Heavy Metal- induced Toxicity in Fish: Insights into Molecular Responses

Environmental pollution by heavy metals has evolved to be a huge concern due to its fatal impact on ecosystem health. Extensive application of heavy metals in a wide range of fields including that of agriculture, industry, technology and medicine has led to an increased exposure to the metals. Trace metals are considered to be systemic toxicants known to induce cellular, molecular, biochemical alterations, even at lower levels of exposure. Due to the high sensitivity to dissolved toxicants and the topmost position in aquatic food web, fish is prone to heavy metal toxicity significantly. These metals have been reported to affect DNA and proteins involved in metabolism, detoxification, and damage repair, paving way to carcinogenesis and mortality. Significance of early determination of metal exposure necessitates the need for effective biomarkers that reflects metal induced damage in fish. This review gives an overview on the genetic alterations and molecular changes in fish in response to toxicity induced by heavy metals.