A practice that most North Carolinians do without thinking much about it – drinking fluoridated water from local systems – has become a controversial topic in parts of the Triangle.

On Thursday, the Orange County Water and Sewer Authority will hear petitions from citizens who want the county to stop fluoridating public water. And in Durham on Thursday, Board of Health directors will hear from a subcommittee that was asked to look into the issue.

Fluoride opponents point to a book, “The Case Against Fluoride,” to support their argument that fluoridating drinking water amounts to adding hazardous waste to the public water supply. They say fluoride is potentially hazardous to human health and is not as beneficial in preventing tooth decay as once thought.

Nearly 90 percent of North Carolina residents who drink from local water systems drink fluoridated water. It has been standard practice in most North Carolina counties for 50 years.

But after some Durham residents complained, the county’s Board of Health assembled a subcommittee in March “to evaluate the addition of fluoride to city drinking water and come back with a recommendation,” said Vicki Westbrook, the city’s assistant director of water management. The board is expected to hear the subcommittee’s recommendation at a meeting Thursday.

Corey Sturmer, a Durham citizen who opposes water fluoridation practices, said he and other activists have been unsuccessful in bringing the issue to the attention of Raleigh officials.

“Raleigh, unfortunately, has been provided with copious amounts of scientific data, repeated appearances by myself and other citizens and even notifications that what they are doing breaks current state and federal drug laws,” Sturmer said.

Efforts to reach Raleigh’s assistant director of public utilities were unsuccessful, but a page on the City of Raleigh website indicates its continued support of current fluoridation practices.

“The US Centers for Disease Control and Prevention (CDC), US Department of Health and Human Services (HHS), NC Division of Public Health and other health organizations recommend fluoridation of drinking water at the appropriate level to help prevent tooth decay,” the page reads.

Sturmer contends that because Raleigh, Durham and Chapel Hill add fluoride to water, it should be considered a “medication.” “The problem is, you need to have a doctor’s license to prescribe medication to prevent a disease,” he said.

But Dr. Gary Slade, professor and director of the Oral Epidemiology PhD program at the UNC School of Dentistry, disagreed that fluoride is “medicine.”

“Fluoride occurs naturally in water,” Slade said Wednesday. “It always has. This is not the same as putting pills in the water supply or taking a medication,. This is adjusting a naturally occurring phenomenon.”

Slade, who recently co-authored an Australian study that concluded that adding fluoride to drinking water reduces tooth decay in adult men and women (and not just in children), said that there is no known scientific evidence linking controlled amounts of fluoride with adverse health effects in humans.

“If Orange County was to remove fluoride from the drinking water, that would mean that a bunch of people would have no choice in a certain aspect of their health because it’s pretty much impossible to buy bottled fluoridated water,” Slade said.

“I can understand if people don’t want to drink fluoridated water, but there’s an important difference here because they actually do have a choice. Someone can currently buy bottled water without fluoride, or they can put a filter on that is able to remove fluoride,” he added. “If fluoride is taken out of the water, the opposite does not apply.”

The issue of fluoride in water has popped up in other areas of the nation. Last month, voters in Portland, Ore., voted 60 percent to 40 percent against adding fluoride to the city’s water.

San Jose, Calif., doesn’t have fluoride in its water now, but is working to add it. When it does, Portland will be the largest city in the United States without fluoridated water.