The U.S. Environmental Protection Agency (EPA) yesterday took steps to reduce the limit for arsenic allowed in drinking water to one-tenth the current standard in an effort to reduce cancer risks.
The agency is proposing to reduce the arsenic allowed in drinking water from 50 parts per billion to 5 parts per billion.
The proposal would provide additional protection to at least 22.5 million Americans from cancer and other health problems.
"Our tap water is among the safest in the world, with more than 90 percent of Americans served by community water systems receiving water that meets tough federal standards," said EPA Administrator Carol M. Browner. "Since 1993, 23 million more Americans receive water that meets tough federal health standards. We will continue to take actions to protect public health by strengthening existing standards when necessary, as we are doing today."
In March 1999, the National Academy of Science (NAS) completed a review of updated scientific data on arsenic and recommended that EPA lower the standard as soon as possible.
Although the NAS did not recommend a specific numeric level, its recommendation formed the basis for EPA''s proposal.
All 54,000 community water systems, serving 254 million people would be subject to the new standard.
However, EPA estimates that only 12 percent of community water systems, approximately 6,600, would need to take corrective actions to lower arsenic levels in drinking water to 5 parts per billion.
In general, arsenic can contaminate drinking water through natural processes, such as erosion of rocks and minerals.
Arsenic can also contaminate drinking water when used for industrial processes. It is found at higher levels in underground sources of drinking water than in surface waters, such as lakes, reservoirs, and rivers.
Water systems in western states and parts of the Midwest and New England that depend on underground sources of drinking water will be most affected by this proposal.
Arsenic in drinking water can cause cancer and other health problems, including cardiovascular disease and diabetes, as well as developmental and neurological effects.
EPA is asking for public comment for 90 days about lowering the standard. After reviewing the comments, a final rule could be put in place by early 2001.
Additional information on safe drinking water is available at www.epa.gov/safewater.
by Virginia Sutcliffe