Abstract

Background:

Studies have evaluated environmental exposure to toxic metals such as arsenic (As), cadmium (Cd), manganese (Mn), or lead (Pb) on birth size; however, information on potential effects of exposures to metal mixtures is limited.

Objectives:

We assessed the association between metal mixtures (As, Cd, Mn, Pb) in umbilical cord blood and neonate size in Bangladeshi children.

Methods:

In this birth cohort study, pregnant women who were $\ge 18\text{\hspace{0.17em}years}$ of age with an ultrasound-confirmed singleton pregnancy of $\le 16\mathrm{wk}$ gestation were recruited from two Bangladesh clinics between 2008 and 2011. Neonate size metrics were measured at the time of delivery. Metals in cord blood were measured using inductively coupled plasma mass spectrometry. We employed multivariable linear regression and Bayesian kernel machine regression (BKMR) to estimate associations of individual metals and metal mixtures with birth size parameters.

Results:

Data from 1,088 participants was assessed. We found a significant negative association between metal mixture and birth length and head circumference when all metal concentrations were above the 60th and 55th percentiles, respectively, compared with the median. An interquartile range (IQR) increase in log Cd concentration {log[Cd (in micrograms per deciliter)] $\text{IQR}=2.51$} was associated with a 0.13-standard deviation (SD) decrease in mean birth length (95% CI: $-0.25$, $-0.02$) and a 0.17-SD decrease in mean head circumference (95% CI: $-0.28$, $-0.05$), based on linear regression models adjusted for covariates and the other metals. An IQR increase in log Mn concentration {log[Mn (in micrograms per deciliter)] $\text{IQR}=0.69$} was associated with a 0.07-SD decrease in mean birth weight (95% CI: $-0.15$, 0.002).

Discussion:

Metal mixtures in cord blood were associated with reduced birth size in Bangladeshi children. Results from linear regression models adjusted and the BKMR mixtures analyses suggest adverse effects of Cd and Mn, as individual metal exposures, on birth size outcomes. https://doi.org/10.1289/EHP7502

中文翻译：

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孟加拉国儿童的脐带血金属混合物和出生大小

摘要

背景：

研究评估了环境暴露于有毒金属，如砷 (As)、镉 (Cd)、锰 (Mn) 或铅 (Pb) 对出生体重的影响；然而，关于接触金属混合物的潜在影响的信息是有限的。

目标：

我们评估了孟加拉国儿童脐带血中的金属混合物（As、Cd、Mn、Pb）与新生儿大小之间的关联。

方法：

在这项出生队列研究中，怀孕的孕妇 $\ge 18\text{\hspace{0.17em}年}$ 超声确认单胎妊娠的年龄 $\le 16\mathrm{周}$2008 年至 2011 年期间，从孟加拉国的两家诊所招募了妊娠婴儿。在分娩时测量了新生儿的大小指标。使用电感耦合等离子体质谱法测量脐带血中的金属。我们采用多变量线性回归和贝叶斯核机器回归 (BKMR) 来估计单个金属和金属混合物与出生尺寸参数的关联。

结果：

评估了 1,088 名参与者的数据。我们发现，与中位数相比，当所有金属浓度分别高于第 60 个和第 55 个百分位数时，金属混合物与出生身长和头围之间存在显着的负相关。log Cd 浓度的四分位距 (IQR) 增加 {log[Cd（微克每分升）]$\text{智商}=2.51$} 与平均出生身长降低 0.13 标准差 (SD) 相关（95% CI： $-0.25$, $-0.02$) 和平均头围减少 0.17-SD (95% CI: $-0.28$, $-0.05$)，基于针对协变量和其他金属调整的线性回归模型。log Mn 浓度的 IQR 增加 {log[Mn（微克每分升）]$\text{智商}=0.69$} 与平均出生体重降低 0.07-SD 相关（95% CI： $-0.15$, 0.002)。

讨论：

脐带血中的金属混合物与孟加拉国儿童的出生体型减小有关。调整线性回归模型的结果和 BKMR 混合物分析表明，镉和锰作为个体金属暴露对出生尺寸结果的不利影响。https://doi.org/10.1289/EHP7502