ABSTRACT
Heavy metals pollution has become a global environmental issue as it has contaminated every sphere of the earth. Due to the increase in population with rapid growth in industrialization and urbanization metal contamination has increased at an alarming rate. Metal pollution is caused by both natural and human activities. Metals are not biodegradable, they are persistent in the environment, and tend to accumulate in the organism due to biomagnification. The metals contaminate all ecosystems, affect organisms residing in them, and eventually deteriorate human health through the successive transfer of metals in the entire food chain. Since plants can absorb heavy metals from both soil and water, metals hamper crop productivity and reduce its nutritional value. Thus, metal affects the health of human beings both directly and indirectly. This chapter explains the different sources of heavy metal, their forms and distribution in soil, the cycling of metals in the ecosystem, its trophic transfer through the food chain, its effect on the different ecosystems, crop productivity, and human health. This chapter comprehensively deals with the impact of heavy metals on the ecosystem in different contexts.
