Arsenic drinking water limit

Arsenic is a known human carcinogen, found in drinking water in many parts of the world. The World Health Organization (WHO) has set the upper limit for arsenic in drinking water at ten parts per billion (10 ppb). The legal limit in the United States, set by the Environmental Protection Agency (EPA) is 50 ppb. 

There is limited evidence of carcinogenicity in experimental animals. However, in one report arsenic administered for 2 years in the drinking water of female mice was associated with an increased incidence in tumors involving lung, liver, gastrointestinal tract, and skin. ... 

Spike recovery and detection limit. Species of arsenic found in drinking water include AsO (arsenite), AsO - (arsenate), (CH3)2As02 (dimethylarsinate), and (CH3)AsO (methylarsonate). Pure water containing no arsenic was spiked with 0.40 pg arsen-ate/L. Seven replicate determinations gave 0.39, 0.40, 0.38, 0.41, 0.36, 0.35, and 0.39 pg/L.12 Find the mean percent recovery of the spike and the concentration detection limit (pg/L). 

N/ Groundwater, drinking water, or porewaters Abundant literature exists on arsenic contamination problems in some countries (e.g. Bangladesh). In such cases, the tables in this appendix simply list a few of the more recent key references, which provide overall and concise summaries of the problems. For other regions and countries (e.g. Laos), arsenic contamination has been identified as a significant problem, but further details are not readily available. In these situations, the reference(s) with the limited information is listed. No public information is readily available on arsenic contamination in North Korea, many of the republics of the former Soviet Union, and... 

California s Safe Drinking Water and Toxic Enforcement Act of 1986 (Proposition 65) restricts the use and disposal of antimony, arsenic, beryllium, cadmium, hexavalent chromium, lead, and nickel compounds, without specifying limits. 

Focazio M. J., Welch A. H., Watkins S. A., Helsel D. R., and Horng M. A. (1999) A Retrospective Analysis of the Occurrence of Arsenic in Groundwater Resources of the United States and Limitations in Drinking Water Supply Characterizations. US Geological Survey, Water Resources Investigation Report 99—4279, 11pp. 

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