Counties and municipalities, after fluoridating their water supplies for decades, are seeking to get rid of the chemical meant to prevent tooth cavities.

Already, Philomath, Ore.; Pinellas County, Fla., and Myerstown, Pa., have stopped adding fluoride to drinking water since May over health concerns.

Madison, a sprawling city in central Alabama, may reduce its fluoride by nearly 40 percent if county commissioners vote to ban the chemical during an expected Monday vote.

Fluoride is in many ways a toxin, Ben Gremillion, a Madison, Ala. resident, told his utility board, according to The Huntsville Times. It's not necessary for water quality. You can't boil it away.

More than 195 million Americans drink water with added fluoride, a chemical meant to prevent cavities. Individual counties and states regulate its addition. Federal health authorities recommend additional fluoride in drinking water, though no mandate exists. Within the last year, several counties stopped the addition or have voted to do so coming in the near future.

Most people don't notice the tasteless, odorless chemical, but some residents say they don't want the government making their health decisions.

You don't have the right to put it in the water, Jim Pruitt, a Pinellas County resident, told The St. Petersburg Times. You don't have the right to medicate us.

Pruitt spent $1,500 on a filtration system to remove fluoride because he doesn't trust the so-called scientists who don't really know what they are talking about, according to the Times.

The process of adding fluoride to drinking water began in Grand Rapids, Mich., in 1945.

While fluoride is toxic in high quantities, the amount in drinking water is not nearly enough to cause harm, according to the Centers for Disease Control and Prevention.

The recommended level of fluoride in drinking water is 1.2 milligrams per liter - the equivalent of half of a snowflake in a quart of water. You'd have to drink 10,000-20,000 glasses of water per day in order for fluoride to be toxic, according to the American Dental Association.

Adding fluoride to water is no different than fortifying milk with vitamin D, table salt with iodine, and bread and cereals with folic acid, according to the ADA.

The only potential negative effect of fluoride at the recommended level is dental fluorosis, a harmless discoloring of teeth that occurs from overexposure between the ages of 3 months and 8 years old, according to the CDC.

Anti-fluoride activitists say the levels of fluoride in drinking water can cause damage to the brain, thyroid and other organs.

Fluoride, the active ingredient in many pesticides and rodenticides, is a powerful poison - more acutely poisonous than lead, the Fluoride Action Network, a nonprofit organization that lobbies against the addition of fluoride, says on its website.

Fluoride's ability to damage the brain represents one of the most active areas of research on fluoride toxicity today, the group said on its website.

The CDC, however, not only maintains that fluoride is safe, but called water fluoridation one of the 10 greatest public health achievements of the 20th century. The ADA called fluorination the single most effective public health measure to prevent tooth decay.

Not all communities are trying to reduce fluoride levels. A bill in the New Jersey Legislature would require all public water systems in the state to add fluoride. Only 14 percent of people in New Jersey currently receive fluoridated water, according to the CDC. Hawaii is the only state that provides less fluoridated water.

People against the bill are citing the same risks that caused other counties to stop water fluoridation.

They are medicating us without our consent, and it's unethical and illegal, Jennifer DiOrio, a New Jersey high school teacher, told The New York Times.

But false information spreads easily, according to Barbara Gooch, associate director for science in the Oral Health Division of the CDC.

In the age of the Internet, it's very easy to spread many of these rumors, she told The New York Times. People go looking for information about why this is bad, and they find it pretty easily.