Dietary supplements attenuate the toxicity of heavy metals and enhance their elimination in fish

Abstract

Heavy metals cause a threat to the aquatic environment and to its inhabitants when their concentrations exceed safe limits. This applies to both metals considered priority substances (Pb, Cd, Hg) and trace elements that are necessary for life at appropriate doses (Cu, Zn, Fe, Co, Ni, Mn). They can cause toxic effects in fish due to their non-biodegradable properties and long persistence in the environment. A decrease in heavy metal concentration in organisms observed by various researchers after the use of feed supplements is a positive sign, pointing to the possibility of inhibiting the accumulation and toxic impact of these substances on tissues and organs. In this review article, we demonstrate that certain supplements (such as vitamins, boron compounds, melatonin, lysine, and probiotics), each acting through distinct mechanisms, can reduce the accumulation of heavy metals, significantly mitigate their toxicity in fish, and accelerate their elimination from fish tissues. Consequently, dietary supplementation may positively influence the production of fish intended for human consumption by preventing avoidable losses associated with the deterioration of fish health. Indirectly, it also protects consumers by reducing the risk of exposure to heavy metals that may be present in fish tissues.