Health risks downplayed
BANGOR, Maine — The public water system that serves some 50,000 Bangor-area residents has tested high in lead for the first time since routine testing began in 1992. The health threat is not great, according to Kathy Moriarty, general manager of the Bangor Water District, and local and state health officials agree.
“I think there is really a pretty minimal public health threat,” said Patty Hamilton, director of public health for the city of Bangor. “We really don’t want to be alarmist about this.”
But with levels exceeding the acceptable level of lead in drinking water established by the federal Environmental Protection Agency, the water district must now conduct a broad-based public awareness campaign in the seven communities it serves, review its water-treatment processes, and implement a ramped-up testing schedule.
Moriarty will present information about the test findings, the educational campaign and ongoing water monitoring Monday evening at the regular meeting of the Bangor City Council.
Moriarty said the EPA standard represents an “action level” — a red flag for the water system to review their process — and does not in itself indicate a danger to public health. The Bangor Water District serves customers in Bangor, Eddington, Clifton, Orrington, Hampden, Veazie and Hermon.
Exposure to lead can cause lowered intelligence, neurological problems, and brain and kidney dysfunction in adults and children. Pregnant women, infants and young children are at the greatest risk.
Public health experts say that using water from the cold-water tap instead of the hot water tap for drinking and cooking and allowing the water to run for two to three minutes before using it minimize the risk of exposure to lead. Some filters also may be helpful in removing lead from tap water.
The presence of lead in public water supplies is almost always due to leaching from lead pipes and lead solder. Leaching is made worse by water that is very acidic. Neither lead pipes nor lead solder is found within the Bangor Water District’s extensive system of underground mains and services, according to Moriarty, although many older individual homes and businesses in the area retain both. The pH of the water is maintained at a slightly acidic 6.2 and has not changed in many years, she said.
“It really surprised us that we exceeded the [acceptable] level,” Moriarty said. “It’s troubling, because we can’t clearly identify any changes in our treatment process that would cause it.”
Moriarty said the water district already has begun the complex task of reviewing its treatment protocols. Other possible factors might include warmer than usual temperatures over the summer, she said, or human error in collecting the water samples, which are collected by the homeowners.
Moriarty stressed that water samples drawn at the test sites after the water was allowed to run for a few minutes tested well below the EPA standard.
Mandatory testing of public water supplies for lead and copper began nationwide in 1992.
Based on the approximately 11,000 addresses to which it delivers treated water, the Bangor Water District must monitor a minimum of 30 residential sites; in 1992, the district chose 46 sites to monitor, all of them in Bangor.
Because lead in drinking water is most often associated with the presence of lead solder and brass fixtures, the test sites were selected for the presence of these materials. Lead solder was taken off the market in 1986, so plumbing systems in homes constructed before that year are likely to contain the material. But in very old homes, the water pipes are likely to have developed an inner coating of mineral deposits that helps prevent lead from leaching into the water. So the Bangor homes selected for testing were built between 1982 and 1986 — old enough to have lead solder but not so old that they have developed the mineral deposits in their plumbing.
“This regulation makes sure we’re protecting our most vulnerable homes,” said Dina Page, water quality manager at the Bangor Water District. “The EPA wants to ensure we test the worse-case scenario conditions.”
All samples are drawn by the homeowner from taps where the water has been sitting undisturbed for at least six hours, usually in a kitchen, she said.
Initially, testing for lead and copper was required every six months, but because the water at the selected sites in Bangor consistently tested at or below the allowable levels, frequency of testing was allowed to decrease to every three years. The last tests were conducted in 2007.
All 46 sites have remained well below the allowable level for copper. Just once, in 2002, lead levels touched the maximum acceptable 15-parts-per-billion threshold. But this year, the test results showed elevations at eight of the 46 sites, ranging from 18 ppb to 60 ppb. The figure reported to the EPA is the 90th-percentile level of 23 ppb.
There is no obvious explanation for the sudden spike. Lead is not found in the water of Floods Pond, Page said. Nor has there been any recent change in the way the water is treated at the 2005 treatment plant beside the pond before it begins its gravity-driven journey to Bangor.
At the Division of Environmental Health in the Maine Center for Disease Control and Prevention, Director Nancy Beardsley said pristine Floods Pond is “the poster child of all water sources” and not the source of the lead.
Because the Bangor Water District owns not only the entire perimeter of the pond but also most of the watershed that feeds it, there is essentially no source of contamination, she said.
“For a surface water source, it is really the absolute best circumstance for maintaining water quality,” Beardsley said. “Bangor is very fortunate to have Floods Pond as its water source.” Beardsley also praised Moriarty’s expertise and professionalism in running the Bangor system.
Of the 760 public water systems in Maine that are required to test for lead, 20 have exceeded the EPA standard this year, Beardsley said. In 2009, 22 systems exceeded the limit and in 2008, 39 did. The state is working with all these systems to ensure public safety while the source of the problem is identified and corrected.
While it can take years to correct a problem of lead in a public water system, Beardsley, Hamilton, Page and Moriarty all said the essential public health message for consumers is fairly simple: Always use water from the cold water tap for drinking, cooking and mixing baby formula, and always let the water run for a few minutes to flush out any lead that may be in the pipes.
While it can take years to sort out the factors contributing to elevated levels of lead in a water system, the public health message is straightforward:
- Always use water from the cold-water tap for drinking, cooking and mixing baby formula.
- Let water run for several minutes to flush out any lead in the pipes.
- Consider having the water from your kitchen faucet tested for lead.
Bangor Water District General Manager Kathy Moriarty will present information on the district’s response to the latest lead test results at the next regular meeting of the Bangor City Council, at 7:30 p.m. Monday, Oct. 25, in council chambers at City Hall.
Bangor Water District customers soon will receive an informational brochure in the mail concerning the recent lead testing and the district’s response. Additional information, including a list of private laboratories where customers may have their water tested, is available on the district’s website www.bangorwater.org or by calling 947-4516, ext. 409.