Critical Review: Arsenic in Water-soil-food Chain in Bangladesh

摘要

In Bangladesh, more than 35 million people are consuming arsenic-polluted ground water in 59 districts out of 64 administrative districts. In addition to arsenic problem in drinking water, continued cropping with arsenic contaminated irrigation water increases the extent of contamination in agricultural land. Objective of this paper is to provide a knowledge base on arsenic polluted irrigation water on soil and on plant growing on contaminated soil and to provide a clear understanding on the new unrevealed arsenic exposure pathway of distressed people of Bangladesh through water-soil-food chain. Use of arsenic contaminated irrigation water for growing crops in arsenic rich soil may lead to crop yield losses and elevated arsenic concentrations in cereals, vegetables and other agricultural products. The average arsenic concentration of the rice grain and other plant sample exceeds permissible limit of 1 mg/kg in very limited cases. Arsenic concentration observed in much higher range in roots and straw than leaves and rice grains. This study also summarized the fate of arsenic in plant soil environment and the arsenic uptake mechanisms of plant's root zone proposed in literature. It is necessary to establish some procedure for arsenic cleanup from soil to get rid of the situation.