摘要目的 调查河南省许昌市饮水型氟中毒病区病情,评价改水工程运行时间对病情控制的效果.方法 采用多阶段随机数字抽样法,在河南省许昌市饮水型氟中毒病区按未改水,改水时间＜3、3～5、＞5年分层抽取15个氟中毒病区村.在每个病区村检查全部8～ 12岁儿童氟斑牙患病情况,抽取30名儿童采集尿样.采用Dean法检测儿童氟斑牙患病情况,离子选择电极法检测儿童尿氟含量.结果 未改水,改水时间＜3、3～5、＞5年组儿童氟斑牙检出率分别为53.57％ (120/224)、63.64％(98/154)、37.30％(47/126)、22.99％(40/174),尿氟几何均数分别为2.10、1.30、1.07、1.02 mg/L.改水时间3～5年、＞5年组儿童氟斑牙检出率与未改水组比较,差异有统计学意义(X2=8.56、38.10,P均＜0.008).3个改水组儿童尿氟含量分别与未改水组比较,差异有统计学意义(q=5.66、8.14、8.28,P均＜0.01).儿童尿氟水平与该村水氟含量、氟斑牙指数呈正相关(r=0.659、0.758,P均＜0.01).结论 饮水型氟中毒病区改水时间＜3年时,儿童尿氟含量就有明显下降.儿童氟斑牙发生与改水有关,改水时间越长,检出率降低越明显.

abstractsObjective To evaluate the effectiveness of prevention and control measures in drinking waterborn endemic fluorosis areas after water improvement in Xuchang City,Henan Province.Methods In the drinking water-born endemic fluorosis areas of Xuchang City,Henan Province,15 villages were selected based on the following parameters:the unimproved water group,the water improvement time ＜ 3 years group,the water improvement time 3-5 years group and the water improvement time ＞ 5 years group,using a multi-stage random sampling method.In those villages,the concentration of urinary fluoride was tested by the ion selective electrode method on 30 children selected by every village,and Deans method was applied for diagnosis of dental fluorosis on all students age 8-12 years old of the 15 villages.Results The dental fluorosis prevalence rates of the unimproved water group,the water improvement time ＜ 3 years group,the water improvement time 3-5 years group and the water improvement time ＞ 5 years group were 53.57％ (120/224),63.64％ (98/154),37.30％ (47/126) and 22.99％ (40/174),respectively,and the urinary fluoride geometry means were 2.10,1.30,1.07 and 1.02 mg/L,respectively.The prevalence of dental fluorosis was significantly different between the improvement time 3-5 years and the unimproved water groups (x2 =8.56,P ＜ 0.008),and between the improvement time ＞ 5 years and the unimproved water groups too (x2 =38.10,P ＜ 0.008).The geometric mean of urinary fluoride was significantly different between the improvement time ＜ 3 years and the unimproved water groups (q =5.66,P ＜ 0.01),between the improvement time 3-5 years and the unimproved water groups (q =8.14,P ＜ 0.01),and between the improvement time ＞ 5 years and the unimproved water groups (q =8.28,P ＜ 0.01).The level of urine fluoride in children was positively correlated with the fluoride content in the village (r =0.659,P ＜ 0.01),and was positively correlated with dental fluorosis index too (r =0.758,P ＜ 0.01).Conclusions The content of urinary fluoride has decreased significantly in less than three years after water improvement in drinking water-born endemic fluorosis areas.The incidence of dental fluorosis in children is related to the improvement of water supply.The longer the time of the water improvement,the more obvious the detection rate decreased more obvious.