Epidemiological survey on endemic fluorosis in Dongying city,Shandong province

Objective To investigate the epidemic status of endemic fluorosis in Dongying city. Methods The fluoride concentration of drinking water was tested in samples collected from 6 villages in 2008.Urinary fluoride levels and proportion of dental fluorosis were also evaluated for children aged 8-12 years old.The prevalence of skeletal fluorosis was diagnosed by X-ray in individuals over 16 years old.Results The average fluoride concentration of drinking water was 3.04 mg/L,which was higher than the national standard(≤1.0 mg/L).The maximum concentration of fluoride was as high as 4.15 mg/L.The prevalence rate of dental fluorosis was 59.7% in children aged 8-12 years old with average index of which as 1.2 and rate of dental damage as 11.8%.The worst situation was found in Matou Village,which had average index of dental fluorosis,prevalence rate of dental fluorosis and of dental damage as 1.51,69.4% and 21.5% respectively.The geometric mean concentration of urinary fluoride was 2.40 mg/L in children aged 8-12 years old.The prevalence rate of skeletal fluorosis was 14.8% in adults diagnosed by either X-ray or clinical symptom.Two cases of phase II skeletal fluorosis were found in Matou village.Conclusion The epidemic of endemic fluorosis was still serious in Dongying city.The measures of improvement of water quality and water defluoridation should be carried out as promptly as possible to prevent the endemic fluorosis in the city.