including arsenic (As), cadmium (Cd), lead (Pb), mercury (Hg), nickel (Ni), copper (Cu), zinc (Zn), chromium (Cr), manganese (Mn), iron (Fe), aluminum (Al), and cobalt (Co). Several metals exceeded safe intake standards, and the research showed that contamination levels varied among species. Specifically, some fish species had greater concentrations of Hg and Pb, whereas the ones that lived in deeper, stagnant waters exhibited notable accumulations of Mn, Fe, and Co. The bioaccumulation of these contaminants might be facilitated by artificial feeding techniques and limited water conditions, as evidenced by the significant link between sediment pollution and metal accumulation in farmed fish. Because of the varied habitats and feeding habits, wild fish showed more varied contamination patterns. Although the majority of metals' target hazard quotients (THQs) were below acceptable bounds, several fish species showed higher Pb and Cd concentrations, which might be harmful to long-term health. A low risk of cancer was indicated by the carcinogenic risk indices for Ni, As, and Co getting below the safety threshold of 10⁻⁴. The research underscores the need to monitor species with higher bioaccumulation susceptibility and reduce metal contamination in aquaculture. It emphasizes the need for further research on chronic heavy metal exposure, biological and environmental factors, and health implications