2005-2007年陕西省饮用水含氟量和地方性氟中毒病情调查

目的 调查2005-2007年陕西省饮用水含氟量和地方性氟中毒病情,评价改水工程降氟效果.方法 根据以往调查资料,在陕西省选择地方性氟中毒病情流行的10个市作为调查地区,以村为调查点,每村按东、西、南、北、中5个方位抽取水源水5份,同时采集每个改水工程水源水1份、出厂水1份和末梢水2份,采用氟离子选择电极法或氟试剂分光光度法测定水氟;在饮用水含氟量>1.00 mg/L的人群中进行地方性氟中毒流行病学调查,采用Dean法进行8～12岁儿童氟斑牙诊断,成人氟骨症按<地方性氟骨症临床分度诊断>(GB16396-1996)诊断.结果 共测定6390个村的水源水含氟量,其中水氟在1.00～<2.00 mg/L的有2619个村,暴露人口为1 654 998人;水氟在2.00～<4.00 mg/L的有845个村,暴露人口为355 623人;水氟≥4.00mg/L的有272个村,暴露人口为111 466人.全省水氟中位数为1.15 mg/L.渭南、咸阳和榆林3个市水氟中位数>1.00 mg/L,为高氟水集中分布的地区.共检测了3115个改水工程水氟,其中水氟在1.00～<2.00 mg/L的有1269个,暴露人口为1 415 877人;水氟在2.00～<4.00 mg/L的有120个,暴露人口为43 888人:水氟≥4.00 mg/L的有14个,暴露人口为5960人.44 081名8～12岁儿童进行氟斑牙临床检查,检出16 489例氟斑牙患者,检出率为37.4%(16 489/44 081);对310 993名成人进行氟骨症临床检查,检出15 877例Ⅱ度以上氟骨症患者,检出率为5.1%(15 877/310 993).结论 高氟水在陕西省广泛分布,地方性氟中毒流行较严重,降氟改水工程质量有待进一步提高.

Investigation of drinking water fluoride and fluorosis in Shaanxi Province from 2005 to 2007

Objectives To investigate fluoride in drinking waters and fluorosis status and evaluate the effectiveness of fluoride-reducing projects in Shaanxi Province from 2005 to 2007. Methods In the Shaanxi province-wide, the 10 endemic areas of fluorosis were chosen according to historical data as focusing areas for investigation. The village was considered as investigation spot, 5 water samples were collected from each village for investigating of fluoride content. Four water samples were collected from each fluoride-reducing project for evaluating its effectiveness. Fluoride concentrations in drinking water were measured by fluoride-selective electrode method or speetrophotometry. When fluoride content in drinking water was greater than 1.00 mg/L, the epidemical study wasd conducted to investigate fluorosis patients, focusing on investigating of dental fluorosis prevalence in 8 to 12-year-old children and skeletal fluorosis prevalence in adults. Dental fluorosis of children was diagnosed by using Dean's method, and adult skeletal fluorosis was diagnosed according to National Standard for Clinical Diagnosis of Endemic Skeletal Fiuorosis(GB 16396-1996). Results The fluoride content in drinking water from 6390 villages was measured. The fluoride content of drinking water of 2619 villages ranged from 1.0 to<2.0 mg/L, where 1 654 998 people exposed. Additionally, the fluoride content of water of 845 villages ranged from 2.0 to<4.0 mg/L, where 355 623 people exposed. Moreover, the fluoride contents of water of 272 villages exceeded 4.0 mg/L, where 111 466 people exposed. The median of fluoride content in drinking water was 1.15% in the whole province, and fluoride content in drinking water exceeded 1.00 mg/L in Weinan, Xianyang and Yulin where were concentrated distribution areas of high fluoride water. Among 3115 fluoride-reducing projects, the fluoride content of drinking water of 1269 projects ranged from 1.0 to<2.0 mg/L, where 1 415 877 people exposed. Additionally, the fluoride content of drinking water of 120 projects ranged from 2.0 to<4.0 mg/L, where 43 888 people exposed. Moreover, the fluoride content of drinking water of 14 projects exceeded 4.0 mg/L, where 5960 people exposed. The detectable rate of dental fluorosis of 8 to 12 year-old children and skeletal fluorosis of adults reached 37.4%(16 489/44 081) and 5.1%(15 877/310 993), respectively. Conclusions The widely distribution of high-fluoride in drinking water still contributes to the prevalence of fluorosis in Shaanxi Province. The quality of fluoride-reducing projects should be further improved.