Surveillance for endemic fluorosis related with brick tea drinking in Xinjiang, 2009-2012

Objective To understand the usage of brick tea, prevalence of dental fluorosis in children aged 8 to 12 years and skeletal fluorosis in adults aged 36 to 45 years in endemic fluorosis area in Xinjiang during 2009-2012. Methods Epidemiological survey was conducted. Dental fluorosis in local children were examined by using Dean's Index. X-ray detection of skeletal fluorosis was performed in local adults. Results The usage of brick tea was prevalent in these areas, 98% of local people drunk brick tea. The brick tea sample detection indicated that the fluorine content ranged from 544.82 mg/kg to 779.79 mg/kg, the person's average daily intake of fluorine was 6.08 mg and the qualified rate of brick tea was 28%. The overall detection rate of dental fluorosis was 6.08%, the dental fluorosis index was 0.13 and the intensity of dental fluorosis prevalence was mild. The overall detection rate of skeletal fluorosis in adults was 11.36%. Conclusion The person's average daily intake of fluorine was high in endemic fluorosis areas in Xinjiang. The prevalence of dental fluorosis in children and skeletal fluorosis in adults were mild in these areas. The qualified rate of brick tea was low. It is important to supply the brick tea with low fluorine content in theses areas.