Efficacy of flocculent technology as an arsenic mitigation strategy

Project Summary

This study is designed to evaluate the effectiveness and assess the acceptance and use patterns of a point-of-use water treatment method to improve the microbiological and chemical composition of drinking water. The investigation will be conducted in rural Bangladesh in villages where the water supply contains arsenic levels above the national standard of 50 ppb. It is estimated that 65% of the 4 million tube wells constructed in an attempt to provide a microbiologically safe drinking water source, may contain toxic levels of arsenic in their water. To date, approximately 25 million people have been exposed to arsenic-contaminated drinking water and over 7,000 patients have been identified with the manifestations of arsenicosis. A number of arsenic mitigation strategies, predominantly consisting of structural and filtering treatments, have been recommended to those at risk; however acceptance and use rates have been less than optimal despite active educational efforts. The use of alternative sources including surface water, reintroduces the risk of illness from diarrhoeal disease resulting from the ingestion of pathogenic organisms known to inhabit untreated surface water sources. As tube well water is accessible and acceptable as a drinking source, it would be beneficial to implement a method that would remove arsenic from the tube well water thus reducing the exposure of the population at risk to elevated arsenic levels. Additionally the flocculent technology proposed for use in this efficacy study has the advantage of reducing the microbiological contamination of treated water through its chlorination activity. Therefore, the problems of both arsenic contamination and microbiological contamination of tube well water would be addressed with the use of the proposed technology.