Abstract: Objective To analyze the monitoring results of drinking water type endemic fluorosis in Minqin County and the investigation results of skeletal fluorosis. Methods From 2019 to 2022, a simple random sampling method was used to select Wanghua Village in Hongshaliang, Zhixiang Village in Xiqu, and Tiaoyuan Village in Donghu as fixed monitoring villages. Collect one deep well water sample from each monitoring village in five directions: east, west, south, north, and central, to determine water fluoride. According to the Hygienic Standard for Drinking Water (GB5749-2006), determine the excessive fluoride in water, and use the Diagnostic Standard for Endemic Skeletal fluorosis (WS192) to check and determine the occurrence of skeletal fluorosis. Analyze the monitoring results of water fluoride in drinking water endemic fluorosis areas in Minqin County from 2019 to 2022, the operation of water improvement projects in improved villages, the prevalence of skeletal fluorosis, and the age and gender distribution of skeletal fluorosis. Results From 2019 to 2022, the water fluoride levels in all three administrative villages were lower than 1.0mg/L, and there was no statistically significant difference in water fluoride levels between different years in the same administrative village (P>0.05). In the three administrative villages sampled and surveyed, all had completed water improvement in 2019, accounting for 100%, and the water improvement projects were all operating normally. A total of 1 663 people were investigated in three villages, of which the detection rate of clinical skeletal fluorosis was 2.47% (41/1663), among them, 14 were mild (34.15%), 19 were moderate (46.34%), and 8 were severe (19.51%). There was no statistical significance in the detection rate of different administrative villages (P>0.05). Among the 1 663 people surveyed, the number of male patients accounted for 1.21%, and the number of female patients accounted for 1.26%. There was no statistical significance between male and female in skeletal fluorosis (P>0.05). In different ages, the incidence rate of skeletal fluorosis was the highest among 50-60 people, which were 60-70 years old and 70-80 years old respectively, but there was no statistical significance between the groups (P>0.05). Conclusion The water improvement project has significantly improved the drinking water fluoride exceeding the standard in the drinking water endemic fluorosis area in Minqin County. The incidence of skeletal fluorosis is 2.47%, and there is no difference in the incidence rate among different gender and age groups.

Key words: Minqin County, drinking water type endemic fluorosis area, skeletal fluorosis, excessive fluoride in water