1 LaKind Associates, LLC, Catonsville, Maryland, USA.
2 Department of Epidemiology and Public Health, University of Maryland School of Medicine , Baltimore, Maryland, USA.
Environ Health Perspect. 2018 Sep;126(9):96002. doi: 10.1289/EHP1954.
The benefits of breastfeeding to the infant and mother have been well documented. It is also well known that breast milk contains environmental chemicals, and numerous epidemiological studies have explored relationships between background levels of chemicals in breast milk and health outcomes in infants and children.
In this paper, we examine epidemiological literature to address the following question: Are infant exposures to background levels of environmental chemicals in breast milk and formula associated with adverse health effects? We critically review this literature a) to explore whether exposure-outcome associations are observed across studies, and b) to assess the literature quality.
We reviewed literature identified from electronic literature searches. We explored whether exposure-outcome associations are observed across studies by assessing the quality (using a modified version of a previously published quality assessment tool), consistency, and strengths and weaknesses in the literature. The epidemiological literature included cohorts from several countries and examined infants/children either once or multiple times over weeks to years. Health outcomes included four broad categories: growth and maturation, morbidity, biomarkers, and neurodevelopment.
The available literature does not provide conclusive evidence of consistent or clinically relevant health consequences to infants exposed to environmental chemicals in breast milk at background levels.
It is clear that more research would better inform our understanding of the potential for health impacts from infant dietary exposures to environmental chemicals. A critical data gap is a lack of research on environmental chemicals in formula and infant/child health outcomes. https://doi.org/10.1289/EHP1954.
母乳喂养对婴儿和母亲的益处已有充分的记录。众所周知，母乳中含有环境化学物质，许多流行病学研究已经探索了母乳中化学物质的背景水平与婴儿和儿童健康结果之间的关系。
在本文中，我们检查了流行病学文献，以回答以下问题：婴儿暴露于母乳和配方奶中的环境化学物质背景水平是否与不良健康影响有关？我们批判性地审查了这一文献，a）探讨了是否在研究中观察到暴露-结果关联，b）评估文献质量。
我们审查了从电子文献搜索中确定的文献。我们通过评估质量（使用以前发表的质量评估工具的修改版本）、一致性以及文献的优缺点，来探讨是否在研究中观察到暴露-结果关联。流行病学文献包括来自多个国家的队列研究，并且在数周至数年的时间内对婴儿/儿童进行了一次或多次检查。健康结果包括四个广泛的类别：生长和成熟、发病率、生物标志物和神经发育。
现有文献没有提供确凿的证据表明，在背景水平下暴露于母乳中环境化学物质的婴儿会产生一致或临床上相关的健康后果。
很明显，更多的研究将更好地帮助我们了解婴儿从饮食中接触环境化学物质对健康的潜在影响。一个关键的数据差距是缺乏关于配方奶中环境化学物质和婴儿/儿童健康结果的研究。https://doi.org/10.1289/EHP1954.
