Objective To understand the present status of water defluorination project and the efficiency of controlling endemic fluorosis in a county.
Methods During April through June, 2009, 8 towns were selected from the county by simple random sampling, 32 water defluorination projects were investigated for their quality and water fluoride contents were monitored. A total of 1 059 children between 8 and 12 years old were examined for dental fluorosis, and 50 children in the same age group were randomly selected from each town to be examined for their urine fluoride content.
Results Only 16 water defluorination projects were in normal use, the normal usage rate was 50.00%, 5 projects were in intermittent use. All the projects benefitted 18 835 residents altogether. The fluoride contents showed statistically significant differences between source water and tap water(T=1.000, P=0.001). The medians of the urine fluoride content of children in the selected 5 towns were greater than 1.40 mg/L. The average dental fluorosis rate in the examined children was 48.91%, the defect rate was 14.92%, and the dental fluorosis index was 1.06.
Conclusion The situation of the water defluorination projects was unacceptable, most of towns were threatened by the water with high fluoride content even started the defluorination project. The program of water defluorination has much work to do and long way to go.
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