Department of Epidemiology and Biostatistics, University of South Carolina, Columbia, United States of America.
Department of Chemistry, Montana Tech, Butte, United States of America.
Sci Total Environ. 2020 Mar 10;707:135528. doi: 10.1016/j.scitotenv.2019.135528. Epub 2019 Nov 14.
This pilot study was conducted to determine if we could identify intrauterine exposure to metals in meconium, as a measure of exposure for mother-child pairs living in proximity to a mining operation.
We used meconium as a means to measure metal exposure in utero. We set out to quantify the exposure to selected metals that are currently being mined and also are found in the Superfund site in Butte, Montana, and to compare it to that of Columbia, South Carolina, US, where mining is not occurring.
This cross-sectional study was conducted between May and November 2018. We received Institutional Review Board approval and we consented women following the birth of their newborns, and collected meconium within 24 h of birth, without any identifiers. Each laboratory used the same protocol for collection, transport, and storage; and the same laboratory protocol was used for the analysis of all samples. Samples were digested using standard acid/peroxide digestion methods and measured by inductively coupled plasma mass spectroscopy.
We collected meconium specimens from 17 infants in Columbia, South Carolina and 15 infants in Butte, Montana. The concentrations found in Columbia were in the low μg kg range (or less) and were similar to the low levels that have been identified in other studies of meconium. The magnitude of the differences in concentrations found in Butte compared to Columbia was 1792 times higher for Cu, 1650 times higher for Mn, and 1883 times higher for Zn.
Using meconium to measure exposure of newborns has implications for risk assessment in a mining-exposed population. This approach was inexpensive and thorough. The magnitude of the differences in the metal levels identified from the two study sites suggests there is an urgent need for further research to learn if there are health consequences to these highly exposed infants.
本初步研究旨在确定我们是否可以在胎粪中识别出金属的宫内暴露，作为生活在采矿作业附近的母婴对子的暴露测量。
我们使用胎粪作为衡量子宫内金属暴露的一种手段。我们旨在量化目前正在开采的选定金属的暴露量，这些金属也存在于蒙大拿州比尤特的超级基金场址中，并将其与美国南卡罗来纳州哥伦比亚进行比较，因为那里没有采矿活动。
这项横断面研究于 2018 年 5 月至 11 月进行。我们获得了机构审查委员会的批准，并在新生儿出生后征得妇女同意，并在出生后 24 小时内收集胎粪，不带有任何标识符。每个实验室都使用相同的收集、运输和储存协议；并且对所有样本都使用相同的实验室协议进行分析。样品使用标准酸/过氧化物消化方法进行消化，并通过电感耦合等离子体质谱法进行测量。
我们从南卡罗来纳州哥伦比亚的 17 名婴儿和蒙大拿州比尤特的 15 名婴儿中收集了胎粪样本。哥伦比亚发现的浓度处于μg/kg 级（或更低），与其他胎粪研究中确定的低水平相似。比尤特与哥伦比亚相比，铜的浓度差异高达 1792 倍，锰的浓度差异高达 1650 倍，锌的浓度差异高达 1883 倍。
使用胎粪来衡量新生儿的暴露情况对处于采矿暴露环境中的风险评估具有重要意义。这种方法既经济又全面。从两个研究地点确定的金属水平差异的幅度表明，迫切需要进一步研究，以了解这些高度暴露的婴儿是否存在健康后果。
