ARCATA — About 30 Arcata residents gathered on the lawn of City Hall on Thursday in support of the proposed Safe Drinking Water ordinance, which apparently targets the city’s continued use of fluoride.

Citizens filed a notice of intent to circulate a petition to place the ordinance on a citywide ballot. The citizens plan to collect signatures — 15 percent of registered Arcata voters — and then approach the Arcata City Council with the ordinance. If the council does not pass the ordinance, then a special election could be held.

The proposed ordinance would prohibit the addition of any substance, which has not been approved by the Federal Drug Administration, to drinking water. The ordinance, however, does not specifically mention fluoride anywhere in its language.

Substances intended to treat humans, instead of the water itself, would be banned. The initiative would also prohibit adding substances containing contaminants that exceed maximum exposure levels to the water supply.

At a City Council meeting last month, the issue of repealing the city’s 50-year-old Fluoride Program was up for discussion. After a nearly three-hour debate, from those on both sides of the fluoride issue, the council ruled it should be up to the people to decide.

“This is all about safe water,” said Bruce LeBel of Arcata Citizens for Safe Drinking Water. “This is an ordinance everyone can agree on because it disallows the addition of non-FDA approved substances and contaminants. It’s quite simple. The FDA has not approved fluoride.” However, documents on the FDA’s website refer to the legal addition of fluoride to bottled drinking water.

A news release from the citizens group states, “To date, no manufacturer or supplier of fluoride has sought FDA approval in support of claims for health benefits from adding fluoride to drinking water.”

At the City Council meeting in June, conflicting studies of fluoride’s benefits and harms were raised.

“It boils down to belief systems,” LeBel said. “There’s a long history of research that has contradictory conclusions to it. The science is literally very, very mixed.”

LeBel likened the belief in fluoride’s benefits to the belief that Saddam Hussein was involved in the terrorist attacks of Sept. 11, 2001.

“If it’s repeated in society long enough then that mythology becomes a belief system,” he said.

Noel Hilliard said the proposed ordinance would not stop the addition of fluoride to the water if fluoride is approved by the FDA as reducing dental caries. Although the federal organization has approved fluoride’s topical uses, it has yet to approve fluoridated drinking water as a beneficial, harmless treatment in reducing dental decay, Hilliard said.

“There have been unsubstantiated health claims made for the last 50 years,” Hilliard said.

Dr. Ann Lindsay, Humboldt County public health officer, said she has met with the citizens several times, read several books they gave her and pointed out some scientific fallacies in these references.

“I want to reassure the public that I feel water fluoridation is safe, and many reliable professional organizations support it,” she said.

She said improving dental health of children has been one of the county’s public health priorities for several years, and fluoride is effective in reducing tooth decay.

Staff writer Sara Watson Arthurs contributed to this story.