Opponents of fluoridated water opened a new front in their campaign Monday, urging the Healdsburg City Council to put warning labels in utility bills advising residents not to mix city water with baby formula for infants under 6 months old.

The activists said that according to the Centers For Disease Control and Prevention, it may increase the chances for dental fluorosis, or mottling of tooth enamel.

"Fluoride is a drug. A warning label needs to be on there," said Dawna Gallagher-Stroeh, who presented the City Council with a petition signed by 118 Healdsburg residents requesting the warning labels be inserted in city water bills

She was immediately answered by fluoride proponent Anthony Fernandez, a Santa Rosa dentist, who told the council thousands of people live in cities with natural amounts fluoride in the water and "they don't have restrictions."

The latest salvo in the fluoride battle came as the City Council discussed which council member should write the argument against a November ballot measure that proposes to stop fluoridation of the city's water, a practice that has gone on since 1952 in Healdsburg as a method to reduce dental decay.

The council put off the matter until Mayor Jim Wood, a retired dentist and defender of fluoridation of the city's water, returns from vacation.

Fernandez, chair of the fluoridation issue for the Redwood Empire Dental Society, acknowledged Monday that fluorosis, what he described as mottled spots on the teeth, can occur with high amounts of fluoride. But overall, he maintains Healdsburg's adding less than one part per million greatly benefits the population and reduces the rate of cavities by 25 percent to 30 percent.

Fernandez did however apologize for calling fluoride opponents "public health terrorists" in an earlier interview.

"They're not evil. They really believe this stuff," he said of the claims by critics that fluoride is toxic or poisonous.

He said Gallagher-Stroeh, the former Rohnert Park councilwoman who spearheaded the voter signature drive to get the fluoride issue before Healdsburg voters, "has always been polite to me to me . . . I believe her intentions are good."

The City Council two weeks ago agreed to placed the initiative on the Nov.4 ballot after anti-fluoride activists gathered 867 valid Healdsburg voter signatures, well over the approximate 600 needed — 10 percent of registered voters — to require a vote on the issue.

Healdsburg is the only city in Sonoma County that adds fluoride to its water, but the Sonoma County Water Agency has been studying whether to fluoridate its water, which is delivered to Santa Rosa, Petaluma, Rohnert Park, Cotati, Windsor, Sonoma, Valley of the Moon and Marin County.

The city councils of Cotati and Sebastopol have opposed fluoridation of the county's drinking water, even though Sebastopol has its own water supply that would not be affected directly by the county Water Agency proposal.

The Healdsburg system, which also provides water to adjacent Fitch Mountain, spends about $40,000 annually on fluoridation, according to Ryan Kirchner, the city's operations and utilities superintendent.

He said Healdsburg carefully monitors the fluoridation to ensure it falls within state department of Public Health guidelines.

You can reach Staff Writer Clark Mason at 521-5214 or clark.mason@pressdemocrat.com