RESUMEN
Objective To explore the potential correlation between fluoride levels of urine and influencing factors in water-high-fluoride areas.Methods In 2010,based on plain area,mountainous area and mixed area (altitudes were 898,2 200,1 460 m,respectively),3 villages of water-high-fluoride areas were selected by purpose sampling;pupils' family members were selected as survey population by cluster sampling.Questionnaire was conducted to collect general information;fluoride contents in urine and drinking water were measured using ionselective electrode.A linear multiple regression was used to examine which factors affected urinary fluoride.Results Totally there were 968 people distributed in plain area (444),mixed area (368) and mountainous area (156),medians of urinary fluoride level were 0.71,1.59 and 1.67 mg/L,respectively,the difference was significant (F =203.90,P ＜0.01);medians of water fluoride level in the three different habitats were 0.50,1.00 and 3.50 mg/L,respectively,the difference was significant (F =331.98,P ＜ 0.01).Age,gender,fluoride contents in drinking waters and habitat explained 33.1％ of urinary fluoride variation.Male had higher urine fluoride than female,older age and higher level fluoride in drinking water contributed to higher fluoride level in urine,higher altitude contributed to higher urinary fluoride.Conclusion Once fluoride content in urine is used to estimate fluoride exposure level among people in high fluoride area,gender and age must be taken in consideration.