2005年甘肃省饮水型氟中毒病区水氟和改水降氟工程调查

目的 了解2005年甘肃省饮水型氟中毒病区水氟分布和改水降氟工程现状.方法 对甘肃省地方性氟中毒病区饮水和改水降氟工程进行水氟监测和工程运转情况调查登记.水氟测定用氟离子选择电极法.结果 筛查了11个市(州)的34个县(区)354个乡(镇)的1576个村的水源.检测水样7829份,检测出水氟超标水样1891份,占24.15%.水氟均值≤1.0 mg/L的村为1185个,占调查村的75.19%;1.0 mg/L的村为391个,占24.81%;水氟最低为0.04 mg/L,最高为6.78 ms/L,以庆阳市、平凉市及定西市总体水氟均值较高,大于或接近1.0 mg/L.调查了993处改水降氟工程,对876处工程的饮水含氟量进行了检测,共检测水样3528份,有408份水样含氟量1.0 mg/L.其中≤1.0 mg/L的工程768处,占87.67%;1.0 mg/L的工程108处,占12.33%;水氟最高为5.27mg/L.剔除能正常运转但水氟超标部分,实际水氟合格且正常使用的工程682处,占68.68%.改水降氟的主要形式为打井和引水.结论 甘肃省筛查村的水氟超标仍较严重,有近1/3的改水工程报废或处于非正常运转状态,须尽快落实防治措施和加强改水降氟工程的监测和管理力度.

Survey on water fluoride content and water-improving defluoridation projects in the endemic fluorosis areas of Gansu Province in 2005

Objective To investigate the distribution of water fluoride and the present status of water- improving delluoridation projects in the endemic fluorosis areas in Gansu Province. Methods According to "The National Technical Scheme for Endemic Disease Control in 2004" for the water improving projects, water fluoride content was determined from fluorosis villages in 34 counties of 11 cities in Gansu Province. The fluoride content in drinking water was assessed by F-ion selective electrode. Results Water fluoride content was determined in 1576 fluorosis villages of 34 counties. Water fluoride content of 7829 water samples was determined, and the fluoride content of 1891 samples was over standard. Water fluoride content was ≤ 1.00 mg/L(accounting for 75.19%) in 1185 villages and 1.00 mg/L(accounting for 24.81%) in 391 villages; the highest water fluoride content was 6.78 mg/L Nine hundred and ninety three water-improving and defluoridation projects were determined. Water fluoride content of 867 water-improving and defluoridation projects was determined; 768 projects had water fluoride content ≤1.00 mg/L(accounting for 87.67%) and water fluoride content of 108 projects was 1.00 mg/L(accounting for 12.33%),with the highest water fluoride content being 5.27 mg/L. Water-improving and delluoridation projects mostly relied on drilling a well to obtain under-grand water. Abandoned projects accounted for 30%. Conclusions In 34 counties of 11 cites(prefecture), nearly 30% of the villages had water fluoride content exceeding the standard. The situation of endemic fluorosis control is still serious in Gausu Province, countermeasures for endemic fluorosis must be carried out as soon as possible and surveillance of water-improving and defluoridation projects must be strengthened.