1 Columbia Center for Children's Environmental Health; Columbia University, New York, New York.
2 Department of Environmental Health Sciences; Columbia University, New York, New York.
Thyroid. 2019 May;29(5):631-641. doi: 10.1089/thy.2018.0417.
Penta-brominated diphenyl ethers (PentaBDEs) are endocrine-disrupting chemicals that structurally resemble thyroid hormones and were widely used as flame retardants in household consumer products from 1975 to 2004. Polybrominated diphenyl ethers (PBDEs) cross the placenta, and evidence suggests that for many children, body burdens may peak during the toddler years. This study aimed to understand the impact of exposure timing by examining both pre- and postnatal exposure to BDE-47, the predominant penta-brominated diphenyl ether congener detected in humans, in relation to thyroid hormone parameters measured during early childhood. The Columbia Center for Children's Environmental Health Mothers and Newborns Study is a prospective birth cohort of African American and Dominican maternal-child pairs. Pregnant women were recruited from two prenatal clinics in Northern Manhattan and the South Bronx between 1998 and 2006. Participants included 158 children with (i) plasma PBDE concentrations measured at birth and in the toddler years (age 2-3 years), and (ii) serum thyroid parameters measured at three and/or five years of age. Outcomes included concentrations of serum thyrotropin, free thyroxine, and total thyroxine. Children with high exposure to BDE-47 during the prenatal period (-17% [confidence interval -29 to -2]) or toddler age (-19% [confidence interval -31 to -5]) had significantly lower geometric mean thyrotropin levels compared to children with low BDE-47 exposure throughout early life. Associations with thyroxine were also inverse; however, they did not reach statistical significance at the = 0.05 level. Sex-stratified models suggest associations with postnatal exposure may be stronger among boys compared to girls. The thyroid regulatory system may be sensitive to BDE-47 during pre- and postnatal periods.
五溴二苯醚（PentaBDEs）是一种结构类似于甲状腺激素的内分泌干扰化学物质，1975 年至 2004 年期间被广泛用作家用消费品的阻燃剂。多溴二苯醚（PBDEs）可穿过胎盘，有证据表明，对于许多儿童来说，体内负荷可能在幼儿时期达到峰值。本研究旨在通过检查 BDE-47（人类检测到的主要五溴二苯醚同系物）的产前和产后暴露，了解暴露时间的影响，与儿童早期测量的甲状腺激素参数相关。哥伦比亚儿童环境健康中心母婴研究是一个前瞻性的非裔美国人和多米尼加母婴对出生队列。1998 年至 2006 年间，在北曼哈顿和南布朗克斯的两家产前诊所招募了孕妇。参与者包括 158 名儿童，（i）在出生时和幼儿期（2-3 岁）测量了血浆 PBDE 浓度，以及（ii）在 3 岁和/或 5 岁时测量了血清甲状腺参数。结果包括血清促甲状腺激素、游离甲状腺素和总甲状腺素的浓度。与整个生命早期 BDE-47 低暴露的儿童相比，产前（-17%[置信区间-29 至-2]）或幼儿期（-19%[置信区间-31 至-5]）高暴露的儿童的促甲状腺激素几何平均水平显著降低。与甲状腺素也呈负相关；然而，在=0.05 水平上没有达到统计学意义。性别分层模型表明，与产后暴露的关联在男孩中可能比女孩更强。甲状腺调节系统在产前和产后期间可能对 BDE-47 敏感。
