Sustainable Approaches to Heavy Metal Remediation in Aquatic Systems: Challenges and Innovations

The heavy metals released into aquatic ecosystems from industrial waste sites are both persistent and toxic and have the potential to accumulate in food webs up to humans, which could lead to serious environmental problems as well as human health hazards. The objective of this review is to critically evaluate the sources, speciation, environmental behavior, and toxicological impacts of heavy metals in aquatic ecosystems, with a focus on their bioavailability, bioaccumulation, and associated health risks. In this review, we present a review that discuss multidisciplinary literature on heavy metal pollution of water systems, combining the knowledge across environmental sciences, toxicology and public health studies. The main metals were categorized according to their sources and pathways as follows: natural and anthropogenic routes, were used in the quantitative risk assessment integrated with available physicochemical and toxicological properties. Environmental behavior and toxicology profiles of heavy metals are wide-ranging. High degree of bioaccumulation potential and long-term persistence were found in quantities of cadmium, mercury and chromium. Although very essential, zinc and copper can be toxic at high concentrations. These pollutants get concentrated in the tissue of aquatic organisms, where it continues to bioaccumulate and biomagnified throughout the food web, thereby affecting a broad range of other animals over extended periods. These approaches like membrane filtration, biosorption, phytoremediation and nanotechnology are promising in conjunction with pollution indices coupled with risk assessment models. The complex relationship between heavy metal speciation, environmental factors and biological uptake illustrates the difficulty of understanding aquatic contamination.