GRAND RAPIDS — Will the city that became the first in the world to fluoridate its drinking water decide to discontinue use of the chemical?

Grand Rapids has been fluoridating its tap water since 1945, but now some city officials say they’re studying the question because of increased concerns over the potential long-term effects of exposure to what some consider a toxic chemical.

Corky Overmyer, the city’s director of sustainability, said officials are working with scientists at Grand Valley State University and other water quality specialists to determine whether to continue adding fluoride to the city’s water supply.

“Because we’re trying to eliminate toxins in our community, I thought we should study this issue,” Overmyer said Tuesday during Brownfields 2008, a national redevelopment conference being held in Detroit.

Mayor George Heartwell, who cites fluoridation when he boasts of Grand Rapids’ progressive history, said he will need to be convinced.

“We’re surely not considering dropping the fluoride from our water,” he said. “We would not do that without really hard scientific evidence.”

The West Michigan Dental Society also would need to be convinced, said chapter president Doug Killian.

Killian, who practices in the rural community of Mecosta north of Grand Rapids, said he sees the evidence in his dental chair every day.

“The rate of tooth decay in this area is generally higher than areas where there is access to (fluoridated) city water,” he said. “It’s been well documented and well proven.”

Overmyer said he’s been receiving “a lot of flak” and information from anti-fluoridation advocates.

“I said, ‘What if this is true?'” Overmyer said.

He said the process of evaluating whether the city would discontinue fluoridation will take time.

The Centers for Disease Control and Prevention calls fluoridation safe and effective for preventing tooth decay and identified the process as one of the 10 great health advancements of the 20th century.

Opponents of fluoridation have said the chemical can be toxic, and some evidence shows it might cause weak bones, thyroid problems, bone cancer and other problems. Malfunctioning fluoridation systems in some cities have poisoned residents, they contend.

Grand Rapids became the first community in the world to utilize the process in an effort to improve dental health in 1945. Today, the city’s system provides fluoridated water to the city and 11 other suburban communities.

Last year, the city commemorated its role as a fluoridation pioneer by dedicating a new riverfront monument and drinking fountain dispensing fluoridated water near the JW Marriott hotel.

— Press staff writer Jim Harger contributed to this story.