ObjectiveTo understand the harm of drinking-tea borne endemic flnorosis on human body and to provide a scientific basis for the formulation of effective control measures.MethodsSeven counties in Lhasa of Tibet were selected as monitoring counties in 2008.Four townships in each county were selected(including 2 villages in Chengguan county),and 2 administrative villages in each township were selected as monitoring villages.By using Dean method,dental fluorosis of every child aged 8 - 12 in the monitoring villages was examined.At the same time,urine samples were randomly collected in each age group in the above-mentioned villages.The content of fluoride in urine was determined by F-ion selective electrode (WS/T 30-1996) and evaluated according to “The Normal Concentration of Uriary Fluride of Population” (WS/T 256-2005).Over 18 years old in the monitoring counties were divided into five age group as - 25,- 35,- 45,- 55 and 56 -,at least 10 ment were randomly selected in each age group to be examined clinical skeletal fluorosis,and the diagnosis was based on the endemic skeletal fluorosis standard(WS 192-2007 ).At the same time,adult dental fluorosis diagnosis and urinary fluoride examination were done.Drinking water samples in each survey point were collected and water fluoride was determination by ion selective electrode method.Results①Dental fluorosis:a total of 723 children aged 8 to 12 were examined,91 cases of dental fluorosis were detected,and detection rate was 12.58％,dental fluorosis index was 0.34; ②adult dental fluorosis:a total of 2626 adults were examined,998 cases of dental fluorosis were detected,and detection rate was 38.00％,dental fluorosis index was 0.71; ③Adult clinical skeletal fluorosis:a total of 2626 adults were examined,15 degree Ⅱ clinical skeletal fluorosis patients were detected,and the detection rate was 0.57％ ; ④Child urine fluoride:a total of 700 child urine samples were collected.The geometric mean was 1.97 mg/L,ranged 0.01 to 17.56 rng/L; ⑤Adult urine fluoride:a total of 2626 adults were examined,geometric mean 2.16 mg/L,ranged 0.01 to 56.87 mg/L; ⑥Water fluoride:52 water samples were tested in survey sites,and fluoride content of 15 water samples exceeded the standard; ⑦Tea fluorine content:2000 tea samples were tested; median tea fluoride was 2.38 mg/L,ranged from 0.03 to 56.87 mg/L.ConclusionsFluorosis is serious in Lhasa,which is directly related to drinking brick tea,it is recommended that to drink brick tea with lowfluoride,and discard bad living habits.