[Fluoride levels in springs and water sources and in the public supply networks of municipalities in the State of Pernambuco, Brazil].

Fluoridation is considered an effective and wide-ranging measure in combatting dental caries. Despite being mandatory in Brazil since 1974, the implementation continues to be unequal throughout the country. The objective was to describe and analyze fluorine levels in the waters of the public supply grid of the 2nd macro region of the state of Pernambuco in municipalities with 50,000 inhabitants or more. This is a descriptive study based on a comparison of data from Pernambuco Sanitation Company (Compesa), the Vigifluor Project, the Water Quality Surveillance Information System for Human Consumption (Sisagua) the Brazilian Institute of Geography and Statistics (IBGE) and the National Sanitation Information System (SNIS), on the fluoridation of water in municipalities of the 2nd health macro region of Pernambuco. Although the municipalities studied do not have artificial fluoridation, significant levels of natural fluorine were found in the sources that supply the regions. However, these levels of fluorine do not remain constant in the waters of the supply network of the municipalities studied, therefore there is no effective prevention against caries. Artificial fluoridation is an effective measure in preventing caries and should therefore be expanded in regions that are not yet fluoridated.