WASHINGTON (AP) _ Within five years, drinking water in the United States will have to meet a new and tougher arsenic standard now being adopted by the Bush administration.
The administration's about-face Wednesday on a standard issued in the last days of the Clinton presidency will be felt particularly in rural towns among Western mining states where arsenic, both a naturally occurring substance and industrial byproduct, is found in high concentrations.
Environmental Protection Agency Administrator Christie Whitman said the decision to adopt the new standard will reduce the maximum amount of arsenic allowed in drinking water from 50 parts per billion _ a level first set in 1942 _ to 10 ppb by 2006.
``A standard of 10 ppb protects public health based on the best available science and ensures that the cost of the standard is achievable,'' Whitman said in a letter to House Appropriations Chairman Rep. Bill Young, R-Fla.
One part per billion is the equivalent of one drop of water in a 10,000 gallon swimming pool.
Last month, the National Academy of Sciences issued a report to Whitman saying the agency had greatly underestimated the cancer risks of arsenic in drinking water.
The risks are much higher than the agency had acknowledged even for low levels of arsenic in tap water, the report said. Even at 3 ppb, it said, the risk of bladder and lung cancer from arsenic exposure is between four and 10 deaths per 10,000 people. The EPA's maximum acceptable level of risk for the past two decades for all drinking water contaminants has been one death in 10,000.
The Natural Resources Defense Council, an environmental group whose lawsuits pushed the Clinton administration to propose the new standard, says Whitman should have announced a 3 ppb standard if she were really basing her decision on sound science.
Whitman had asked the academy to study the health effects of establishing a standard of 3, 5, 10 or 20 parts per billion. At each level, the study found, the cancer risks were much higher than the EPA had estimated.
``The scientific evidence now proves we need a standard of 3 ppb to protect health,'' said Erik D. Olson, a senior lawyer for NRDC. ``Her review was a charade, and her decision will threaten the health of millions of Americans.''
The EPA estimates that one in 20 water systems, or about 4,100 nationwide, will have to treat their water to meet the new standard. Some 97 percent of those are small systems serving communities of fewer than 10,000 people.
To help ease the financial burden, the EPA plans to provide $20 million for researching the most cost-effective technologies to meet the new standard, Whitman said.
``These communities will need help if they are to comply with the standard,'' said Sen. Harry Reid, D-Nev., who supports the 10 ppb standard but hopes Congress will provide $750 million annually so many of the towns and native tribes like those in his mining state can upgrade their water systems.
Former President Clinton had adopted the 10 ppb standard three days before leaving office. The Bush administration suspended that action until next February and left in place the 50 ppb standard, citing at least $200 million in new costs to local communities and questioning the scientific basis behind the new standard.
Costs of compliance for major water systems, however, would be less than $1.50 a month per household, EPA estimates.
In July, EPA also began gathering public comment; Wednesday was the deadline for submissions. Critics say the new standard will be tough for some to meet.
``In a lot of instances this is going to do more harm than good. In a small community, you have limited public health dollars,'' said Mike Keegan, a policy analyst for the National Rural Water Association, whose study estimated the new costs to be $400 million.
The report pointed to health effects other than cancer that should be considered, including heart disease, high blood pressure and diabetes. It also rejected arguments that there is a clear, safe threshold below which arsenic does not cause cancer.