Ground Water Arsenic Contamination in Malda, West Bengal, India: Epidemiology and Efficacy of Mitigation Measures

Background and Objectives: Health hazard due to arsenic exposure through ground water is a major problem in West Bengal. The State Government is involved in supplying arsenic safe water to the population. An epidemiological study is done on Malda, one of the severely arsenic affected district of West Bengal. Quality of drinking water and its availability to the people have also been assessed. Methods: A population based cross sectional study was done in Malda. Water from household tube well was tested for arsenic and availability of safe water was assessed. Results: Four hundred and forty-six (8.3%) cases of arsenicosis with typical skin lesion were detected out of 5355 participants examined in 2013 households studied in seven affected blocks of Malda. Out of 1638 water samples tested from home tube wells, 78% of water samples were found to be contaminated with arsenic >0.01 mg/L. Out of 81 habitations surveyed, 68 habitations had pipelines constructed for supplying arsenic safe water. However, supply was regular in four habitations only. Arsenic safe water (<0.01mg/L) was available from 5 tube wells out of 21 tube wells constructed by PHED in the habitations. Interpretation and Conclusion: Significant number of arsenicosis cases were identified in Malda district. Large number of home tube wells were contaminated with arsenic. In spite of presence of PHED tube wells and pipelines in most arsenic affected habitations, safe water was not available to most people.