Water is essential for the human body to function properly which is why so much importance is given to water supply and water quality. Surface waters and groundwater are the main sources used to provide tap water, or municipal water, to the public. Tap water is treated to ensure compliance with about 60 microbiological, physico-chemical, radiological and organoleptic parameters described in European regulations which are transposed into national law. The extent of water treatment depends on the quality of the resource with the aim of eliminating pathogenic microorganisms such as bacteria, viruses, and parasites, chemical contaminants including for example pesticides and nitrates, and excess mineral salts like fluoride and sodium, among others. See ANSES’s work on this topic.