Analysis of drinking water-type endemic fluorosis monitoring results in Gansu Province in 2021 / 中华地方病学杂志

ABSTRACT

Objective:To investigate the epidemiological situation of drinking water-type endemic fluorosis in Gansu Province, and scientifically evaluate the effectiveness of water improvement and fluoride reduction projects in preventing and controlling the disease.Methods:The drinking water-type endemic fluorosis areas in Gansu Province were divided into five regions according to different ecological types: the Longzhong Loess Plateau Hilly Area in central Gansu, the Longdong Loess Plateau Gully Area in eastern Gansu, the Longnan Qinling Zhongshan Canyon Area in southern Gansu, the Gobi area of the Hexi Desert, and the Alpine Grassland Meadow Area in southern Gansu. In 2021, a survey was conducted on the basic situation, running situation of the water improvement and fluoride reduction projects, fluoride content in drinking water(fluorine ion-selective electrode), and the prevalence of dental fluorosis (Dean) among children aged 8 to 12 in all drinking water-type endemic fluorosis villages in the five regions. The pertinent assessments were executed in accordance with national guidelines such as the "Standards for Drinking Water Quality" (GB 5749-2006) and "Diagnosis of Dental Fluorosis" (WS/T 208-2011).Results:A total of 2 000 villages in drinking water-type endemic fluorosis areas were monitored, among which 1 999 villages had implemented water improvement and fluoride reduction projects, with a coverage rate of 99.95% (1 999/2 000). All water improvement and fluoride reduction projects were operating normally, with no intermittent operation or scrapping. A total of 34 616 children aged 8 to 12 were investigated for dental fluorosis. The detection rate of dental fluorosis was 4.18% (1 448/34 616), and the dental fluorosis index was 0.09. There was a statistically significant difference in the detection rate of dental fluorosis among children of different ages (χ 2 = 69.77, P < 0.001). The difference in the detection rate of dental fluorosis among children of different ecological types of areas was statistically significant (χ 2 = 775.11, P < 0.001). The dental fluorosis index of children aged 8 - 12 was significantly correlated with the historical water fluoride level ( r = 0.29, P = 0.042). The water improvement time in the Gobi area of the Hexi Desert was significantly correlated with the detection rate of dental fluorosis in local children ( r = - 0.48, P = 0.023). Conclusions:In 2021, the prevention and control of drinking water-type endemic fluorosis in all villages in Gansu Province has reached the national control standards. However, due to the different ecological characteristics and changes in water source distribution in different ecological types of areas, it is still necessary to further strengthen the monitoring of the condition of drinking water-type endemic fluorosis in all the affected villages and consolidate the existing prevention and control achievements.