METHUEN — Mayor Sharon M. Pollard wants the Board of Health to rescind its vote to fluoridate the town’s drinking water, saying the decision was made without properly informing the public.

Few people even knew of the vote until more than a week after it happened, a delay that angered the mayor, councilors and fluoridation opponents.

Fluoride won’t actually be added for some time — opponents have 90 days to gather signatures to force a referendum to stop it. But Board of Health Chairman Dante Santone is already in discussions with the state about the process.

He planned yesterday to respond to Pollard’s request that the board rescind its vote; a request she had police hand-deliver. Santone said his written response will defend the decision and decline to reverse it, at least for the time being.

Fluoride has been added to water supplies across the country for more than 50 years — including much of the Merrimack Valley — with the world’s dental and medical establishments recommending it as a way to help prevent tooth decay. Opponents argue it violates their freedom of choice and can cause a variety of medical problems. Referendums rejected fluoridating Methuen’s water in 1981 and again, narrowly, in 1997.

Pollard said the debate over fluoridation has been overshadowed by the way the vote occurred. It was taken May 29 in front of a roomful of supporters, but without giving opponents or town officials any notice other than a vague mention on the agenda.

“The issue isn’t the merits of fluoridating the water. The issue is that it looks to me like it was a calculated effort on the part of the board to invite (people who would) tell them why they should do it, and they sought no input from the city, never talked to the mayor about it, never talked to (any public works or water management officials) about it,” she said. “It was done in the dark, and that’s not the way things are done in the city of Methuen.”

While the board isn’t technically required to go out of its way to inform Town Hall of such a move, Pollard said Health Department Director Dr. Robert Katz has different responsibilities as a town employee. He resigned and his last day was yesterday, ending two-plus years with the town and nearly two decades as a public health director with three communities.

Neither Pollard nor Katz would say the move was forced, and Katz said he was already considering the new early retirement package passed by the Legislature several weeks ago. But both people indicated the fluoride flap accelerated Katz’s decision.

“He understands I wish he would’ve (told us about the vote in advance,)” Pollard said.

Katz called the decision “a personal matter,” and said in hindsight he probably should have informed the mayor of a potential vote.

“I don’t think there was any intent to deceive anybody,” said Katz, a dentist. “My problem is I tried to keep myself so disengaged and tried to maintain such a neutral position, I didn’t look at any other perspectives of it.”

As for the Board of Health, the mayor appoints members to three-year terms but it has independent decision-making power on public health issues. Pollard said board member Mary Ruth A. Robie is due for reappointment now and Santone in January, but would not comment on their futures.

“We’ve been this route with the board before, with (its decision to ban smoking from restaurants),” Pollard said. “I happen to agree with what the board did on smoking, but you can’t just railroad the people.”

Santone insists the board did nothing wrong, with members unable to “comprehend why it’s such a hot topic.” He said they did everything legally required, and assumed opponents would ask if they wanted to know if a vote was imminent.

But Town Council Chairman William M. Manzi III, who initially told one resident the vote didn’t happen — “I told them, ‘No, no, I would know about that,” he said — also believes it was intentionally kept quiet.

“There’s no question about it,” he said. Manzi hopes to strike a deal similar to that in 1997, when it was agreed there would be a voluntary, nonbinding referendum both sides would obey rather than a formal collection of signatures.

“I’m not personally comfortable (adding fluoridation) until that referendum has been reversed,” Manzi said.

William J. Patenaude helped lead the 1997 opposition effort, and hopes to repeat that success. He claims he asked Santone about a possible fluoridation vote a month ago and was told “it’s not on the radar screen,” which Santone denies saying.

Patenaude, who narrowly lost to Pollard in the last mayoral race, opposes fluoridation on freedom of choice grounds but also believes it is harmful. He said 10 people have volunteered so far to gather the roughly 2,700 signatures needed to get a referendum on the ballot.

Dr. Joseph Kalil, meanwhile, will be rooting against them. The local dentist has spent 20 years pushing fluoridation in Methuen, and “came home and celebrated” the night of the vote. He said the 1997 Board of Health “didn’t have the guts” to ignore the referendum in 1997, and the public health issue behind the fluoride debate “overrides any voting issue.”

Pollard said the town would need to build an addition onto the plant that treats the town’s Merrimack River water supply, and the whole process could cost $100,000. But Mary Foley, Director of the state Office of Oral Health, said the state would cover the cost of equipment, installation, construction and the first year of chemical supplies.