To master the current situation of prevention and control of drinking water-borne endemic fluorosis in Shandong Province, and to provide basic data for control and evaluation of drinking water-borne endemic fluorosis.

From June to December 2019, in accordance with the requirements of the "National Drinking Water-Borne Fluorosis Monitoring Program (2019 Edition)" and "Shandong Province Drinking Water-Borne Fluorosis Monitoring Program (2019 Edition)", cross-sectional survey method was used to monitor the operation of the water supply projects, the fluorine content in drinking water, and the condition of children with dental fluorosis in all the disease affected villages of the drinking water-borne endemic fluorosis counties (cities, districts) in 16 cities of Shandong Province. Water fluorine was detected by "Standard Examination Methods for Drinking Water-Nonmetal Parameters" (GB/T 5750.5-2006), and in accordance with the "Standards for Drinking Water Quality" (GB 5749-2006), the water fluorine content was judged to be qualified or not. The examination and determination of dental fluorosis in children adopted "Diagnosis of Dental Fluorosis" (WS/T 208-2011), and the detection rate of dental fluorosis was calculated, the detection rates of dental fluorosis were compared between water improvement villages and villages without water improvement, qualified water fluorine and unqualified water fluorine villages.

There were 9 475 drinking water-borne endemic fluorosis villages in 105 counties (cities, districts) in Shandong Province, of which 9 370 were water improvement villages, and the water improvement rate was 98.89%. Among all the water improvement villages, there were 9 318 projects in normal operation, 45 intermittent projects and 7 scrapped projects. Among all the drinking water-borne endemic fluorosis villages, 8 254 villages were qualified in water fluorine, and the qualified rate of water fluorine was 87.11% (8 254/9 475); among water improvement villages, 8 210 villages were qualified in water fluorine, and the qualified rate of water fluorine was 87.62% (8 210/9 370); among the villages without water improvement, 44 villages were qualified in water fluorine, and the qualified rate of water fluorine was 41.90% (44/105). The qualified rate of water fluorine in water improvement village was significantly higher than that in villages without water improvement (χ² = 193.31, P < 0.05). The detection rates of dental fluorosis in children in water improvement villages and villages without water improvement were 8.92% (25 624/287 405) and 12.70% (271/2 134), respectively, and the detection rate of dental fluorosis in children in villages without water improvement was higher than that in water improvement villages (χ ² = 37.23, P < 0.05). The detection rates of dental fluorosis in children in qualified water fluorine and unqualified water fluorine villages were 7.98% (20 200/253 082) and 15.62% (5 695/36 457), respectively, and the detection rate of dental fluorosis in children in unqualified water fluorine villages was higher than that in qualified water fluorine villages (χ ² = 2 283.76, P < 0.05).

Water improvement and fluorine reduction measures have been implemented in most drinking water-borne endemic fluorosis villages in Shandong Province, the detection rate of dental fluorosis in children in water improvement villages is lower than that in villages without water improvement. However, attention should be paid to the situation of water fluorine exceeding the standard and later management and maintenance to prevent the rebound of the disease.

Fluorine; Drinking water; Fluorosis, dental; Epidemiological monitoring