Ministry of Education-Shanghai Key Laboratory of Children's Environmental Health, Xinhua Hospital, Affiliated with Shanghai Jiao Tong University School of Medicine, Shanghai 200092, PR China; Children's Health Department, Shanghai Center for Women and Children's Health, Shanghai 200062, PR China.
Ministry of Education-Shanghai Key Laboratory of Children's Environmental Health, Xinhua Hospital, Affiliated with Shanghai Jiao Tong University School of Medicine, Shanghai 200092, PR China; Department of Gynaecology and Obstetrics, Xinhua Hospital, Affiliated with Shanghai Jiao Tong University School of Medicine, Shanghai, 200092, PR China.
Environ Int. 2020 Jan;134:105288. doi: 10.1016/j.envint.2019.105288. Epub 2019 Nov 22.
Despite the global abundance of studies on children's lead (Pb) exposure, the magnitude of Pb exposure among children across China remains unclear, especially for rural areas. In 2000, Pb was removed from petrol, marking a change in the sources of Pb exposure in China. To better understand children's Pb exposure and inform potential approaches to exposure reduction, we conducted a national blood Pb survey of 31,373 children (0-84 months old) from May 2013 to March 2015, using a multi-stage and multi-strata sampling method. Blood lead levels (BLLs) were tested using graphite furnace atomic absorption spectrometry with a detection limit of 1 µg/L. The results show that Chinese children had a contemporary geometric mean (GM) BLL of 26.7 μg/L, with 8.6% of BLLs exceeding 50 µg/L. Boys had higher BLLs (GM 27.2 μg/L) compared to girls (GM: 25.9 μg/L) (p < 0.001). Children at the age of 0-36 months had a lower PbB (GM 25.7 μg/L) level compared with those aged 36-84 months (GM 27.9 μg/L) (p < 0.001). When taking into account sociodemographic factors, a multivariate logistic regression analysis shows that the odds ratios (OR) of having a BLL of 27 µg/dL (i.e., median BLL of this study) or higher were 1.88 (95% CI: 1.76, 2.02) and 1.35 (95% CI: 1.22, 1.49) for homes using coal and biomass fuels, respectively, compared to those using gas or electricity. Meanwhile, children in homes close to roads were more likely to have BLLs exceeding 27 µg/dL (OR: 1.11, 95% CI: 1.03, 1.20). In China, rural children had higher BLLs compared to urban children. As a result of pediatric exposure to Pb, there were approximately 144 million and 36 million IQ points lost for rural children and urban children, respectively, revealing a disparity of Pb exposure between rural and urban areas in China. Cleaner domestic fuels and improved cooking/heating equipment will reduce contemporary Pb exposure in rural areas. In addition, the association between contemporary BLLs and distance away from roads further suggests that resuspension of legacy soil/dust Pb should not be neglected in future remediation programs and household interventions. As a large scale survey, this study provides evidence for revising the reference value of BLL, improving the guideline for clinical and public health management, and implementing interventions to prevent adverse health outcomes associated with low-level Pb exposure in children.
尽管全球有大量关于儿童铅暴露的研究，但中国儿童的铅暴露程度仍不清楚，尤其是农村地区。2000 年，中国停止在汽油中添加铅，这标志着铅暴露源发生了变化。为了更好地了解儿童的铅暴露情况，并为减少铅暴露提供潜在方法，我们于 2013 年 5 月至 2015 年 3 月期间采用多阶段、多层面抽样方法，对 31373 名（0-84 个月）儿童进行了全国性血铅调查。使用石墨炉原子吸收光谱法检测血铅水平（BLL），检测限为 1μg/L。结果显示，中国儿童当前的几何均数（GM）BLL 为 26.7μg/L，有 8.6%的 BLL 超过 50μg/L。与女孩（GM：25.9μg/L）相比，男孩（GM：27.2μg/L）的 BLL 更高（p<0.001）。0-36 个月儿童的血铅水平（GM：25.7μg/L）低于 36-84 个月儿童（GM：27.9μg/L）（p<0.001）。在考虑社会人口因素后，多变量逻辑回归分析显示，家中使用煤和生物质燃料的儿童 BLL 达到 27μg/dL（即本研究的中位数 BLL）或更高的比值比（OR）分别为 1.88（95%CI：1.76，2.02）和 1.35（95%CI：1.22，1.49），而家中使用燃气或电力的儿童 OR 为 1.00。同时，居住在道路附近的儿童血铅水平超过 27μg/dL 的可能性更高（OR：1.11，95%CI：1.03，1.20）。在中国，农村儿童的血铅水平高于城市儿童。由于儿童铅暴露，农村儿童和城市儿童的智商损失分别约为 1.44 亿和 0.36 亿点，表明中国农村和城市地区的铅暴露存在差异。使用更清洁的家用燃料和改进烹饪/取暖设备将减少农村地区的当代铅暴露。此外，当前 BLL 与距离道路的远近之间的关联进一步表明，在未来的修复计划和家庭干预中，不应忽视遗留土壤/灰尘铅的再悬浮。作为一项大规模调查，本研究为修订血铅水平参考值、改善临床和公共卫生管理指南以及实施干预措施以预防儿童低水平铅暴露相关不良健康后果提供了证据。
