The role of fluoride in dental caries prevention is well-documented. However, excessive fluoride exposure may have detrimental effects on human health. The first overt sign of chronic fluoride overdose is enamel fluorosis. The increasing prevalence of this condition has been observed recently due to widespread use of water fluoridation, dental cavity prevention products, and environmental pollution. Our review provides basic information regarding the sources of fluoride exposure in Poland, with special attention to drinking water as well as current Polish and European Union legislation on drinking water quality. The notion of infant formula reconstituted in fluoridated water as a risk factor for enamel fluorosis development is discussed. The implications of setting the upper limit of fluoride content in the drinking water at 1.5 mg/l were mentioned. The need for increasing knowledge about adverse effects of fluoride as well as the availability of data on fluoride content in the environment is emphasized.