Aker Amira M, Watkins Deborah J, Johns Lauren E, Ferguson Kelly K, Soldin Offie P, Anzalota Del Toro Liza V, Alshawabkeh Akram N, Cordero José F, Meeker John D
Department of Environmental Health Sciences, University of Michigan School of Public Health, 1415 Washington Heights, Ann Arbor, MI 48109, USA.
Department of Medicine, Georgetown University, 3900 Reservoir Rd NW, Washington, DC 20007, USA.
Environ Res. 2016 Nov;151:30-37. doi: 10.1016/j.envres.2016.07.002. Epub 2016 Jul 21.
Phenols and parabens are ubiquitous environmental contaminants. Evidence from animal studies and limited human data suggest they may be endocrine disruptors. In the current study, we examined associations of phenols and parabens with reproductive and thyroid hormones in 106 pregnant women recruited for the prospective cohort, "Puerto Rico Testsite for Exploring Contamination Threats (PROTECT)".
Urinary exposure biomarkers (bisphenol A, triclosan, benzophenone-3, 2,4-dichlorophenol, 2,5-dichlorophenol, butyl, methyl and propyl paraben) and serum hormone levels (estradiol, progesterone, sex hormone-binding globulin (SHBG), free triiodothyronine (FT3), free thyroxine (FT4) and thyroid stimulating hormone) were measured at up to two time points during pregnancy (16-20 weeks and 24-28 weeks). We used linear mixed models to assess relationships between exposure biomarkers and hormone levels across pregnancy, controlling for urinary specific gravity, maternal age, BMI and education. In sensitivity analyses, we evaluated cross-sectional relationships between exposure and hormone levels stratified by study visit using linear regression.
An IQR increase in methyl paraben was associated with a 7.70% increase (95% CI 1.50, 13.90) in SHBG. Furthermore, an IQR increase in butyl paraben as associated with an 8.46% decrease (95% CI 16.92, 0.00) in estradiol, as well as a 9.34% decrease (95% CI -18.31,-0.38) in estradiol/progesterone. Conversely, an IQR increase in butyl paraben was associated with a 5.64% increase (95% CI 1.26, 10.02) in FT4. Progesterone was consistently negatively associated with phenols, but none reached statistical significance. After stratification, methyl and propyl paraben were suggestively negatively associated with estradiol at the first time point (16-20 weeks), and suggestively positively associated with estradiol at the second time point (24-28 weeks).
Within this ongoing birth cohort, certain phenols and parabens were associated with altered reproductive and thyroid hormone levels during pregnancy. These changes may contribute to adverse health effects in mothers or their offspring, but additional research is required.
酚类和对羟基苯甲酸酯是普遍存在的环境污染物。动物研究证据和有限的人体数据表明它们可能是内分泌干扰物。在本研究中，我们调查了106名招募到前瞻性队列研究“波多黎各污染威胁探索试验点（PROTECT）”中的孕妇体内酚类和对羟基苯甲酸酯与生殖激素和甲状腺激素之间的关联。
在孕期的两个时间点（16 - 20周和24 - 28周）测量尿中暴露生物标志物（双酚A、三氯生、二苯甲酮 - 3、2,4 - 二氯酚、2,5 - 二氯酚、丁基、甲基和丙基对羟基苯甲酸酯）和血清激素水平（雌二醇、孕酮、性激素结合球蛋白（SHBG）、游离三碘甲状腺原氨酸（FT3）、游离甲状腺素（FT4）和促甲状腺激素）。我们使用线性混合模型评估整个孕期暴露生物标志物与激素水平之间的关系，并控制尿比重、产妇年龄、体重指数和教育程度。在敏感性分析中，我们使用线性回归评估按研究访视分层的暴露与激素水平之间的横断面关系。
甲基对羟基苯甲酸酯四分位间距增加与SHBG增加7.70%（95%可信区间1.50，13.90）相关。此外，丁基对羟基苯甲酸酯四分位间距增加与雌二醇降低8.46%（95%可信区间 - 16.92，0.00）以及雌二醇/孕酮降低9.34%（95%可信区间 - 18.31， - 0.38）相关。相反，丁基对羟基苯甲酸酯四分位间距增加与FT4增加5.64%（95%可信区间1.26，10.02）相关。孕酮与酚类始终呈负相关，但均未达到统计学显著性。分层后，甲基和丙基对羟基苯甲酸酯在第一个时间点（16 - 20周）与雌二醇呈提示性负相关，在第二个时间点（24 - 28周）与雌二醇呈提示性正相关。
在这个正在进行的出生队列研究中，某些酚类和对羟基苯甲酸酯与孕期生殖激素和甲状腺激素水平的改变有关。这些变化可能对母亲或其后代的健康产生不良影响，但还需要更多研究。
