Background

Humans are widely exposed to phthalates, which are metabolized in the body and excreted in urine. Phthalate metabolites are excreted within hours of exposure, making urinary phthalate biomarker concentrations highly variable.

Objective

The goal of this study was to characterize the long-term variability in phthalate biomarker concentrations in women across the midlife transition and to identify factors that may be associated with increased variability in those phthalate biomarker concentrations by analyzing longitudinal urinary phthalate metabolite data from the Midlife Women’s Health Study (2006–2015).

Methods

A total of 741 women were enrolled in the study for a period of up to 4 years, during which they each provided 2–4 urine samples per year over 4 consecutive weeks that were pooled for analysis (1876 total pools). Nine phthalate metabolites were assessed individually and as molar sums representative of common compounds (all phthalates: ƩPhthalates; DEHP: ƩDEHP), exposure sources (plastics: ƩPlastic; personal care products: ƩPCP), and modes of action (anti-androgenic: ƩAA). Phthalate metabolites were analyzed by quartile using generalized linear models. In addition, the impact of explanatory variables (race, annual family income, and type of work) on phthalate quartile was examined using ordinal logistic regression models.

Impact statement

Phthalate biomarker concentrations are highly variable among midlife women over time, and annual sampling may not be sufficient to fully characterize long-term exposure.

中文翻译：

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中年女性健康研究中邻苯二甲酸酯代谢物的逐年变化

背景

人类广泛接触邻苯二甲酸盐，邻苯二甲酸盐在体内代谢并通过尿液排出体外。邻苯二甲酸酯代谢物在暴露后数小时内被排出，使得尿液中邻苯二甲酸酯生物标志物浓度变化很大。

客观的

本研究的目的是描述女性在中年过渡期间邻苯二甲酸酯生物标志物浓度的长期变异性，并通过分析中年女性的纵向尿液邻苯二甲酸酯代谢物数据来确定可能与这些邻苯二甲酸酯生物标志物浓度变异性增加相关的因素。健康研究（2006-2015）。

方法

共有 741 名女性参与了这项为期 4 年的研究，在此期间，她们每人每年在连续 4 周内提供 2-4 个尿液样本，并汇总进行分析（总共 1876 个样本）。对九种邻苯二甲酸盐代谢物进行了单独评估，并以代表常见化合物的摩尔和（所有邻苯二甲酸盐：Ʃ邻苯二甲酸盐；DEHP：ƩDEHP）、暴露源（塑料：Ʃ塑料；个人护理产品：ƩPCP）和作用方式（抗雄激素：ƩAA） 。使用广义线性模型按四分位数分析邻苯二甲酸酯代谢物。此外，还使用序数逻辑回归模型检验了解释变量（种族、家庭年收入和工作类型）对邻苯二甲酸盐四分位数的影响。

影响报告

随着时间的推移，中年女性的邻苯二甲酸盐生物标志物浓度变化很大，每年采样可能不足以充分描述长期暴露的特征。