Asen ô nhiễm nước ngầm ở Bangladesh đã nổi lên như trường hợp ô nhiễm nước lớn nhất trên thế giới. Ở Bangladesh, nó đã được nghĩ rằng hơn 97% dân số đã tiếp cận với nước uống an toàn cho đến gần đây và bởi vì phát hiện asen trong nước ngầm, nguồn nước uống ở các vùng nông thôn và thành thị, truy cập đã giảm đến 80 %. Sự gia tăng gần đây trong sản xuất lúa gạo cũng là do nước ngầm để tưới tiêu và khoảng 70% nước tưới là trừu tượng từ các tầng. | Section 5 Management of arsenic-rich groundwaters Copyright 2005 Taylor Francis Group plc London UK Natural Arsenic in Groundwater Occurrence Remediation and Management -Bundschuh Bhattacharya and Chandrasekharam eds 2005 Taylor Francis Group London ISBN 04 1536 700 X Management of the groundwater arsenic disaster in Bangladesh . Ahmed Department of Geology University of Dhaka Dhaka Bangladesh ABSTRACT Arsenic contamination of groundwater in Bangladesh has emerged as the largest water pollution event in the world. In Bangladesh it had been thought that more than 97 of the population had access to safe drinking water until recently and because of detection of arsenic in groundwater the main source of drinking water in rural and urban areas the access has come down to 80 . The recent increase in rice production is also attributed to groundwater irrigation and about 70 of irrigation water is abstracted from the aquifers which account for 85 of the total abstracted groundwater. The presence of arsenic in groundwater has become a major issue of management of both drinking and irrigation water in the country. Analysis of about 4 million wells by field kit show that about one third of the wells exceed the BDWS of 50 rg L. If the WHO provisional guideline value 10 rg L is considered two thirds of the wells become unsafe. About 30 to 70 million people are exposed to unsafe level of arsenic in their drinking water. Yet another potential intake source remains unknown . the entries through the food chain due to irrigation with arsenic contaminated groundwater. Scientific investigations have demonstrated that arsenic contamination does not occur randomly rather geology and hydrogeology control it. Groundwater in Bangladesh has never been considered as a precious resource rather it has been used indiscriminately. For management of arsenic in groundwater a pragmatic mitigation policy is needed with a holistic approach. Legal and institutional reforms are necessary to .
