A city worker flipped the switch and fluoride filled the veins of Juneau’s drinking water supply Wednesday – the same day a federal report’s release may have given ammunition to those seeking a fluoride-free community.

A report by the National Academy of Sciences’ National Research Council found that people exposed to the maximum allowed level of fluoride in tap water may be at greater risk for tooth decay and bone fractures. It urged the U.S. Environmental Protection Agency to reassess the risk posed by fluoride contamination to establish new guidelines, but did not indicate a better limit.

Juneau fluoridates only to about a quarter of the EPA’s limit, city officials say, and the study did not discuss the effects of the compound at that level. Municipal water fluoridation at that level is common nationwide as a method of preventing tooth decay.

The chairman of a city commission devoted to recommending action on fluoridation said the report does not seem to discredit fluoridation at lower levels, but others said it is reason for review.

“It is ironic, isn’t it?” Juneau Fluoride Study Commission member Emily Kane said. “Now it is time to reconvene and make a decision based on the findings of our country’s top scientists.”

The Juneau Water Utility resumed fluoridation of the areawide water system Wednesday after fixing a pump failure that had shut it down in November. Previously some had called for a halt to fluoridation on health grounds.

“We (the commission) agreed we would be guided by the academy’s findings,” Kane said. “Now some may realize this is not the greatest thing since sliced bread.”

The six fluoride commission members will meet April 3. But Chairman Bart Rozell said the report’s findings may be of little use in Juneau’s debate.

“The researchers studied fluoride levels much higher than what the city has reported in their system,” Rozell said.

“We need to talk to the city’s water department to determine what amount of fluoride is naturally occurring,” he said. “We have been aware that high levels are a risk to health, but believe it doesn’t rise to the level of the EPA standard, which was shown to be harmful.”

City officials say the level of naturally occurring fluoride in Southeast Alaska is negligible.

Mayor Bruce Botelho’s appointed commission was charged with making recommendations to the mayor, city manager and Juneau Assembly regarding the use of dental fluoride in drinking water. Four members have stated that the city should continue fluoridation in the immediate future, while Kane and Jamie Bursell have said the city should cease fluoride operations until reviewing the study.

The report indicated that children and infants are at a higher risk, because relative to their weight they are exposed to three to four times more fluoride than adults.

“I have said that I would not recommend the city stop with the information that I have seen in the past,” Deborah Erickson said. “I will just say I am looking forward to seeing the report.”

Excess fluoride enters some water supplies from runoff and industrial discharges. The academy’s expert panel said some 200,000 people in the United States may consume water that is at or above the government’s standard because of naturally occurring fluoride.

Children exposed to the government’s current maximum fluoride limit risk developing severe tooth enamel fluorosis, a condition characterized by discoloration, enamel loss and pitting of the teeth, the academy said in a statement.

“Naturally occurring fluoride is not seen as an issue in Juneau, or in the Southeast (Alaska),” said Carrie McMullen, an environmental program specialist with the state drinking water program. “The city has monitored the water daily and I have seen no significant fluoride spikes in the five years that I have been here.

“The drinking water meets all state and federal regulations.”

Alaska is a primacy state, which means it can exercise regulatory control of all federal rules affecting public water systems, McMullen said.

“Alaska water regulations are as stringent, or more so, than the federal government,” she said.

The report does not examine risks or benefits from the city-fluoridated water that millions of Americans drink, which contains about one-fourth the government’s limit. The EPA allows up to 4 milligrams of fluoride per liter of drinking water.

“During fluoridation normal fluoride levels in the Juneau system are between 0.7 and 1.2 milligrams per liter,” Juneau Water Utility Superintendent Grant Ritter said. “We recently measured at Last Chance Basin and the background was either nothing or 0.2, which is negligible.”

The city stopped fluoridation without notice in June 2003 to study its effects on copper leaching from pipes into the drinking water. Since then city officials have worked with state and federal agencies in establishing new copper levels at the Mendenhall water treatment plant because they found the old requirements unreasonably restrictive. The city resumed fluoridation in March 2004.

“People at different ages will retain a certain amount of fluoride buildup,” Ritter said. “Nobody knows how much they ingest in a day, which creates a problem.”

The Assembly would be happy to have some definitive results, Assembly member Jonathan Anderson said. Members are looking for some consensus by the commission, he said.

“What we need is something solid either way,” Anderson said. “Otherwise it is just thrown back in our laps.”

It is still not clear what legal responsibility the city may have, Kane said. That may leave the city in a difficult position.

“If we turn it off people may think they can sue for their children’s dental bills,” Kane said. “If we don’t, people may think they can sue for many other damages – if they knew this was bad for the population’s health and did nothing for it.”