A STUDY OF WATER-BORNE ENDEMIC FLUOROSIS IN CHINA

Survey results are presented from 34 sentinel sites in 18 counties in endemic water-borne fluorosis areas of China through the years of 1991 and 1992. The progress in improving water to control fluorosis was ve ry slow, fly the end of 1991, only 42.1% of the villages, and 39.3% of the population, in endemic fluorosis areas had improved water supplie s. In 1992 this improvement increased by only 1%. Inspection of 987 wa ter improvement projects to reduce fluoride showed that 82.7% were con tinuously used; 10.3% had interrupted use, and 7.0% had been stopped o r destroyed. The projects resulted in 65.4% having a water fluoride co ntent of less than 1.0 mg/L, 21.3% had 1.0 - 1.5 mg/L, and 15.4% had m ore than 1.5 mg/L. In 34 sentinel sites, urinary fluoride content and dental fluorosis indices of 8-12 year old children decreased year by y ear, especially in the sites with longer water improvement and water f luoride content less than 1.0 mg/L. Symptoms and signs of adult fluoro sis also decreased, but not as significantly as the urinary fluoride c ontent and dental fluorosis of children.