中国部分城市儿童血铅状况及其影响因素

Blood lead status and influencing factors among preschool children in urban areas of China

目的了解我国学前儿童血铅状况及其影响因素。方法2004年起连续5年采用分层整群随机抽样法抽取银川、西安、成都、武汉、合肥、北京、长沙、哈尔滨、郑州、呼和浩特、石家庄、海口、大连、青岛、广州、南宁各城市相同城区固定幼儿园及社区的69968名0～6岁儿童进行问卷调查，原子吸收法测定其血铅含量。结果（1）5年儿童血铅含量≥100μg/L平均检出率为7．57％，血铅平均水平为（45．00±2．05）μg/L，均低于我国既往调查。2004—2008年儿童血铅含量≥100汕g／L检出率分别为10．03％、7．85％、7．40％、6．91％、4．78％（X^2=297．36，P〈0．0001）。2004—2008年儿童血铅平均含量≥100μg/L检出率海口12．15％、郑州10．49％、广州10．37％、石家庄9．69％、长沙9．53％、西安9．46％、武汉9．40％、合肥8．50％、成都7．99％、银川7．98％、哈尔滨7．51％、北京6．10％、大连3．25％、呼和浩特2．89％、南宁2．46％、青岛2．39％（X^2=768．21，P〈0．0001）。（2）Logistic回归分析：母亲文化程度低、儿童年龄大、常咬文具／玩具、男性、在交通繁忙地带散步／玩耍时间较长、进食前不洗手、常食爆米花、常服中草药、常吸吮手指啃指甲、住房楼层低、室内墙皮脱落、常玩橡皮泥、住所周围有油漆／蓄电池／炼钢铁／炼油／印刷厂、离主干道较近是其血铅含量≥100μg/L的危险因素。散居、常服钙、铁、锌制剂、常食乳类及乳制品、母亲年龄较大是保护因素（P〈0．05）。结论儿童血铅含量≥100μg/L检出率高于发达国家，铅暴露是我国儿童的公共卫生问题。儿童血铅状况受外环境和自身多因素影响。政府及社会应以环境干预切断污染源为手段，以营养干预健康教育为方法．减少儿童铅暴露及其危害。

Objective To investigate the blood lead status and influencing factors among preschool children in the sampling city. Method Stratified-clustered-random sampling was used. Standardized questionnaire and peripheral blood samples were obtained from 69 968 children aged 0-6 years in fixed kindergartens and communities of Yinchuan, Xi＇ an, Chengdu, Wuhan, Hefei, Beijing, Harbin, Zhengzhou, Huhbot, Shijiazhuang, Haikon, Dalian, Qingdao, Cuangzhou, Nanning and Changsha from 2004 to 2008, respectively. Tungsten atomic absorhtion spectrophotometry was employed to determine the blood lead level of children. Result The proportion of children with blood lead level ≥100 μg/L was 7.57% （among which the proportion of high blood lead level, mild lead poisoning, moderate lead poisoning, severe lead poisoning were 91.0%, 2. 76% , 3.32%0 , 2. 93% , respectively） and the blood lead level was lower than those of the past studies. The proportion of high blood lead level has steadily declined from 2004 to 2008 [ the proportions were 10. 03% , 7.85%, 7.40% , 6. 91% and 4. 78% , respectively （X2 =297.36,P 〈 0. 0001 ）]. The proportion of children with blood lead level ≥100 μg/L in Haikou, Zhengzhou, Guangzhou, Shijiazhuang, Changsha , Xi＇an, Wnhan, Hefei, Chengdu, Yinchuan, Harbin, Beijing, Dalian, Huhhot, Nanning and Qingdao were 12. 15%, 10. 49%, 10. 37%e, 9. 69%, 9.53%, 9.46%, 9.40%, 8.50%, 7.99%, 7.98%, 7.51%, 6. 10%, 3.25%, 2. 89%, 2.46% and 2. 39%, respectively（ X2 =768.21, P 〈 0. 0001 ）. By multiple regression method, the risk factors which influenced blood lead status of children were education status of mother, older children, behavior and dietary habit of children, boy, stay for long time in traffic busy areas, the type of housing, taking traditional Chinese and herbal medicine. The protective factors against lead poisoning in children mainly included scattered living, the nutritional status of calcium, iron, zinc, frequent intake of milk, and older mother. Conclusion Theblood lead level of children has decreased, but is still higher than those in developed countries. Lead exposure remains a public health issue which affects children most. The blood lead leve! of children is affected by multiple factors. Government and the whole society should pay attention to interrupt the lead pollutant and to promote nutritional health education. With all these efforts, it is possible to stop the progress of lead exposure and reduce its hazardous effects on the ~rowth and development of children.