ガンジスデルタ最大の地下水ヒ素汚染 : シャムタ村における調査結果(アジア地下水ヒ素汚染問題を考える)

概要

論文の詳細を見る
We survyed the arsenic concentration of all tube wells in Samta village, Jessor district, Bangladesh, from 26 to 30 March 1997. The number of wells was 282 and the concentration of other materials in the wells were also measured. This report, however, explains only the concentration of As, NH3-N and Fe. An arsenic contamination map obtained from the survey shows the clear distribution of pollution level from 0.01mg/l to 0.50mg/l. 96.5% of tube wells were unsuitable for drinking according to the WHO guidline (0.01mg/l) and 90% of tube wells contained arsenic above 0.05 mg/l. The highest contamination was recognized compared with the past investigation on arsenic contaminated groundwater in Bangladesh and West Bengal in India. Samta is a small village with an area of 3.2km^2 (residential area:1.5km^2), 620 households and a population of 3,200. The reason why there was a wide variation in arsenic distribution from the concentration value of under 0.01mg/l to over 0.50mg/l in such a small area is not yet identified. In this report, we recommend some countermeasures to solve arsenic problems in Samta village, and further studies including drilling tests to measure arsenic concentration in the soil and groundwater samples at certain intervals. The drilling tests will help to find out the mechanism of arsenic contamination in groundwater.
地学団体研究会の論文
1997-11-07