Arsenic in private drinking water wells: an assessment of jurisdictional regulations and guidelines for risk remediation in North America

Arsenic is a known carcinogen found globally in groundwater supplies due to natural geological occurrence. Levels exceeding the internationally recognized safe drinking water standard of 10 μg/L have been found in private drinking water supplies in many parts of Canada and the United States. Emerging epidemiological evidence confirms groundwater arsenic to be a significant health concern, even at the low to moderate levels typically found in this region. These findings, coupled with survey data reporting limited public adherence to testing and treatment guidelines, have prompted calls for improved protective measures for private well users. The purpose of this review is to assess current jurisdictional provisions for private well water protection in areas where arsenic is known to naturally occur in groundwater at elevated levels. Significant limitations in risk management approaches are identified, including inconsistent and uncoordinated risk communication approaches, lack of support mechanisms for routine water testing and limited government resources to check that testing and treatment guidelines are followed. Key action areas are discussed that can help to build regulatory, community and individual capacity for improved protection of private well water supplies and enhancement of public health.