Heavy Metal Contamination in Food: Sources, Impact, and Remedy

Heavy metal contamination of food crops and seafood is a growing global concern with severe health risks to humans and animals. This contamination often originates from both natural and man-made sources, including agricultural practices, mining, industrial emissions, and improper waste disposal, and poses a threat to both terrestrial and aquatic ecosystems. Common heavy metal contaminants, e.g., Cd, Cr, Hg, Pb, Cu, Zn, and As, have biotoxic effects, which raise significant concerns about their impact on human biochemistry. Heavy metals are nonbiodegradable, heightening environmental and human health risks, as they persist, accumulate, and magnify in soil and water. Contaminated agricultural soils and water sources not only compromise soil health and aquatic ecosystems but also jeopardize food quality and safety. Plant uptake is a significant pathway for heavy metals to enter the food chain, making monitoring food quality imperative. Understanding the mechanisms of metal toxicity, including concentrations and oxidation states, is crucial for effective management. Heavy metal exposure can result in developmental retardation, various cancers, kidney damage, endocrine disruption, neurological disorders, and more. Conventional reclamation methods face challenges in achieving complete remediation and are economically less viable. In response, nature-based solutions, such as bioremediation, including phytoremediation and microbially mediated bioremediation, emerge as promising alternatives. Microorganisms’ biosorption of heavy metals can curtail the transfer of contaminants from soil to plants. Plants exhibiting rapid growth and the ability to accumulate metals present opportunities for phytoremediation or phytoaccumulation. The chapter discusses the harmful effects of heavy metal exposure on human health and biodiversity and proposes nature-based solutions to mitigate its impact. Bioremediation techniques provide an ecologically sound and economically viable approach to managing heavy metal contamination. This approach ensures a safer and healthier food supply, addresses the critical issue of heavy metal contamination, and promotes sustainable environmental and human health practices.