A benchmark dose analysis for children urinary fluoride and it's correlation with the prevalence of dental fluorosis / 公共卫生与预防医学

ABSTRACT

Objective To investigate the situation of drinking water fluorosis in Tianjin, to study the benchmark dose of urinary fluoride, and to provide a reference for the formulation of the standard for urinary fluoride. Methods Three fluorosis endemic areas were selected in Tianjin, and three villages in each area were selected in this study. The water fluoride was detected, and the prevalence of dental fluorosis and the urinary fluoride of children aged 8-12 years old were investigated. Results The prevalence of dental fluorosis and urinary fluoride content in children in the villages with water fluoride exceeding the standard were significantly higher than those in the villages with water fluoride qualified, and the difference was statistically significant (χ2=88.821, P＜0.001; Z=6.089, P＜0.001). The analysis of the prevalence of dental fluorosis in children showed that the younger the age, the lower the prevalence and severity of dental fluorosis (χ2trend=14.584, P2trend= 20.525, P2=0.736, P=0.391; χ2=3.649, P=0.456). There were significant differences in urinary fluoride between children with different ages and genders (H=14.768, P=0.011; Z=-2.526, P=0.012). According to the level of urinary fluoride, the children were divided into 5 groups. With the increase of urinary fluoride concentration, the prevalence of dental fluorosis gradually increased and the difference was statistically significant (χ2trend=16.348, P<0.001), showing a dose-effect relationship. Based on the prevalence of dental fluorosis in children, BMDS was used to calculate the BMD and BMDL, which were 2.20 mg/L and 1.54 mg/L, respectively. Conclusion The water reform and fluoride reduction in Tianjin has achieved certain results. There is a dose-effect relationship between urinary fluoride and prevalence of dental fluorosis in children, and the reference dose value is slightly higher than the current standard, suggesting that the current standard can be updated timely.