NEW BEDFORD — Mayor Scott W. Lang has announced his opposition to fluoridating the city’s water supply, and will call for a binding referendum on the November ballot so voters can decide the issue.

“I am against introducing fluoride into the city’s water supply. I do not think the inherent risk to the population of fluoridation outweighs the public good,” the mayor said in a statement released yesterday.

Dr. Patricia Andrade, chairwoman of the New Bedford Board of Health, said the board’s support of fluoridation as a means to address chronic dental problems has not wavered. The board voted in February 2004 to fluoridate the city’s water supply, but that ruling has not been enacted.

“The Board of Health still feels citywide fluoridation is the best way to impact oral health,” she said. “In the predicament we are in now, with the mayor saying he does not support fluoridation, we have discussed the possibility of a binding referendum.”

She said the board supports a referendum and has contacted its legal counsel to pursue the matter.

The City Council previously has called for a referendum to decide the fluoridation issue. Mayor Lang said he would prefer the referendum be on the November ballot.

Councilor-at-large Brian K. Gomes, who proposed the referendum, applauded Mayor Lang’s stance.

“I commend Mayor Lang’s stance today that is in the best interests of all in the city,” he said. “The implementation of a program that will go out and reach out to kids is the right approach.” He said he worries that putting fluoride in the water might have a negative effect on the city’s senior citizens.

“Would they be getting an overabundance of fluoride when they drink their morning coffee?” he asked.

The board had agreed to fluoridate the water after a number of the city’s dentists and health professionals testified to the overall poor oral health of the city’s children. On more than one occasion, proponents of fluoride called the situation in New Bedford a “dental health crisis,” and said the city’s children have a higher-than-average incidence of tooth decay.

Mayor Lang, however, said that after holding three public hearings and listening to many people’s opinions on the issue, he made his decision.

“I believe that the issue of adolescent dental health and tooth decay can be addressed without mass medicating the entire population of our city,” he wrote.

He said the city, through the School Department and Health Department, will target the oral health of children by handing out toothbrushes, toothpaste and floss to children. In addition, fluoride rinse, pills, coating and drops will be provided to children with parental permission. He will also have the city coordinate with Greater New Bedford Regional Vocational-Technical High School, the Greater New Bedford Health Center and dentists to support the existing dental health treatment and education program.

Mayor Lang also announced he would ask the School Committee, which he chairs, to remove soda and all other unhealthy, sugary snacks from schools.

“I anticipate there will be a lively debate throughout the city prior to November to attempt to educate the voters pro or con on this issue,” he wrote.

New Bedford has a long and controversial history with fluoridation. The issue was hotly contested in New Bedford in the 1970s with lawsuits, public referendums and much debate. Conspiracy theorists believed fluoridation was a Communist plot to weaken Americans’ health, but health professionals were adamant that fluoride had significant and proven dental health benefits.

New Bedford voters approved a referendum in favor of fluoridation in 1973, but it took the city until 1978 to begin adding fluoride to the water.

Ronald A.J. DeMello, an activist who later ran for political office, launched a campaign to overturn the decision, and he successfully led a charge to stop fluoridating the city’s water. In a second referendum in 1979, voters said no to fluoridation by a 2-to-1 margin.

A group of 16 city residents and the American Dental Society sued the city to keep fluoride in the water, but a Superior Court judge ruled that the voters’ rejection of fluoridation should stand. On May 5, 1980, the supply of fluoride was cut off, less than two years after it began.

More recently, the New Bedford Board of Health approved fluoridation of the city’s water supply in February 2004, after holding a sparsely attended public hearing. In so doing, the board effectively overturned the judge’s ruling from 25 years before. State law gives local boards of health the authority to fluoridate public drinking water.

Under former Mayor Frederick M. Kalisz Jr., the city’s Water Department spent about $15,000 upgrading the existing fluoridation equipment at the city’s water treatment plant in Freetown. The staff also took extensive training from the state Department of Environmental Protection to learn how to handle the fluoride in its concentrated form.

But the tap for fluoride was never turned on, and Mayor Lang withheld his support until he heard from city residents.