Water fluoridation in the United States is common amongst most states. As of May , 42 of the 50 largest U. On January 25, , Grand Rapids, Michigan , became the first community in the United States to fluoridate its drinking water for the intended purpose of helping to prevent tooth decay. Fluoridation became an official policy of the U. Public Health Service by , and by water fluoridation had become widely used in the U. Those included the 3. Community water fluoridation in the United States is partly due to the research of Dr.
Frederick McKay, who pressed the dental community for an investigation into what was then known as "Colorado Brown Stain. McKay, All the affected children were from the Pikes Peak region. Despite the negative impact on the physical appearance of their teeth, the children with stained, mottled and pitted teeth also had fewer cavities than other children.
McKay brought this to the attention of Greene Vardiman Black , and Black's interest was followed by greater interest within the dental profession. Initial hypotheses for the staining included poor nutrition, overconsumption of pork or milk, radium exposure, childhood diseases , or a [calcium] deficiency in the local drinking water. As the rain and snow fell, the resulting runoff water dissolved fluoride which made its way into the water supply.
Dental and aluminum researchers then moved toward determining a relatively safe level of fluoride to be added to water supplies. The research had two goals: 1 to warn communities with a high concentration of fluoride of the danger, initiating a reduction of the fluoride levels in order to reduce incidence rates of fluorosis, and 2 to encourage communities with a low concentration of fluoride in drinking water to add fluoride in order to help prevent tooth decay.
By , In April , fluoride levels in the United States were lowered for the first time in 50 years to the minimum recommended level of 0. This decision was based on the results of two national surveys β NHANES which assessed the prevalence of dental fluorosis, and found that two out of five adolescents had tooth streaking or spottiness on their teeth - an increase of mostly very mild or mild forms. On September 24, , a federal judge ordered the U. Environmental Protection Agency EPA to take regulatory action citing the findings of an extensive federal review of many studies published in peer-reviewed scientific and medical journals showing a dosage-dependent negative impact on children's IQs.
