U.S. Moves to Limit Arsenic in Drinking Water

By Cat Lazaroff

WASHINGTON, DC, January 18, 2001 (ENS) - The U.S. Environmental Protection Agency moved Wednesday to reduce public health risks from arsenic in the nation's drinking water. The agency is establishing a new arsenic standard for drinking water that is five terms more stringent than current regulations.

Announcing the new rule, President Bill Clinton said the action will provide additional protection to at least 13 million Americans from cancer, cardiovascular disease and other health problems.


The EPA's new arsenic standard will make drinking water safer for an estimated 13 million Americans (Photo courtesy EPA)
"When we turn on our taps, Americans expect the water that comes out to be clean and safe," said President Bill Clinton, announcing the new rule. "Access to clean, safe water is fundamental to our quality of life."

The new rule reduces the allowable levels of arsenic in drinking water to 10 parts per billion (ppb), down from the current 50 ppb level. The new U.S. standard matches that recommended by the World Health Organization.

All 54,000 U.S. community water systems, serving 254 million people will be subject to the new standard. The EPA estimates that roughly five percent, or 3,000, community water systems serving 13 million people, will need to take corrective action to lower current arsenic levels in their drinking water.

The standard also applies, for the first time, to 20,000 water systems that serve people only part of the year, such as schools, churches and factories. About 1,100 of these systems, serving two million people, will need to take corrective action. Most of the systems affected by the new standard serve fewer than 10,000 people.

Water systems in western states and parts of the Midwest and New England that depend on underground sources of drinking water will be affected most by the new standard. Arsenic is found at higher levels in underground sources of drinking water than in surface waters, such as lakes, reservoirs and rivers.


Long term arsenic exposure can lead to skin lesions and keratosis, a hardening of the skin (Photo courtesy World Bank)
Arsenic occurs naturally in rocks and soil, water, air, and plants and animals. It can be released into the environment through natural activities such as volcanic action, erosion of rocks, and forest fires, or through human actions. About 90 percent of industrial arsenic in the U.S. is used as a wood preservative, but arsenic is also used in paints, dyes, metals, drugs, soaps and semi-conductors. Agricultural applications, mining and smelting also contribute to arsenic releases in the environment.

Studies have linked long term exposure to arsenic in drinking water to cancer of the bladder, lungs, skin, kidney, nasal passages, liver and prostate. Arsenic exposure can cause other health problems as well, including cardiovascular, pulmonary, immunological, neurological and endocrine effects.

The earlier 50 ppb arsenic standard for drinking water was set by EPA in 1975, based on a Public Health Service standard originally set in 1942. In March 1999, the National Academy of Sciences (NAS) completed a review of updated scientific data on arsenic and recommended that EPA lower the standard as soon as possible.

On June 22, 2000, EPA proposed a new drinking water standard of five ppb for arsenic and requested comment on options of three ppb, 10 ppb and 20 ppb. EPA evaluated over 6,500 pages of comments, and ultimately opted for the new 10 ppb standard under pressure from industry groups.

"It's a significant step forward for public health," said Erik Olson, senior attorney for the conservation group Natural Resources Defense Council. "The new rule will help alleviate the deadly problem of arsenic contamination in tap water consumed by millions of Americans. But we are disappointed that EPA, which wanted a tighter standard, could not fight off regressive industry lobbyists who care little about public health."


In the U.S., arsenic is primarily used to preserve wood for fencing and other outdoor uses (Photo courtesy CSIRO Forestry and Forest Products)
"We urge the agency to lower the arsenic level in drinking water to a level of three ppb or less when carries out its mandatory review of the standard sometime in the next six years," Olson said.

EPA estimates that 90 percent of households served by systems needing treatment will have increased annual costs of $60 or less per household. Most water systems will have five years to comply with the new rule, but small systems needing financial assistance to meet the new requirements can receive compliance extensions of up to nine years.

More information on the new standard is available at: http://www.epa.gov/safewater/arsenic.html

A map of arsenic distribution in groundwater across the U.S., prepared by the U.S. Geological Survey, is available at: http://co.water.usgs.gov/trace/arsenic