Household brass plumbing fixtures may release far more lead into drinking water than previously believed, according to a team of Virginia Tech researchers.

In a report published Thursday and trumpeted by the National Science Foundation, the Tech researchers charged that the standards used to certify the brass plumbing supplies found at most hardware stores may be inadequate to predict lead contamination of water.

As a result, even new homes built with brass fixtures like ball valves and water meters could end up with potentially unsafe lead levels under some conditions.

The group's findings, if true, would contradict years of assumptions that lead contamination primarily comes from old leaden pipes or public water systems with lead contamination problems.

"In most circumstances, I don't think lead levels leaching from these devices are an imminent and substantial threat to public health. But in some water systems, it could be a significant concern," said Marc Edwards, a professor in Tech's Department of Civil and Environmental Engineering and co-author of the report.

Edwards is an internationally recognized expert on lead contamination who in 2003 was the first to alert officials in Washington, D.C., to dangerously high levels of lead in public water. He also recently worked with Montgomery County municipalities to ensure the safety of a new water treatment system.

Officials with the National Sanitation Foundation, which certifies plumbing supplies as safe, disagreed with some of the researchers' findings but said aspects of the testing procedures are under review.

Contrary to popular belief, many plumbing supplies sold today are not lead-free.

Amendments made to the federal Safe Drinking Water Act in 1996 banned plumbing devices with pure lead pipe but still allow up to 8 percent lead content in brass fixtures. Lead makes brass and other metals more malleable, helping manufacturers create intricate shapes.

The National Sanitation Foundation led the effort in 1988 to develop standards aimed at controlling the amount of lead and other contaminants that can leach into water supplies from plumbing products.

The research team, which consisted of three researchers from Tech and one from the U.S. Environmental Protection Agency, focused on one area of the standards that dealt with "in-line" plumbing such as ball joints, check joints and water meters. Faucets and similar fixtures are covered under a different section.

Products that pass the testing process receive the "ANSI/NSF 61-8" mark, signaling they are safe to use.

But Edwards and his co-researchers are questioning the efficacy of those testing procedures and the accuracy of the results.

The crux of the group's criticism focuses on the two pH levels in the testing water. Researchers said the one level was too low to draw lead out of the brass while the higher pH lost its leaching effectiveness after several days.

The testing water also contained an additive that suppresses lead leaching, but that additive is not universally used in drinking water systems. The combination of those factors means the tests may not accurately reflect real-world water conditions and appear too lax to protect public health, Edwards said.

In one instance, a pure lead pipe tested by the Tech group passed the sanitation foundation standards.

"It's analogous to testing automobile safety ... by crashing into a wall of pillows," Edwards said.

Abhijeet Dudi, who conducted much of the research as part of his master's thesis at Tech, said he at first didn't believe the findings. But after repeated testing, it became clear that new brass fixtures could, indeed, leach significant levels of lead under certain water conditions.

David Purkiss, general manager of water distribution systems at the sanitation foundation, said the agency recently revised its testing procedures to require that higher pH water be made daily based on the researchers' findings.

But Purkiss disputed other aspects of the research paper, saying the lower pH was never intended to produce lead leachings but is geared more toward copper and nickel.

The foundation has created a task force to review the standards. One aspect under consideration is whether testers should expose brass fixtures to more varieties of water and common additives to better simulate real-world conditions.

"We are looking at ways to improve it and at the comments Marc has made," Purkiss said. "The research he has done has been very helpful."

In the meantime, Purkiss said the foundation stands by its standards and recommended homeowners continue looking for the ANSI/NSF-61 mark.

Several members of Congress have introduced legislation to strengthen the nation's protections against lead water contamination in response to the problems in Washington as well as the Tech research. The bills would also lower the allowable percentage of lead in brass fixtures.

Edwards said the brass industry as well as plumbing fixtures manufacturers have responded "very aggressively" to the concerns raised by the research. While he was initially disappointed with the sanitation foundation response, Edwards said he was pleased its officials are reviewing the standards.

Edwards said that the research group's findings, while admittedly alarming, are no reason for homeowners to panic.

"If it were my family, I wouldn't consider replacing my plumbing," he said. "I would consider doing some testing of the water."

For those homes with high lead levels he offered a simple solution: Purchase one of the relatively inexpensive water filtration systems, such as those made by Brita, found in most supermarkets.Lead in water may stem from plumbing