An investigation of coal-burning type endemic fluorosis in Fuyuan County of Yunnan Province / 中华地方病学杂志

ABSTRACT

Objectives To study the prevailing status of coal-burning type endemic fluorosis in Fuyuan County of Yunnan Province, and to provide a scientific basis for fluorosis control and prevention. Methods In 2013, five towns were selected from the villages and towns which the defluoridation stove project was implemented and by the end of 2007 defluoridation stove rate was higher than 95%(including 95%), and two natural villages were selected in each township to carry out the investigation. Dental fluorosis was examined of all children aged 8 to 12 of survey points. At least 20 people were selected in each village. At the same time, 20 copies of instant urine samples were collected from these children of half male and half female, and urinary fluoride was determined. Then five natural villages were sampled from all survey points, and permanent residents were divided into25-,35-,45-,55-and≥65groups according to age. Six people were selected from each group with male and female in half who were conducted examination of adult skeletal fluorosis by X-ray. Dental fluorosis diagnosis was based on theDental Fluorosis Diagnosis(WS/T 208-2011). Urinary fluoride determination was done in accordance withUrine-Determination of Fluoride-Ion Specific Electrode Method(WS/T 30-1996). Skeletal fluorosis diagnosis was carried out according to Diagnostic Criteria for Endemic Skeletal Fluorosis (WS 192-2008). Results A total of 556 children aged 8 to 12 were monitored, the detection rate of dental fluorosis was 41.55%(231/556), the dental fluorosis index was 0.78. The very mild, mild, moderate and severe proportions of children's dental fluorosis were 20.50%(114/556), 17.09%(95/556), 3.60%(20/556) and 0.36%(2/556), respectively, given priority to very mild. The prevalence of dental fluorosis in children was increased with increasing age (χ2=74.27, P<0.05). One hundred and ninety-three copies of child urine samples were tested, the geometric mean of urinary fluoride was 0.62 mg/L, and the urinary fluoride contents were between 0.10-2.93 mg/L. A total of 116 adults were examined, and the detection rate of skeletal fluorosis was 9.48%(11/116). Detected cases of skeletal fluorosis was given priority to mild (9 cases, accounted for 81.81%), more men cases [16.36% (9/55)] than those of women [3.28% (2/61), χ2 = 5.77, P< 0.05]. Conclusion The hazard of coal-burning type fluorosis has been reduced in Fuyuan County , the affect of defluoridation stove project is obvious.