AUGUSTA – Public health advocates turned out en masse in Augusta on Monday to defend the practice of adding fluoride to public drinking water supplies. The press conference came in response to a flurry of recent challenges to fluoridation in Maine.

Speakers at the event took aim at a Bangor pediatrician who has asked the city to cease fluoridation as well as at the water utility in the Hancock County town of Mount Desert, where voters decided earlier this month to discontinue the practice.

Beginning in the 1950s, fluoride has been added to many public water supplies across the country to help protect against tooth decay, especially in children. Critics have protested the practice on grounds ranging from fears of a communist plot to allegations that fluoride consumption is linked to autism, cancer and other health conditions.

By Maine law, fluoridation can begin only with the support of local voters, and once it’s in place, only voters may decide to discontinue it. About half of Maine’s 150 public water utilities now add fluoride, which is strictly controlled to reach the accepted therapeutic level of 1.2 parts per million. Bangor water has been fluoridated since 1967.

Speaking to a small group of reporters, Dr. Dora Anne Mills, director of the Maine Center for Disease Control and Prevention, said recent challenges to the well-established practice of adding fluoride to public water are irresponsible and based on “misinformation.” She said health officials are concerned that public acceptance of fluoridation will be undermined by inaccurate claims of its potential health risks.

“Fear is a contagion,” she said.

Mills pointed out that the federal CDC has called public water fluoridation “one of the 10 most successful public health achievements of the 20th century” because of its positive effect on the dental health of children.

“Tooth decay is the most common chronic disease among children” and can lead to a lifetime of ill health and social dysfunction, Mills said. Fluoride has demonstrated its effectiveness in reducing the rate of dental disease, she said, and is an important tool for improving children’s health, fully endorsed by a long list of medical, dental, public health and other groups.

At least 19 others spoke in support of fluoridation at Monday’s press event, including lawmakers, pediatricians, dentists and lawmakers.

Bangor dentist and children’s health advocate Jonathan Shenkin said that an opinion piece by pediatrician Leonardo Leonidas that ran in the Bangor Daily News on Saturday was “heinous” in its inaccuracy and distortion. He said Leonidas “appears to be the only [pediatrician] in the nation fighting fluoridation.”

Dr. Donald Burgess, president of the Maine Chapter of the American Academy of Pediatrics, said Leonidas’ opinion piece presented “scientifically inappropriate and irresponsible” information not endorsed by the AAP.

Leonidas wrote that studies have demonstrated a link between elevated levels of fluoride and lowered intelligence, autism, bone strength and cancer. A recent advisory from the American Dental Association that infant formula should be mixed with nonfluoridated water in order to avoid staining tooth enamel should alarm health officials,” he wrote.

“If fluoride were safe for young children, the ADA would not reverse their 40-year policy of giving fluoride to infants,” he wrote.

On Monday, Leonidas said he isn’t bothered by high-decibel criticism of his position.

“That’s fine; I can handle it,” he said. “I’m in the right here.”

Leonidas stressed that he’s not opposed to prescribing fluoride for children at special risk for developing dental disease, but he does oppose dosing everyone who drinks public water. The AAP and other health groups, he charged, are being too slow to respond to growing evidence of fluoride’s health risks.

Paul Slack at the Mount Desert Water District said he has no regrets about campaigning to rid his water system of fluoride. Participants in the annual town meeting decided earlier this month to discontinue fluoridation by a vote of 229-42.

Slack said he took the initiative as he began to hear more about the risks of fluoride.

“We decided we could no longer justify the risks associated with having it in the water,” he said.

Slack, who was criticized at Monday’s media event for providing only anti-fluoride information to voters, said his materials referred interested people to the Web site of the American Dental Association, a strong advocate of fluoridation.

“People were certainly capable of looking up the information themselves,” he said Monday.

The utility will pull the plug on its fluoride pump on Friday, Slack said.

Last fall, voters in Jackman defeated a water district-initiated proposal to discontinue fluoridation. In Lincoln, residents voted not to start.

Rep. Elizabeth Miller, D-Somerville, said at the news conference that if Maine communities dump fluoride, their children would suffer. In a state where dental care for low-income families is already hard to come by, she said, fluoride extends basic protection where it’s needed most.

“We need more communities with fluoride, not less,” she said. Miller said the recent attacks on fluoridation would prompt her and other lawmakers to explore ways to expand it to more communities, including the possibility of mandating the fluoridation of all public water supplies.

In response to Leonidas’ concern, the Bangor Water District has provided information about fluoride treatment to the City Council. Board members are expected to present a statement of support for the fluoridation program at the council’s next meeting on Monday, March 26.