Brown M J, Patel P, Nash E, Dikid T, Blanton C, Forsyth J E, Fontaine R, Sharma P, Keith J, Babu B, Vaisakh T P, Azarudeen M J, Riram B, Shrivastava A
Department of Social and Behavioral Sciences, Harvard Chan School of Public Health, Boston, Massachusetts, United States of America.
National Center for Disease Control India, New Delhi, India.
PLOS Glob Public Health. 2022 Oct 5;2(10):e0000743. doi: 10.1371/journal.pgph.0000743. eCollection 2022.
Childhood lead exposure remains a key health concern for officials worldwide, contributing some 600,000 new cases of intellectually disabled children annually. Most children affected by high exposure to lead live in low- and middle-income countries. The leaded gasoline phase out in India was completed in 2000. Yet, in 2020, an estimated 275 million children aged 0 to 9 years had blood lead levels (BLLs) ≥ 5 μg/dL known to adversely affect intelligence and behavior. Lead sources reported in India include spices, cookware, paint, traditional medicines and cosmetics, and lead-acid battery recycling and repair. However, their relative contribution has not been characterized. More than 200 lead pollution sites related to battery recycling and repair activities were identified in Bihar and Jharkhand, India. Ninety percent of the recycling sites had soil lead concentrations exceeding the US Environmental Protection Agency's standards. We compared blood and environmental lead levels in two groups of children in Patna, Bihar. Households in proximity to battery recycling operations (Proximal n = 67) versus households distal to these operations (Distal n = 68). The average age of children was 40 months; 46% were female. Overall, the geometric mean (GM) BLL was 11.6 μg/dL. GM BLLs of children in Proximal and Distal households were not significantly different (10.2 μg/dL vs. 13.1 μg/dL respectively; p≤0.07). About 87% children, 56 Proximal and 62 Distal had BLLs ≥5 μg/dl. Lead concentrations in environmental samples were significantly higher in Proximal households (soil mean 9.8 vs. 1.6 μg/ft2; dust mean 52.9 vs. 29.9 μg/ft2 p<0.001; Proximal vs. Distal respectively) whereas concentrations in all spices were higher in Distal households (mean 46.8 vs 134.5 ppm p<0.001; Proximal vs. Distal respectively), and turmeric (mean 59.4 vs. 216.9 ppm Proximal vs. Distal respectively). In multivariate analyses for all children lead in spices and turmeric and number of rooms in the house were significant while for the Proximal group only lead in spices remained in the model. The predictive value of these models was poor. For the Distal group, a model with lead concentration in spices, turmeric and soil and number of rooms in the house was a much better fit. Of the 34 water samples collected, 7 were above the Indian standard of 10 ppb for lead in drinking water (2 in the Proximal area, 5 in the Distal area). Children in Patna, Bihar, India are exposed to multiple sources of lead, with lead levels in house dust and loose, locally sourced spices the most likely to increase blood lead levels. A holistic approach to blood lead testing and source identification and remediation are necessary to prevent lead exposure.
儿童铅暴露仍是全球各国官员关注的关键健康问题,每年约导致60万新增智力残疾儿童病例。大多数铅暴露水平高的儿童生活在低收入和中等收入国家。印度在2000年完成了含铅汽油的淘汰。然而,在2020年,估计有2.75亿0至9岁儿童的血铅水平(BLLs)≥5μg/dL,已知这会对智力和行为产生不利影响。印度报告的铅源包括香料、炊具、油漆、传统药物和化妆品,以及铅酸电池回收和维修。然而,它们的相对贡献尚未得到明确界定。在印度比哈尔邦和贾坎德邦,发现了200多个与电池回收和维修活动相关的铅污染场地。90%的回收场地土壤铅浓度超过了美国环境保护局的标准。我们比较了比哈尔邦巴特那两组儿童的血液和环境铅水平。靠近电池回收作业的家庭(近端n = 67)与远离这些作业的家庭(远端n = 68)。儿童的平均年龄为40个月;46%为女性。总体而言,几何平均(GM)血铅水平为11.6μg/dL。近端和远端家庭儿童的GM血铅水平无显著差异(分别为10.2μg/dL和13.1μg/dL;p≤0.07)。约87%的儿童,近端56名和远端62名,血铅水平≥5μg/dl。近端家庭环境样本中的铅浓度显著更高(土壤平均9.8 vs. 1.6μg/ft²;灰尘平均52.9 vs. 29.9μg/ft² p<0.001;分别为近端与远端),而远端家庭所有香料中的铅浓度更高(平均46.8 vs 134.5 ppm p<0.001;分别为近端与远端),姜黄也是如此(平均59.4 vs. 216.9 ppm分别为近端与远端)。在对所有儿童的多变量分析中,香料和姜黄中的铅以及房屋房间数量具有显著性,而对于近端组,模型中仅保留了香料中的铅。这些模型的预测价值较差。对于远端组,一个包含香料、姜黄和土壤中的铅浓度以及房屋房间数量的模型拟合度要好得多。在采集的34份水样中,7份超过了印度饮用水铅标准10 ppb(近端地区2份,远端地区5份)。印度比哈尔邦巴特那的儿童接触多种铅源,家庭灰尘和当地采购的散装香料中的铅最有可能增加血铅水平。采取全面的血铅检测、源识别和修复方法对于预防铅暴露是必要的。