Bernard Susan M, McGeehin Michael A
Johns Hopkins Bloomberg School of Public Health, Department of Environmental Health Sciences, Baltimore, Maryland 21205-2198, USA.
Pediatrics. 2003 Dec;112(6 Pt 1):1308-13. doi: 10.1542/peds.112.6.1308.
As part of an investigation into the impact of a potential revision in federal childhood lead poisoning prevention policy that would result in screening children for blood lead levels (BLLs) >or=5 micro g/dL rather than the current 10 micro g/dL, we analyzed the most recent available, nationally representative data to identify prevalence of BLLs >or=5 micro g/dL and socioeconomic and demographic characteristics of 1- to 5-year-old children with BLLs >or=5 but <10 micro g/dL.
We performed statistical analyses on data from the Third National Health and Nutrition Examination Survey (NHANES III) (1988-1994) to describe trends in BLLs >or=5 micro g/dL overall and among subpopulations of children <6 years old and to compare risk factors for falling within 1 of 3 groups of children (those with BLLs >or=5 but <10 micro g/dL; >or=10 but <20 micro g/dL; and >or=20 micro g/dL) using the group reported as 0.7 to <5 micro g/dL as the referent.
Overall prevalence of BLLs >or=5 micro g/dL among 1- to 5-year-old children was 25.6%, although most (76%) of these children had BLLs <10 micro g/dL. Children with BLLs >or=5 micro g/dL included 46.8% of non-Hispanic black children, 27.9% of Mexican American children, and 18.7% of non-Hispanic white children; 42.5% of children in housing built before 1946, 38.9% of children in housing built between 1946 and 1973, and 14.1% of children in housing built after 1973 had BLLs >or=5 micro g/dL. Compared with non-Hispanic white children, non-Hispanic black children were 3 times more likely to have a BLL >or=5 but <10 micro g/dL, 7 times more likely to have a BLL of 10-20 micro g/dL, and 13.5 times more likely to have a BLL >or=20 micro g/dL. Similar increases in the association between risk factor and BLL were seen with respect to other known risk factors including age of housing, region of the country, and poverty.
The high prevalence of BLLs >or=5 micro g/dL overall and within US subpopulations will be an important variable in any change in screening and intervention criteria. However, most children with BLLs >or=5 micro g/dL are below the current intervention level of 10 micro g/dL. Exposure to lead from multiple sources is suggested by the prevalence of BLLs >or=5 micro g/dL but <10 micro g/dL among children with uncertain risk factors. The probable presence of one or more known risk factors for childhood lead poisoning increases as BLL increases.
作为一项关于联邦儿童铅中毒预防政策潜在修订影响的调查的一部分，该修订将导致对血铅水平（BLL）≥5μg/dL而非当前的10μg/dL的儿童进行筛查，我们分析了最新可得的全国代表性数据，以确定BLL≥5μg/dL的患病率以及BLL≥5但＜10μg/dL的1至5岁儿童的社会经济和人口特征。
我们对第三次全国健康和营养检查调查（NHANES III）（1988 - 1994年）的数据进行了统计分析，以描述BLL≥5μg/dL的总体趋势以及6岁以下儿童亚群体中的趋势，并将儿童分为3组（BLL≥5但＜10μg/dL；≥10但＜20μg/dL；≥≥≥20μg/dL），以报告为0.7至＜5μg/dL的组作为参照，比较落入这3组之一的风险因素。
1至5岁儿童中BLL≥5μg/dL的总体患病率为25.6%，尽管这些儿童中的大多数（76%）BLL＜10μg/dL。BLL≥5μg/dL的儿童包括46.8%的非西班牙裔黑人儿童、27.9%的墨西哥裔美国儿童和18.7%的非西班牙裔白人儿童；居住在1946年以前建造房屋中的儿童有42.5%、居住在1946年至1973年建造房屋中的儿童有38.9%、居住在1973年以后建造房屋中的儿童有14.1%的BLL≥≥≥5μg/dL。与非西班牙裔白人儿童相比，非西班牙裔黑人儿童BLL≥5但＜10μg/dL的可能性高3倍、BLL为10 - 20μg/dL的可能性高7倍、BLL≥≥≥20μg/dL的可能性高13.5倍。在其他已知风险因素方面，包括房屋年代、国家地区和贫困状况，风险因素与BLL之间的关联也有类似增加。
BLL≥5μg/dL在美国总体人群和亚群体中的高患病率将是筛查和干预标准任何变化中的一个重要变量。然而，大多数BLL≥5μg/dL的儿童低于当前10μg/dL的干预水平。风险因素不确定的儿童中BLL≥5但＜10μg/dL的患病率表明存在多种铅暴露源。随着BLL升高，儿童铅中毒一个或多个已知风险因素可能存在的可能性增加。
