Erdenebayar Erdenechimeg, Santos Keilah Dos, Edwards Alexjandria, Dugersuren Nyam-Osor, Ochir Chimedsuren, Nriagu Jerome
Department of Environmental Health, School of Public Health, Mongolian National University of Medical Sciences, Ulaanbaatar, 14210, Mongolia.
University of Michigan, Ann Arbor, MI, USA.
BMC Public Health. 2019 Feb 7;19(1):163. doi: 10.1186/s12889-019-6486-x.
The ger ("tent city") areas in Mongolia are a product of rapid urbanization and transitional economic development combine with lack of institutional, administrative and financial capacity of governments to cope with the pace. These areas have become traps for inequities in social and environmental services and the associated effects on human health. Disparities in childhood lead exposure in such communities are largely unexplored.
We measured the concentrations of lead in blood of children, aged 4-7 years, in Erdenet (Orkhon Province) and Darkhan (Darkhan-Uul Province), the second and third largest cities in Mongolia. A survey instrument was used to gather information on influencing factors on lead exposure and the Strengths and Difficulties Questionnaire (SDQ) was used to assess a spectrum of behavioral problems among the children.
The mean blood lead level (BLL) of children in the two cities was found to be 3.8 ± 2.6 μg/dL (range: < 1.5-17.2 μg/dL) and 27.8% of the children had BLLs ≥5 μg/dL. Average BLL of children in Erdenet (a mining center) was significantly higher than that for children in Darkhan, and there was statistically significant difference between average BLL of children who live in ger district (4.2 ± 2.8 μg/dL) compared to those of children in housing units within the city (3.2 ± 2.4 μg/dL). In spite of the low values, BLLs was significantly associated with a number of effects on the spectrum of behavioral disorders, specifically with the scores for hyperactivity, conduct disorder and pro-social behavior.
This study shows that childhood lead poisoning is common especially in ger communities of the urban areas of Mongolia. It contributes evidence showing that BLL low as 3.8 μg/dL can selectively activate some effects from a spectrum of likely behavioral disorders in children.
蒙古的“帐篷城”地区是快速城市化和经济转型发展的产物，同时政府在机构、行政和财政能力方面难以跟上这一发展步伐。这些地区已成为社会和环境服务不公平现象的陷阱，以及对人类健康产生相关影响的源头。此类社区儿童铅暴露的差异在很大程度上尚未得到研究。
我们测量了蒙古第二大城市额尔登特（鄂尔浑省）和第三大城市达尔汗（达尔汗乌勒省）4至7岁儿童的血铅浓度。使用一份调查问卷收集有关铅暴露影响因素的信息，并使用长处和困难问卷（SDQ）评估儿童中的一系列行为问题。
发现这两个城市儿童的平均血铅水平（BLL）为3.8±2.6μg/dL（范围：<1.5至17.2μg/dL），27.8%的儿童BLL≥5μg/dL。额尔登特（一个采矿中心）儿童的平均BLL显著高于达尔汗儿童，并且居住在“帐篷城”地区的儿童平均BLL（4.2±2.8μg/dL）与城市内居住单元中的儿童平均BLL（3.2±2.4μg/dL）之间存在统计学显著差异。尽管数值较低，但BLL与一系列行为障碍的多种影响显著相关，特别是与多动、品行障碍和亲社会行为的得分相关。
本研究表明儿童铅中毒很常见，尤其是在蒙古城市地区的“帐篷城”社区。它提供了证据表明，低至3.8μg/dL的BLL可选择性地引发儿童一系列可能行为障碍中的某些影响。
