This article, written by the American Ground Water Trust was originally published in



In the United States the question still remains regarding the cost/ benefits of adding fluoride to drinking water.  Well owners certainly have a choice about giving children additional fluoride.  For many millions of Americans with a water utility as their provider, the choice is made for them.


The first municipal program to add fluoride to drinking water started in 1945 in Grand Rapids, Michigan.  Today, approximately sixty percent of Americans drink fluoridated water from fluoridated public water systems.  The fluoride is added to public water supplies to achieve drinking water fluoride levels between 0.7 to 1.2 parts per million (ppm*).  These are the levels recommended by the American Dental Association to help prevent tooth decay.  In 1983, the U.S. Environmental Protection Agency set a concentration level of 4 ppm as the Maximum Contaminant Level (MCL) for fluoride in public drinking water supplies to prevent "skeletal fluorosis" (arthritic "brittle bone" disease).  A Secondary MCL was set at 2 ppm to prevent cosmetic "dental fluorosis" (observed as white spots or yellow and dark brown mottling of the teeth). 


The MCL is a legally enforceable level that public water utilities must follow.  The Secondary MCL is a guidance / advisory level that is not enforceable.  Neither level is enforceable for private wells or for water tests required for property transactions. Fluoride of geological origin is often found naturally in trace amounts (generally less than 0.3 ppm) in ground water. 


There has been on-going controversy during the last two decades concerning the effectiveness of fluoridation of water supplies in preventing tooth decay.  It seems that studies can be found that support both sides of the debate.  In the late eighties the National Institute of Dental Research concluded that fluoride has no effect on the incidence of tooth decay and that 66 percent of children in communities with fluoridated-public water suffer from dental fluorosis.  However, other researchers have found that fluoride does reduce the rate of tooth decay.  The American Dental Association recommends fluoride supplements for children from 6 months to 16 years old in non- or low-fluoridated communities.  In contrast, the Canadian Dental Association advises against fluoride supplements for children before their permanent teeth have erupted, at about 6 to 7 years of age, to avoid tooth discoloration.  The Center for Disease Control in Atlanta has stated, and many recent studies now seem to suggest, that topically applied fluoride is more effective in preventing tooth decay compared to ingestion of fluoride in food, drink or fluoride supplements. Virtually all places in Europe (93%) have banned fluoride as an addition to water supply because of the controversy surrounding its use. Europe's precautionary approach is to promote better dental hygiene.


A number of recent studies have indicated that fluoride may be associated with other health risks.  It may be a cause of hyperactivity, depressed IQ, elevated blood-lead levels in children, and is a possible carcinogen.   Fluoride is used in some pharmaceuticals (e.g., Prozac) and almost 200 pesticides.  Some retail beverages are prepared with fluoridated water, although the U.S. Federal Food and Drug Administration does not require the listing of fluoride in the ingredients label.


Some dentists recommend a laboratory water quality test of drinking water before prescribing a fluoride treatment plan.  For well owners, testing your water is a good idea whether or not the dentist recommends it.  Fluoride tests are not expensive. If you have high concentrations of fluoride in your water, water treatment devices are available.  Reverse osmosis is recognized as an effective way to reduce fluoride in water.  Activated alumina ion-exchange is also effective but requires a pH (acidity) value between 5.5 and 6.5 to reduce fluoride levels.  


*(ppm – parts per million is very similar to mg/L – milligrams per liter)


[© American Ground Water Trust.  This article may be reprinted for non-commercial educational purposes provided it is used in its entirety and that reference is made to its source as an article in THE AMERICAN WELL OWNER, 2001, Number 2]