Résumé
ObjectiveTo investigate the concentration of water fluoride and the application of water defluoridation projects in Suizhou,and to provide a basis for water improvement and prevention of the disease.MethodsCross-sectional study was carried out to investigate completely the water defluoridation projects built between 1986 and 2009 in the area under Suizhou's jurisdiction; 3 source water and terminal water samples of the projects in use were collected,respectively; 1 water sample was collected,respectively in the 3 projects with out-ofcommission or discarded water sources that used to be major water supply,for detection of fluoride,chloride,total hardness,heavy metals and other indicators.ResultsA total of 21 projects were investigated,14 projects were in normal use (66.7％),7 projects were out of order and abandoned (33.3％).Of the 14 projects normally used,13projects with water fluoride concentration ≤ 1.0 mg/L(92.9％)and 1 project with water fluoride concentration higher than 1.0 mg/L(7.1％),the concentration of water fluoride in the 7 abandoned projects was higher than 1.0 mg/L(100％).Arsenic and lead levels of all the water samples were normal.There were two water samples with iron content exceeded the standard,and one total hardness of water samples exceeded the standard in the normally used 14 peripheral water sources.One chloride content exceeded the standard,one manganese content exceeded the standard,two iron content exceeded the standard and three total hardness exceeded the standard in the seven abandoned projects.ConclusionsSome defluoridation projects are stopped using and abandoned in Suizhou,and the water fluoride exceeds the standard.