UA Researchers Examine EPA Drinking Water Standards; Superfund Scientists Consider Costs, Benefits in Southwest

Researchers at the University of Arizona are reviewing the Environmental Protection Agency's (EPA) proposed standards for arsenic levels in drinking water. UA scientists say the EPA overestimates the health benefits and underestimates costs of the plan.

The EPA proposes a strict new drinking water standard for arsenic in approximately 54,000 community water systems in the United States. Arsenic in ground water is largely the result of minerals dissolving naturally from weathered rocks and soils. Several types of cancer have been linked to arsenic in water.

The primary costs of the proposed standard will be felt in the Southwest, with households paying an estimated $28 to $1,000 more per year, according to the EPA. The EPA estimates the new standard would prevent about 22 bladder and lung cancer deaths per year and about an equal number of non-fatal cancers.

UA scientists, sponsored by the Superfund Basic Research Program at the UA College of Pharmacy, have been working in partnership with utility companies, state regulatory agencies, engineering consulting firms, other universities and public interest groups to review the proposal's impact on the Southwest. The group's comments to be forwarded to the EPA this month include:

  • The proposal overestimates cancer risk associated with arsenic at low doses.
  • The EPA benefits analysis is based on a Taiwanese study, which is not representative of the population and conditions in the United States.
  • The proposal does not adequately address the potential environmental impact of the arsenic removal process.
  • The EPA cost analysis significantly underestimates the actual cost and affordability of meeting the new water standard, particularly in the Southwest.
  • The proposal exaggerates the societal and monetary benefits expected from a lower arsenic standard in drinking water.
  • UA scientists are recommending to the EPA that less strict arsenic standards be implemented initially. The scientists note that the present understanding of the benefits and costs of the plan is inadequate to make a sound judgement, although important research results will be available in the next few years on both the health effects of arsenic and treatment technologies.

The Superfund Basic Research Program at the UA College of Pharmacy has funded an informational website on arsenic in the Southwest at: The UA scientists group was organized by Wendell Ela, Department of Chemical and Environmental Engineering, and Clark Lantz, Department of Cell Biology and Anatomy, and supported by faculty from the UA Colleges of Pharmacy, Medicine and Engineering and Mines.

For general information on arsenic in drinking water, contact the Safe Drinking Water Hotline, at (800) 426-4791, or visit the EPA Safewater website at or the arsenic website at