Department of Pediatrics, Kangwon National University Hospital, Kangwon National University School of Medicine, Chuncheon, Republic of Korea.
Department of Preventive Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea.
Thyroid. 2020 Nov;30(11):1556-1565. doi: 10.1089/thy.2019.0436. Epub 2020 Jun 2.
Exposure to perfluoroalkyl substances (PFAS) has been suggested to affect thyroid function; however, data on early-life exposure and thyroid function in early childhood are scarce. We investigated the cross-sectional and longitudinal relationships of early-life exposure to PFAS with thyroid function at 2, 4, and 6 years of age. This study used data on PFAS exposure and thyroid function from the Environment and Development of Children (EDC) cohort study. A total of 660 children who visited at least once at 2, 4, or 6 years of age (381 children aged 2 years, 569 children aged 4 years, and 511 children aged 6 years) were included in this study. Serum thyrotropin (TSH) levels were measured at 2, 4, and 6 years of age. The relationship of serum PFAS (sPFAS) concentrations with TSH levels at the three time points was assessed by repeated-measure analysis using linear mixed models. The serum levels of free thyroxine (fT4) and triiodothyronine (T3) were measured once (at 6 years of age). The relationship of sPFAS with fT4 and T3 levels at 6 years of age was investigated by linear regression analyses. None complained of hyper- or hypothyroid symptoms with normal fT4 and T3 levels. Repeated-measure analysis showed that TSH levels at 2, 4, and 6 years of age were inversely associated with serum perfluorononanoic acid (sPFNA), after adjusting for age, sex, and/or dietary iodine intake ( < 0.05). When stratified by sex, TSH levels were inversely associated with serum perfluorooctanoic acid (sPFOA) in boys and sPFNA in girls ( < 0.05 for both). fT4 levels at 6 years of age were positively related to sPFNA and serum perfluorohexane sulfonic acid at 2 years of age and sPFOA at 6 years of age, and T3 levels at 6 years of age showed positive relationships with serum perfluorodecanoic acid and serum perfluorooctane sulfonic acid at 6 years of age ( < 0.05 for all). When stratified by sex, similar positive relationships for sPFAS with fT4 and T3 levels were significant among boys only. A significant relationship was found between early-life exposure to PFAS and thyroid function. Early-life exposure to PFAS was associated with decreased TSH and increased fT4 or T3 levels among preschool-age children.
全氟烷基物质（PFAS）暴露已被认为会影响甲状腺功能；然而，关于儿童早期暴露和甲状腺功能的早期数据仍然很少。我们研究了儿童早期暴露于 PFAS 与 2、4 和 6 岁时甲状腺功能的横断面和纵向关系。 这项研究使用了环境与儿童发展（EDC）队列研究中关于 PFAS 暴露和甲状腺功能的数据。共有 660 名至少在 2、4 或 6 岁时访问过一次的儿童（2 岁儿童 381 名，4 岁儿童 569 名，6 岁儿童 511 名）被纳入本研究。在 2、4 和 6 岁时测量血清促甲状腺激素（TSH）水平。使用线性混合模型的重复测量分析评估了血清 PFAS（sPFAS）浓度与三个时间点 TSH 水平之间的关系。一次测量了游离甲状腺素（fT4）和三碘甲状腺原氨酸（T3）的血清水平（6 岁时）。线性回归分析研究了 sPFAS 与 6 岁时 fT4 和 T3 水平的关系。 所有儿童均无甲状腺功能亢进或甲状腺功能减退症状，且游离甲状腺素（fT4）和三碘甲状腺原氨酸（T3）水平正常。重复测量分析表明，在调整年龄、性别和/或膳食碘摄入量后，2、4 和 6 岁时的 TSH 水平与血清全氟壬酸（sPFNA）呈负相关（<0.05）。按性别分层时，男孩的 TSH 水平与血清全氟辛酸（sPFOA）呈负相关，女孩的 TSH 水平与 sPFNA 呈负相关（均<0.05）。6 岁时 fT4 水平与 2 岁时 sPFNA 和血清全氟己烷磺酸以及 6 岁时 sPFOA 呈正相关，6 岁时 T3 水平与 6 岁时血清全氟癸酸和血清全氟辛烷磺酸呈正相关（均<0.05）。按性别分层时，仅在男孩中，sPFAS 与 fT4 和 T3 水平之间存在显著的正相关关系。 儿童早期暴露于 PFAS 与甲状腺功能之间存在显著关系。儿童早期暴露于 PFAS 与学龄前儿童 TSH 降低和 fT4 或 T3 水平升高有关。
