Alison Young

USA TODAY

Nearly a year ago, officials from the U.S. Environmental Protection Agency said work was underway to create a health-hazard standard for lead in drinking water, records from agency advisory group meetings show.

Yet despite growing public concern about high levels of lead coming out of taps in Flint, Mich., as well as at homes and schools in all 50 states, the EPA still hasn’t released results of computer models estimating what level of lead in water poses a serious health threat and should trigger local health department help for families.

“People across the country and in Flint need to know what EPA thinks the level is at which a household should consider taking action,” said Tom Neltner, a member of the EPA’s lead and copper work group and chemicals policy director for the Environmental Defense Fund.

“I think it’s stuck within the EPA decision-making,” Neltner said. “I think they have it. I think they are arguing about it.”

Beyond Flint: Excessive lead levels found in almost 2,000 water systems across all 50 states

EPA officials declined to grant an interview and did not answer USA TODAY NETWORK questions about why the analysis is taking so long and what deadlines agency leadership has set to ensure timely progress.

“EPA is analyzing data on lead exposure, blood lead level models and exposure pathways," the agency said in an emailed statement. "Once the agency has a scientifically robust analysis, and completes internal agency reviews, we intend to seek external peer review.”

The EPA hasn't begun an internal review yet because, among other things, it still is evaluating approaches that at least five offices within the agency use for predicting a person's blood-lead level based on exposures, the statement said. The goal is for the level to be included in a package of regulatory proposals the agency expects to publish sometime in 2017.

Current EPA regulations do not include a health-hazard standard for lead in drinking water. In regulating water systems, the EPA has set what it calls an “action level” for lead of 15 parts per billion to trigger water-treatment actions if more than 10% of faucets sampled exceed that level.

But the number is only an engineering standard that, when it was set in 1991, was considered to be the lowest amount of lead in water that systems could achieve reliably through adding anti-corrosion chemicals.

“Right now people are using the current action level as if it had meaning for health, even though it is not based on health,” Neltner said

Some studies have documented harm from drinking water contaminated at far lower levels. The EPA and the federal Centers for Disease Control and Prevention both say lead in drinking water is not safe at any concentration.

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The EPA has set a maximum contaminant goal of zero for lead in drinking water. The goal is not enforceable, and experts say it also is impossible to achieve because millions of U.S. homes receive water that passes through lead pipes and plumbing.

Without a health-hazard level, the public and water systems can't put lead test results in any context or know when immediate action is needed, said Marc Edwards, the Virginia Tech water engineering expert whose team has independently investigated Flint’s contamination issues.

“You have to have some level that requires people to know when their health is in danger,” Edwards said. “Whatever they set, I think they’re fearful of the fallout.

"People are measuring lead in schools again, and they’re getting levels in the hundreds of parts per billion,” he said.

This month, a USA TODAY NETWORK investigation revealed that nearly 2,000 water systems serving about 6 million people have failed to meet the EPA’s existing lead standard since 2012. About 350 of the failing systems are dedicated to serving schools and day care centers, and about 600 of the systems had tests at some taps showing lead levels topping 40 ppb, EPA enforcement data show.

"Your series has really driven it home, more so than anyone else, how widespread this problem is," Edwards said. "EPA has to make a decision about some level of contamination that poses a health threat."

Meeting minutes from an EPA drinking water expert advisory group indicate agency staff made progress coming up with a health hazard number last year and thought it might even be released by late 2015.

As of this past April, EPA staff told the lead and copper working group that the agency had an existing computer model to help determine what level of lead in a home’s tap water posed a serious health risk. Joyce Donohue of EPA’s Office of Science and Technology discussed factors that would need to be considered in the modeling.

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At that time, the working group was in the process of drafting recommendations for creation of a household action level for lead.

The group’s recommendation was for the EPA to come up with a level of lead in drinking water that posed a health danger to those considered.

At greatest risk were infants fed formula made with tap water, the group said. The modeling should establish a hazard level that would protect them from having dangerous levels of lead in their blood.

If a water test found lead above this household action level, the group wanted public health experts notified so they could investigate and help.

In June, records show that members asked about the EPA’s progress in developing a household action level, which EPA officials dubbed HAL.

Eric Burneson of the EPA’s Office of Ground Water and Drinking Water “indicated that EPA is working on establishing the HAL, but that it will take some time because the HAL must undergo a peer review and quality assurance. It may or may not be available for the full (advisory council) meeting in late 2015.” Burneson is the director of the water office’s standards and risk management division.

“Nine months ago, EPA said it needed to complete quality assurance and peer review before releasing a draft household action level,” Neltner said.

But he said he believes that the EPA has an obligation as a public health agency to release information about a hazard level as quickly as possible.

How much lead in water poses an imminent threat?

"It makes no sense to wait for rulemaking to help parents who must decide whether to invest in a filter for the water they use to make up their child’s infant formula," he said.

The lead and copper working group is part of the EPA’s National Drinking Water Advisory Council, which in December formally sent numerous recommendations to the agency, including for the creation of the household action level. Jill Jonas, advisory council chairwoman and the drinking water chief for the Wisconsin Department of Natural Resources, declined to be interviewed.

Several of the experts who served on the advisory council's 16-member lead and copper working group were traveling, unavailable or declined to be interviewed.

June Swallow of the Rhode Island Department of Health said through a spokesperson that she doesn’t recall the EPA committing to a particular time frame for developing the health-action level. Evaluating how long it should take “is not her area of expertise,” she said.

Leon Bethune of the Boston Public Health Commission, declined to be interviewed about the EPA's progress developing the action level. Through a spokesperson, he issued a statement: “It was a great experience meeting with the folks from health departments and water utilities from around the country, using our own experiences, knowledge and research to come to consensus on how to improve the lead and copper rule.”

Another working group member, Lynn Thorp of the advocacy group Clean Water Action, said in an interview the EPA indicated last year that agency staff were working to create the household-action level.

“I don’t know why it hasn’t come out yet,” Thorp said. “If there is a gap in public health and exposure science or other data that we need to answer this question, then we need to know that so there can be public support for government agencies undertaking that work.”

How much lead in water poses an imminent threat?

From at least 2002 into 2004, archived webpages show the EPA’s website said a lead concentration of 40 ppb or more in drinking water was cause for "immediate action." At that level, the water posed an “imminent and substantial endangerment to the health of children and pregnant women.”

The agency acknowledged the level was on its website for several years but told the USA TODAY NETWORK it never was formally adopted and hadn't undergone peer review. The EPA removed references to the 40 ppb hazard level during an earlier lead-contaminated water crisis in the District of Columbia.

Read the USA TODAY NETWORK's "Beyond Flint" investigation of lead contamination in water nationwide at lead.usatoday.com

Follow investigative reporter Alison Young on Twitter: @alisonannyoung

Investigation: Lead in Your Drinking Water