Abstract: ObjectiveTo explore the interacive effect of fluoride and arsenic pollution on bone metabolism in exposed population.MethodsTotally 198 people with both fluoride and arsenic exposure were selected from Liuchang town of Qinzhen city,Guizhou province.Urinary fluorine(UF),urinary arsenic(UAs),urinary hydroxyproline(UHYP), urinary cross-linked N-telopeptides of type I collagen(UNTX),and bone strength index(STI)of the people were detected.The people were divided into groups according the contents of UF and UAs.ResultsThe content of UNTX in low fluoride and arsenic combined exposure group(26.82 nmol/mmol Cr)was lower than those of low fluoride exposure group and low arsenic exposure group(8.97 and 20.91 nmol/mmol Cr).The content of UNTX for low fluoride concentration and high arsenic concentration,high fluoride concentration and low arsenic concentration exposure groups(45.19 nmol/mmol Cr and 54.79 nmol/mmol Cr)was higher than those of the low fluoride exposure group and low arsenic exposure group(20.51 and 20.91 nmol/mmol Cr,8.97 and 33.68 nmol/mmol Cr).The interactive effect of fluoride and arsenic on UNTX was significant(P<0.01).The interactive effect of fluoride and arsenic on UHYP and STI was not significant(P>0.05).ConclusionUnder the specific exposure level,the interaction of low fluoride concentration and low arsenic concentration on UNTX was antagonistic,with synergistic under low fluoride concentration and high arsenic concentration,high fluoride concentration and high arsenic concentration.No interactive effect of fluoride and arsenic on HYP was observed.