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PRINT ISSN : 2319-7692
Online ISSN : 2319-7706 Issues : 12 per year Publisher : Excellent Publishers Email : editorijcmas@gmail.com / submit@ijcmas.com Editor-in-chief: Dr.M.Prakash Index Copernicus ICV 2018: 95.39 NAAS RATING 2020: 5.38 |
Lead (Pb) exposure is estimated to account for 0.6% of the global burden of disease with the highest burden in developing regions. Lead is considered as general protoplasmic poison, which is slow acting, cumulative and subtle. The use of leaded gasoline, discharges from industrial activities and other sources, and deposition by rainfall or dry fall can greatly influence the availability of Pb in soil, water, and other environments. Most of the Pb in plants and soil surface are anthropogenic origin. As many of the Pb pollutants are indispensible for human life, soil contamination with lead is not likely to decrease in near future. Severe Pb contamination in soils may cause a variety of environmental problems including loss of vegetation, groundwater contamination, and Pb toxicity in plants, animals, and humans. The cation exchange capacity, pH, organic matter, clay and CaCO3 content can be considered as the most important factors affecting Pb adsorption capacity of soils. Lead may cause the toxic effects on gastrointestinal, muscular, reproductive and neurological systems. Pb is having long half-life in biological systems and plants facilitate entry of Pb in food chains of man and animals. It may enter into our body through ingestion of food or through the blood stream (Johnson, 1998). Recently, accumulator plants for reclaiming Pb polluted soils have increasingly been used. Also, application of phosphate has been reported to be effective in immobilising Pb in soil, leading to reduction in its transfer from soil to plant. Among various reclamation techniques applied for heavy metal, phytoextraction has emerged as less costly, effective method of in situ reclamation. Use of synthetic chelates has improved phytoextraction. Lead with synthetic chelate forms soluble bio-available compounds which may leach down the soil profile and cause ground or water contamination. Hence, approaches of re-vegetation and reclamation, involving both ameliorative and adaptive strategies to allow plant establishment and encourage subsequent vegetation, have emerged.