Epidemiological investigation on endemic fluorosis of drinking water type in Ningjin, Xiajin and Wucheng counties in the northwest area of Shandong Province / 中华地方病学杂志

ABSTRACT

Objective To investigate the endemic fluorosis of drinking water type in 3 counties in the northwest of Shandong Province,and to provide scientific basis for prevention and control of endemic fluorosis.Methods Seven villages in 3 counties of Ningjin,Xiajin and Wucheng were investigated to achieve the results including fluoride of drinking water,8-12 year-old children's dental fluorosis incidence rate,the fluoride of urine,prevalence of skeletal fluorosis by clinical and X-ray diagnosis in adults over 30-year old,and the bone mineral density.At the same time,set up a control point to detect the adult bone density in non-ward village of each investigated county,The water and urine fluoride were checked by selective electrode method,dental fluorosis was diagnosed by Dean method (WS/T 208-2011) and the diagnosis of adult fluorosis was performed in accordance with the diagnostic criteria of endemic fluorosis (WS 192-2008),and bone mineral density was measured by EXA-3000.Results The villages in Ningjin and Wucheng had finished defluoridation,where the water fluoride was at normal level.In the 7 villages,the total detection rate of 8-12 year-old children's dental fluorosis was 85.09％ (411/483),dental fluorosis index was 1.88;the dental fluorosis detection rate in Wucheng,Xiajin and Ningjin was 92.48％ (295/319),88.76％ (79/89) and 49.33％ (35/75),respectively,the difference was statistically significant (x2 =90.26,P ＜ 0.01).The average urine fluoride geometric mean of children (206) and adults (298) was 3.29 and 3.41 mg/L,respectively.The urine fluoride of Xiajin was the highest in the 3 counties,and the average urine fluoride geometric mean of the two groups was as high as 5.11 and 6.30 mg/L,respectively.The total detection rate of clinical and radiographic skeletal fluorosis in adults was 30.07％ (92/306) and 14.38％ (44/306),respectively.The osteoporosis detection rate of adults in endemic fluorosis area and non-endemic fluorosis area was 33.11％ (100/302) and 8.99％ (17/189),respectively.The difference was statistically significant (x2 =37.25,P ＜ 0.01);the average bone mineral density in endemic area and non-endemic area was 0.416 and 0.475 g/cm2,respectively,the difference was statistically significant (t =8.508,P ＜ 0.01).Conclusions The endemic fluorosis in the 3 counties in the northwest of Shandong Province is still existed.The defluoridation has not been completed in Xiajin County.Therefore,it is necessary to implement defluoridation measures of the drinking water as soon as possible and strengthen the water fluoride monitoring so as to prevent and control endemic fluorosis.