CLEARWATER – After years of on-again, off-again discussion and debate, Pinellas County will begin fluoridating its water supply on Monday, ending its status as the largest water system in the eastern United States devoid of the cavity- fighting additive.

The move is lauded by county health officials and other medical professionals as a long-awaited and huge step toward preventing tooth decay, particularly in children.

It’s also a move condemned by a few impassioned critics who sharply question fluoride‘s effectiveness and safety and argue its use should be a matter of personal choice.

Only about a third of the county’s nearly 1 million residents – those living in St. Petersburg, Dunedin, Belleair, Gulfport and most of Oldsmar – now receive fluoridated water.

The county water system serves more than 600,000 residents in unincorporated areas plus Largo, Kenneth City, the beach communities, Clearwater, Tarpon Springs, Pinellas Park, Safety Harbor and part of Oldsmar.

The county will add 0.4 parts per million of fluoride to the drinking water. That will combine with naturally occurring fluoride in the water at 0.4 parts per million to reach what officials call the “optimum” level of 0.8 parts per million, based on the area’s climate.

Customers won’t be able to see, taste or smell the additive when it begins flowing through their taps shortly after 10 a.m. Monday, officials said. Fluoride is safe for fish and other pets, they said.

The cost of fluoridation is pennies per customer and will not require a water rate increase, said Pick Talley, the county’s utilities director.

The county is spending $600,000 on the fluoridation system and another $115,000 a year to add the substance to the drinking water. It will absorb those costs by spreading them out over 20 years, Talley said.

Cities across the nation have been adding fluoride, often called one of the most important medical advances of the past 50 years, to water supplies since it was introduced in Grand Rapids, Mich., in 1945. At the time, it was discovered that children whose drinking water was naturally fluoridated had stronger, healthier teeth than children who drank nonfluoridated water.

By 1960, tooth decay rates in Grand Rapids decreased by 56 percent, the Pinellas Health Department says.

In Florida, cities have been fluoridating water systems since Gainesville did it in the late 1940s. About 63 percent of the residents on community water systems in the state drink fluoridated water. Nationally, the figure is about 66 percent.

More than a half-century later, the argument over fluoridation remains contentious. Yet Pinellas, for the most part, has managed to avoid the teeth-gnashing that has accompanied the issue elsewhere.

That’s because, until recently, there was little public interest in fluoridating the county’s water supply, Talley said.

However, opinion surveys conducted in the past few years have shown that a majority of respondents want fluoride in their water, or at least the opportunity to vote on the issue. Pinellas has never held a referendum on fluoridation.

The most recent survey was done in 2002. Of 737 Pinellas water customers polled, nearly 52 percent favored fluoridation. Another 36 percent were undecided and 12 percent were opposed, with 4 percent citing health reasons.

In 1999, a survey of 500 residents commissioned by state and local dental associations found that more than 70 percent of those served by nonfluoridated water supplies favored a referendum to add the substance to their drinking water.

Fluoride Passes 6-1

After years of inaction, county commissioners finally sank their teeth into fluoride in August when they held a public workshop and heard from nearly 30 people on both sides of the issue.

Two weeks later, commissioners voted 6-1 in favor of fluoridation. The move was recommended by Pinellas health department Director John P. Heilman and supported by a number of dentists and other health professionals.

Since then, fluoride-related telephone calls to the utilities department are running 65 percent in favor and 36 percent against, statistics show.

Health department officials said they’ve seen a 40 percent reduction in tooth decay in 15- year-olds who live in St. Petersburg since the city began fluoridating its water in 1992.

“This sort of a program can have a huge impact on the lives of kids whose unsightly mouths make them social outcasts in school,” Heilman said.

Longtime Commissioner Barbara Sheen Todd, who cast the lone vote against fluoridation, said she isn’t convinced the type of fluoride the county is using is safe.

The substance, called fluorosilicic acid, is a byproduct of phosphate fertilizer production and contains traces of arsenic, lead and other contaminants, critics charge.

That’s true, said Bob Powell, director of Pinellas utilities’ laboratory department. Yet he said when fluorosilicic acid is broken down in water, the contaminants are diluted to undetectable levels that pose no harm to public health.

“When you figure that we’re only going to be adding less than three gallons of concentrated product to a million gallons of water, you’re really looking at levels that are so low we won’t even be able to pick it up on our equipment,” Powell said.

St. Petersburg and Tampa also use fluorosilicic acid, as do most other large fluoridated water systems in Florida and elsewhere in the country, he said.

“We’ve been applying [fluoride] literally to millions and millions of people for decades,” Powell said. “If any of these things that were supposedly such imminent health effects were true, we’d be seeing it. And we just aren’t.”

Toxicological Risks Under Review

Nonetheless, Todd wanted to delay a decision pending the completion of ongoing federal studies and reviews, including one on the toxicological risk of fluoride in drinking water, to be completed in November.

That review by the National Research Council, part of the National Academy of Sciences, calls for examining published data since 1993 and assessing information on fluoride intake from drinking water, dental products such as toothpaste, food and beverages. The review includes re-evaluating federal maximum contaminant levels for fluoride in drinking water.

“I just felt that there were too many issues that had been raised that ought to be addressed before the board moved ahead on it,” said Todd, adding that she plans to install a filtration system in her home, in unincorporated St. Petersburg.

Although the issue was decided 10 months ago, commissioners continue to weather a barrage of criticism from a small but vocal group of fluoride foes at their biweekly meetings and in dozens of letters, phone calls and e-mails.

“We will not stop until the spigot is turned off,” Peter Glickman, president of Citizens for Safe Water, a political action committee, told commissioners last month.

Besides raising concerns about fluorosilicic acid, opponents argue that residents should have been allowed to decide the issue at the polls – and should not be forced to accept something they do not want, or do not even know they will get.

Critics also point out that too much fluoride can cause dental fluorosis in children, a condition in which teeth become discolored.

In addition to getting fluoride from water, children may get fluoride from beverages or packaged foods that are made with fluoridated water. Swallowing fluoridated toothpaste also can contribute to fluorosis, which usually appears in children by age 6.

To prevent fluorosis, officials recommend that prescription dietary fluoride supplements should not be given to children who live or attend school in a community with fluoridated water.

“I just can’t find any evidence that there’s anything wrong with doing it, that it would cause harm,” commission Chairwoman Susan Latvala said. “I think there’s some erroneous information that is out there and is being passed around. And people are fearful because they read it and believe it.”

Reporter Carlos Moncada can be reached at (727) 823-3412.