上海市推广使用无铅汽油对儿童血铅水平影响的追踪调查

目的　研究推广使用无铅汽油前后儿童血铅水平的动态变化规律。方法　 1997年 8～9月间 ,在上海市 5个区县 30所托幼机构 196 9名 1～ 6岁儿童进行了血铅水平抽样调查 ,然后于1998年 4～ 6月及 1999年 8～ 9月对相应人群进行血铅水平两次追踪调查。调查采用末梢血纸片法血铅测定方法。结果　上海市儿童血铅水平几何均数在推广无铅汽油前为 83μg/L ,推广无铅汽油后的 1998年为 80 μg/L ,1999年为 76 μg/L ,与前一年相比血铅水平的变化均有显著意义 (t值分别为2 .2 190、4 .4 5 76 ,P值分别小于 0 .0 5和 0 .0 1) ;超过目前国际公认的儿童铅中毒诊断标准 (10 0 μg/L)的比例也由使用无铅汽油前的 37.8%下降到 1999年的 2 4 .8% ,差异有非常显著性 (u =8.82 4 7,P <0 .0 1)。儿童血铅水平几何均数下降幅度徐汇区为 10 μg/L、静安区 11μg/L、杨浦区 6 μg/L、嘉定区4 μg/L、崇明县 2 μg/L。 结论　推广使用无铅汽油可降低儿童的血铅水平。

The trends of changes in children's blood lead levels since the introduction of lead free gasoline in Shanghai

OBJECTIVE: To describe trends of changes in blood lead levels in children aged 1 - 6 years during the time period before and after introducing lead free gasoline in Shanghai 1997 and 1999. METHODS: Blood lead levels of 1 969 children aged 1 - 6 years were determined by a sampling survey in five districts of Shanghai in August and September, 1997. Blood lead levels of the same population were re-determined by the same method from April to June in 1998 and from August to September in 1999. Filter paper blood lead test was carried out monthly using the filter paper blood lead proficiency testing program of Centers for Disease Control in the United States. The results from blood lead samples were under acceptable ranges during the study. RESULTS: The geometric means of blood lead levels were 83 microgram/L in 1997, 80 microgram/L in 1998 and 76 microgram/L in 1999, respectively. The prevalence rates of childhood lead poisoning (blood lead level was equal or more than 100 microgram/L) were 37.8% in 1997, 25.7% in 1998 and 24.8% in 1999. The amounts of decrease on average blood lead levels in the five districts between 1997 and 1999 were 10 microgram/L, 11 microgram/L, 6 microgram/L, 4 microgram/L and 2 microgram/L, respectively. CONCLUSION: Lead poisoning is a preventable disease. The average levels of lead in young children in Shanghai decreased significantly after the introduction of lead free gasoline to Shanghai. Lead emissions from vehicles running on leaded gasoline was one of the important contributors to increase the children's blood lead levels in Shanghai. Lead poisoning is not evenly distributed among children in Shanghai, resulting in the different levels of decline.