42 Million May Use Water Fouled by Lead

Lead in drinking water is a serious public health problem, says the U.S. Environmental Protection Agency, noting that as many as 42 million Americans may be consuming water tainted with lead concentrations higher than the EPA’s proposed safe level of 20 parts per billion.

And the extent of the hazard, particularly for children, has been made increasingly clear by new studies suggesting that even smaller concentrations can be harmful, says Jeanne Briskin of the agency’s office of water.

She said the agency is evaluating the studies to see if a lower permissible level should be established, “but even going to 20 parts per billion (from the current 50 p.p.b.) could bring some very substantial health benefits.”

For example, she said, the studies show that about 240,000 children a year would be spared such effects as mental deficiencies, lowered red blood cell counts and stunting of their growth. Several hundred thousand fetuses would have a significantly lower risk of birth defects, she said.

Briskin said that among benefits for adults would be about 310,000 fewer cases of hypertension each year. Excessive lead also can cause progressive kidney damage among adults.

Bigger Piece, Smaller Pie

More attention has focused on lead in drinking water, she said, as levels are reduced in other sources, such as gasoline, paint and food, Briskin said. “The portion of exposure from drinking water is becoming a bigger piece of a smaller pie,” she said.

In California, lead concentrations in drinking water are practically non-detectable at the water treatment plant, according to water agencies and the state Department of Health Services.

But that assurance does not necessarily cover the water finally delivered to the taps of consumers. “The distribution system is the source of contamination,” said Lawrence J. Jensen, assistant EPA administrator for water, noting that lead may be leached out of soldered joints in water mains and building plumbing.

The EPA has banned the use of lead in new public and private water systems and in plumbing repairs. But million of homes, particularly older ones, have plumbing with lead.

Water that stands in pipes overnight or longer may accumulate higher concentrations of lead, so some health officials recommend running water from taps for a minute or more before drinking it.