Investigating the prevalent status on coal-burning pollution endemic fluorosis in some areas in northwestern Guizhou

Objective To seek the possible means of controlling endemic fluorosis by studying the prevalent status of endemic fluorosis in north-western Guizhou. Methods Assaied fluoride contents in coal, drinking water, corn, chili and tea, investigated the prevalence of dental fluorosis and fluorosis and fluoride levels in urine in the local inhabitants. Results Fluoride content in coal of Hualuo, Majiazhuang and Pianpozhai was 107.8, 104.1 and 117.6 mg/kg, respectively; in drinking water of the three village was 0.12, 0.14 and 0.05 mg/L, respectively; in corn of the three village was 30.6, 33.4 and 49.8 mg/kg, respectively; in chili of the three village was 513.2, 342.6 and 281.0 mg/kg, respectively. In Hualuo and Majiazhuang,the check out rates of dentel fluorosis were all over higher than 96.96%;and those of clinical skelatal fluorosis were 75.43% and 60.52%, respectively; and the urinary fluoride were 4.98 and 3.44 mg/L,respectively. Conclusions Fluoride levels in coal is relatively low in three investigated villages, and the higher fluoride contents are in the corn and chili,and fluorosis is very serious. The fluorine source is mainly from the clay used as adhesive,it is the new characteristics in the endemic fluorosis area.