School of Nursing, University of Pennsylvania, Philadelphia 19104-6096, USA.
Paediatr Perinat Epidemiol. 2012 Jan;26(1):61-9. doi: 10.1111/j.1365-3016.2011.01234.x. Epub 2011 Sep 20.
Children are especially vulnerable to lead toxicity, and exposure to lead has been linked to poor school performance and delinquency in children and adolescents. Even low-level lead exposure [blood lead level (BLL) <10 µg/dL] can cause intellectual deficit. In China, BLLs in children decreased slightly after the phasing out of lead in gasoline, but few studies have examined the sociodemographic factors associated with BLL above 10 µg/dL. In this study, we sought to examine the hypothesis that sociodemographic factors predict BLLs. We measured BLLs of 1344 preschool children (3-5 years old) from the China Jintan Child Cohort Study. Children's sociodemographic and health statuses, as well as parental sociodemographic data, were collected using questionnaires. Regression models were used to explore the association between sociodemographic factors and log-transformed BLLs as well as the relationship between sociodemographic factors and the risk of BLL ≥10 µg/dL. We found the median BLL to be 6.2 µg/dL (range: 1.8-32.0 µg/dL); 8% of children had BLLs ≥10 µg/dL. Boys had a higher median BLL (6.4 µg/dL) than girls and were more likely to have BLL ≥10 µg/dL [odds ratio = 1.77, 95% confidence interval 1.14, 2.74]. BLLs increased as children aged, with a median BLL of 6.6 µg/dL among 5-year-old children. Children with siblings had a higher average BLL and greater prevalence of a BLL ≥10 µg/dL than those without siblings. Living in a crowded neighbourhood was also associated with increased BLLs. Mother's lower education, father's occupation (as professional worker) and parental smoking at home were associated with increased BLLs. This study shows that children in this area still have relatively high BLLs even after the phasing out of leaded gasoline. Both children's and parental factors and community condition are associated with increased BLLs. Future efforts are needed to identify other sources of exposure and develop targeted prevention strategies.
儿童尤其容易受到铅毒性的影响，接触铅已被证明与儿童和青少年学习成绩差和犯罪行为有关。即使是低水平的铅暴露（血铅水平（BLL）<10μg/dL）也会导致智力缺陷。在中国，随着含铅汽油的逐步淘汰，儿童的 BLL 略有下降，但很少有研究探讨与 BLL 高于 10μg/dL 相关的社会人口因素。在这项研究中，我们试图检验社会人口因素预测 BLL 的假设。我们测量了来自中国金坛儿童队列研究的 1344 名学龄前儿童（3-5 岁）的 BLL。使用问卷收集了儿童的社会人口和健康状况以及父母的社会人口数据。回归模型用于探索社会人口因素与 BLL 的对数变换之间的关联，以及社会人口因素与 BLL≥10μg/dL 的风险之间的关系。我们发现中位数 BLL 为 6.2μg/dL（范围：1.8-32.0μg/dL）；8%的儿童 BLL≥10μg/dL。男孩的中位数 BLL（6.4μg/dL）高于女孩，且更有可能 BLL≥10μg/dL[比值比=1.77，95%置信区间 1.14-2.74]。随着儿童年龄的增长，BLL 也随之增加，5 岁儿童的中位数 BLL 为 6.6μg/dL。有兄弟姐妹的儿童的平均 BLL 更高，BLL≥10μg/dL 的患病率也更高。居住在拥挤的社区也与 BLL 增加有关。母亲较低的教育程度、父亲的职业（专业工人）和父母在家中吸烟与 BLL 增加有关。这项研究表明，即使在逐步淘汰含铅汽油后，该地区的儿童仍然存在相对较高的 BLL。儿童和父母的因素以及社区状况都与 BLL 增加有关。未来需要努力确定其他接触源，并制定有针对性的预防策略。
