Fluoride in drinking water
Fluoridation of water is supported by many national and international organizations. The World Health Organizations, Centers for Disease Control and Prevention, Health Canada, and multiple dental associations, including the American, Canadian and provincial associations believe water fluoridation helps with dental problems. Health Canada has even declared water fluoridation a public health issue.
Some areas around the world already have high levels of fluorides in their soil and water sources. These areas include volcanic rich soils, igneous and metamorphic rock formations, and mountain ranges with high levels of marine sediment. Almost all water contains some naturally occurring fluoride, but usually at levels too low to prevent tooth decay. Many communities choose to adjust the fluoride concentration in the water supply to a level beneficial to reduce tooth decay and promote good oral health.
In Canada, Brantford, Ontario was the first community to fluoridate their water supply in 1945. Water treatment is the responsibility of the municipal governments but is regulated by federal and provincial governments. Therefore, communities across Canada have the choice of whether to fluoridate their water. As of 2009, 45% of Canadian residents have fluoridated water. Canada is one of the most fluoridated countries in the world. In comparison, only 5.7% of the world’s population has their public water supply fluoridated. The provinces with the highest rates of water fluoridation are Ontario, Alberta and Manitoba while the provinces with the lowest rates are British Columbia and Newfoundland. There is no fluoridation of drinking water in Yukon and Nunavut. In the United States, 72% of the population has access to fluoridated water. In Canada, fluoride levels are highly monitored. In 2007, an expert panel concluded that 0.7 ppm was the optimal level of water fluoridation without causing adverse effects.
Benefits of Water Fluoridation
When fluoride was added to the water in Brantford, Ontario in 1945 it was as a test of the benefits of water fluoridation, with Sarnia, Ontario being the comparative city without fluoridation. Researchers found a significant drop in the severity of cavities where water was fluoridated in Brantford compared to where it was not in Sarnia. It has been found that the health benefits of fluoride are fewer cavities and less severe cavities, less need for fillings and tooth extractions, and less pain and suffering associated with tooth decay. In fact, given the dramatic decline in tooth decay during the past 60 years, the Centers for Disease Control and Prevention (CDC) named water fluoridation one of Ten Great Public Health Interventions of the 20th Century.
Proponents of water fluoridation state that there is no risk to health when water fluoridation is monitored and remains at an appropriate concentration. The safety and effectiveness of fluoride at levels used in community water fluoridation has been thoroughly documented by scientific and public health organizations using scientific reviews and expert panels. Experts have weighed the findings and the quality of the available evidence and found that the weight of peer-reviewed scientific evidence does not support an association between water fluoridation and any adverse health effect or systemic disorders.
Supporters of water fluoridation state that it is important to have fluoride in drinking water in addition to the fluoride in toothpaste and fluoride treatments at the dentist’s office. The combined use of fluoride toothpaste and fluoridated water offers protection above using either separately. Toothpaste contains a higher concentration of fluoride but its effect wears off after an hour or two. Fluoride in drinking water is diluted, but it comes in contact with the teeth every time you drink tap water or beverages made from tap water, as well as foods prepared with tap water. This provides your teeth with a near continuous exposure to fluoride all day. Use of both fluoridated water and fluoridated toothpaste is recommended because fluoride in water and fluoride in toothpaste work differently to help prevent tooth decay. Water fluoridation is associated with an increased proportion of children without cavities and reduces the prevalence of tooth decay by 14.6% (2.25 teeth) compared to non-fluoridated areas. In Orillia, a town that has never fluoridated their water, elementary school children have the most severely decayed teeth among the 10 largest communities in Simcoe Muskoka, at a 66% higher decay rate than fluoridated areas in the region.
Proponents of water fluoridation agree that, of course, it does cost money to fluoridate the water but argue that the money is more than recouped in savings due to diminished tooth decay. A 2004 Canadian study concluded that every dollar invested in water fluoridation saves approximately $38 in dental treatment costs. Results from a Quebec study show the cost-effectiveness of water fluoridation even with the conservative estimation of a one percent decrease in cavities. Along the same lines, the United States Centers for Disease Control and Prevention found that the costs of restorative care to avert disease outweighed the cost of water fluoridation in towns of any size, even with the widespread availability of many forms of fluoride today. Under typical conditions, the annual per person cost savings in fluoridated communities is $16 in communities of fewer than 5,000 people and $19 dollars in communities of greater than 20,000 people. The lifetime cost of water fluoridation for one person is less than the cost of one dental filling.