Heavy Metal Contamination in Soil: Sources, Accumulation in Vegetables and Remedial Measures: A Review

Presently, rapid industrialization and mechanization create a lot of heavy metal pollution around the globe. Both anthropogenic and natural sources are responsible for the discharge of heavy metal in the environment. Anyhow, these toxic metals reach into soil, water bodies, plants and finally to human beings through the food chain. These toxic metals create several problems in plants and living beings after intake from the soil and get accumulated in their body. Heavy metals also exhibit toxic effects on soil biological activities by affecting key microbial processes and also hamper the activities of soil microbes. Recently, due to industrial development in urban areas, heavy metal contamination has become a serious threat to peri-urban agriculture prevalent for vegetable production. There has long been a need for decontamination of these agricultural resources and prevention from the further contamination to avert the negative effects on living beings. In this article, an attempt has been made to provide an extensive understanding about different sources of heavy metal, such as zinc (Zn), copper (Cu), lead (Pb) and cadmium (Cd) etc., in agro-ecosystem and their possible risks to soil and plants. An effort has been also made to present in brief information on remediation techniques specially phytoremediation through this review.