Toxic Heavy Metals On The Environment Essay

1500 Words Sep 5th, 2016 6 Pages
Toxic Heavy Metals on the Environment
Introduction
Heavy metals are defined as metallic elements that have a relatively high density compared to water with the assumption that heaviness and toxicity are inter-related, heavy metals also include metalloids. Heavy metals are naturally occurring elements that are found throughout the earth’s crust, most environmental contamination and human exposure result from anthropogenic activities such as mining and smelting operations, industrial production and use, and domestic and agricultural use of metals and metal-containing compounds (Tchounwou et al., 2012). The following are major toxic heavy metals: mercury, lead, arsenic, cadmium, nickel, gold, platinum, bismuth, selenium, vanadium, chromium and thallium (Botkin& Keller, 2014). Each of these elements may be found in soil or water and they all have uses in industry (Botkin& Keller, 2014). Environmental contamination can also occur through metal corrosion, atmospheric deposition, soil erosion of metal ions and leaching of heavy metals, sediment re-suspension and metal evaporation from water resources to soil and ground water (Tchounwou et al., 2012). Industrial sources include metal processing in refineries, coal burning in power plants, petroleum combustion, nuclear power stations and high tension lines, plastics, textiles, microelectronics, wood preservation and paper processing plants (Tchounwou et al., 2012). Heavy metals are also considered as trace elements because of their…

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