[The use of fluoride from the viewpoint of toxicology and ecology]

Although the effectiveness of fluoride against dental caries seems to be established, criticism about its safety has never ceased. Its dual role as a (potentially beneficial) drug as well as a (potentially malignant) environmental pollutant have contributed to this controversy. Although Belgium does not allow the fluoridation of drinking water, many sources of air and water contamination exist due to industrial activities. The role of the dentist is to know about these regional fluoride sources when prescribing fluoride for caries control in order to obtain an optimal effect together with maximum safety.