The Systematic Analysis of the Impact of China Water Improvement and Fluoride Reduction Project on Children.

Endemic fluorosis is a serious public health problem in China. In order to improve the quality of drinking water, China has implemented water rehabilitation and fluoride reduction projects, but their effect on children's health outcomes is unclear. This study reviewed relevant literature published in PubMed, Web of Science, Embase, CNKI, VIP, and WanFang from the date of establishment to October 2024. Data related to demographic characteristics, duration of the water improvement project, geographical location, drinking water fluoride levels, and prevalence of dental fluorosis and urinary fluoride levels in children aged 8 to 12 years were extracted and analyzed using fixed-effects and random-effects models. With the improvement of water quality, the fluoride content decreased from 2.34 to 0.67 mg/L (drinking water standard, 1.5 mg/L). This was accompanied by a decrease in the prevalence of dental fluorosis from 56.7 to 28.8%. In regions where the drinking water fluoride content was within the limit, the prevalence of dental fluorosis decreased from 29.7 to 15.6%. The duration of implementation and geographical features of the regions under study had a significant impact on the prevalence of dental fluorosis. Finally, the urinary fluoride level decreased from 2.58 to 1.15 mg/L. The water improvement and fluoride reduction initiative effectively reduced the drinking water fluoride content and the urinary fluoride levels and the prevalence of dental fluorosis in children living in fluorosis-endemic areas in China. The improvement was associated with the geographical features of regions and the implementation time of the project.