ABSTRACT
Objective To investigate the dynamics and development trends of drinking water type of endemic fluorosis after water improvement in Xinbaerhuyouqi of Hulunbeir city, Inner Mongolia and to provide a scientific evidence for the development of countermeasures. Methods We mainly selected Adunchulusumu and Kerlunsumu in Xinbaerhuyouqi of Hulunbeir city as the two monitoring points after water improvement in 2000 -2009. Of these, 1 sample of centralized water supply source water and 3 samples of tap water and 5 samples of noncentralized water supply source water according to water well locations of east, west, south, north and center were collected and the levels of water fluoride were tested; the prevalence of dental fluorosis of school children aged 8 to 12 were examined; from 2002 onwards, the urine samples of 30 children aged 8 to 12(five age groups, six urine samples for each age group) were collected, and all urine samples were collected in the case of less than 30, and urine fluoride was tested. Dental fluorosis was diagnosed using Dean method; water fluoride was tested using fluoride ion selective electrode(WS/T 106-1999); urinary fluoride was tested by determination of fluoride in urine using ion-selective electrode(WS/T 89-1996). Results In 2000 - 2009, the mean levels of fluorine in drinking water in Adunchulusumu and Kerlunsumu were 1.79 - 4.35 mg/L and 1.38 - 3.18 mg/L, respectively; the detection rate of dental fluorosis of children aged 8 to 12 were 45.24％(19/42) - 89.78％(123/137) and 40.00％ (28/70) - 74.47％ (70/94), respectively; the median urinary fluoride of them were 2.30 - 4.15 mg/L and 2.73 - 4.55 mg/L, respectively. ConclusionsThe detection rate of children's dental fluorosis remains high in Xinbaerhuyouqi during the past 10 years after changing water. The endemic fluorosis remains a serious disease. Effective prevention and control measures must be taken to control the occurrence of fluorosis in the future.