综合治理对燃煤污染型地方性氟中毒病区学龄儿童智力的影响

The effects of comprehensive control measures on intelligence of school-age children in coal-burning-borne endemic fluorosis areas

目的了解燃煤污染型地方性氟中毒（地氟病）病区学龄儿童氟斑牙、尿氟及智力水平情况，探讨综合治理对地氟病病区儿童智力发育的影响。方法2012年，在贵州省毕节市，选择鸭池镇下坝村和千溪乡中屯村（改炉改灶及健康教育综合治理时间超过3年）、海子街镇沙地村和八寨镇毛栗坪村（改良炉灶和健康教育综合治理时间〈1年），以村小学8—12岁学生为调查对象，分别作为治理时间长组、治理时间短组。同时选择毕节市七星关区第八小学学生作为对照组。氟斑牙检查采用Dean法，尿氟测定采用氟离子选择电极法，智商检查采用《瑞文标准推理测验》。结果对照组学龄儿童104人，氟斑牙检出率为0（0／104）；治理时间长组298人，氟斑牙检出率为72．5％（216／298）；治理时间短组339人，氟斑牙检出率为85-3％（289／339）；治理时间长组、治理时间短组氟斑牙检出率比较差异有统计学意义（χ2=15．736，P〈0．01）。治理时间长组、治理时间短组儿童尿氟含量[（2．33±0．18）、（3．03±0．16）mg／L]均高于对照组[（1．34±0．64）mg／L，F=306．53，P〈0．01]。对照组儿童中等以上智商占97．1％（101／104），明显高于治理时间长组[594％（177／298）]和治理时间短组[55．2％（187／339）]，病区经过长时间治理后，低年龄组（8-10岁）儿童智力低下的检出率明显降低（χ2=7．542，P〈0．01）。儿童尿氟含量与智力水平具有负相关性（r=-0．553，P〈0．01）。结论地氟病病区儿童智力发育较对照组儿童明显迟缓，经过一定时间的综合治理后，低年龄组儿童智力发育迟缓现象有明显改善。

Objective To investigate the incidence of dental fluorosis, urinary fluoride level and intelligence of children who lived in the coal-burning-borne endemic fluorosis areas and to reveal the effects of comprehensive control measures on intelligence of children in this area. Methods Children aged 8 - 12 who lived in coal-burning-borne endemic fluorosis areas in Bijie City of Guizhou Province were selected and divided into two groups according to the duration of comprehensive treatments given： long treatment group （Xiaba Village and Zhongtun Village, furnace stove was changed and comprehensive control measure of health education was carried out for more than 3 years） and short treatment group（Chadi Village and Maoliping Village, stoves were improved and health education time 〈 1 year）. The children who lived in a non-fluorosis area were selected as controls in 2012. Dental fluorosis was diagnosed by the method of Dean; urinary fluoride was analyzed by the method of fluoride-ion selective electrode; and the intelligence quotient（IQ） was measured by Raven＇s Standard Progressive Matrices Test. Results The number of children surveyed in control group was 10d, long treatment group was 298, short treatment group was 339, and the incidence rates of dental fluorosis were 0 （0/104）, 72.5%（216/298） and 85.2% （289/339）, respectively, and the incidence rates of dental fluorosis in children lived in the endemic fluorosis areas were significantly increased compared with that of control group; the difference of incidence rates between longtreatment group and short treatment group was statistically significantly（χ2 = 15.736, P〈 0.01 ）. Urinary fluoride content were （2.33 ± 0.18） and （3.03 ± 0.16）mg/L, respectively, compared with the control group[（1.34± 0.64） mg/L] ,the values in endemic fluorosis areas were significantly higher（F = 306.53, P 〈 0.01 ）. Above average IQ of children in the control group was 97.1% （101/104）, which was significantly higher than that of long and short treatment groups; after a lengthy treatment, mental retardation detection rate was significantly lower in the low-age group, 8- 10 year-old children（χ2 = 7.542, P 〈 0.01）. Urinary fluoride content was negatively correlated with the level of IQ （r = - 0.553, P 〈 0. 01 ）. Conclusions The intelligence development of children in coal-burning- borne endemic fluorosis area is significantly delayed. After a certain period of comprehensive treatment, the decreased level of cognition is inhibited and the mental retardation in the low-age group is improved.