School of Public Health, National Defense Medical Center, Taipei, Taiwan.
National Institute of Environmental Health Sciences, National Health Research Institutes, Miaoli County, Taiwan.
Environ Health. 2022 Jul 1;21(1):61. doi: 10.1186/s12940-022-00873-9.
Phthalates are a group of industrial chemicals widely used in everyday products including cosmetics, food packaging and containers, plastics, and building materials. Previous studies have indicated that urinary phthalate metabolites are associated with metabolic effects including those on lipid metabolism, but the results are mixed. Furthermore, whether thyroid function mediates the association between phthalate exposure and lipid metabolism remains unclear. In the present study, we explored whether changes in thyroid function markers mediate the associations between phthalate exposure and lipid metabolism indicators in Taiwanese adults. The cross-sectional data were obtained from the Taiwan Environmental Survey for Toxicants conducted in 2013. Levels of 11 urinary phthalate metabolites, levels of 5 thyroid hormones, and 8 indicators of lipid metabolism were assessed in 222 Taiwanese adults. The relationships of urinary phthalate metabolite levels with serum thyroid hormone levels and lipid metabolism indicators were explored using multiple regression models. Mediation analysis was conducted to evaluate the role of thyroid function in the association between phthalate exposure and lipid metabolism. The metabolite of di(- 2-ethylhexyl) phthalate (∑DEHPm) exhibited a significant positive association with the lipid metabolite indicator of high-density lipoprotein cholesterol (HDL-C; β = 0.059, 95% confidence interval [CI] = 0.009, 0.109) in adults, and the thyroid function indicator thyroxine (T) had a significant negative association with the metabolite ∑DEHPm (β = - 0.059, 95% CI = - 0.101, - 0.016) and a significant negative association with HDL-C (β = - 0.284, 95% CI = - 0.440, - 0.128). The T indirect effect was 0.015 (95% CI = - 0.0087, 0.05), and the mediation effect was 32.2%. Our results support the assumption that exposure to phthalates influences the homeostasis of lipid metabolism by interfering with thyroid function.
邻苯二甲酸酯是一组广泛应用于日常产品的工业化学物质，包括化妆品、食品包装和容器、塑料和建筑材料。先前的研究表明，尿邻苯二甲酸酯代谢物与代谢效应有关，包括脂质代谢，但结果不一。此外，甲状腺功能是否介导邻苯二甲酸酯暴露与脂质代谢之间的关联尚不清楚。在本研究中，我们探讨了台湾成年人中甲状腺功能标志物的变化是否介导了邻苯二甲酸酯暴露与脂质代谢指标之间的关联。横断面数据来自于 2013 年进行的台湾环境毒物调查。在 222 名台湾成年人中评估了 11 种尿邻苯二甲酸酯代谢物、5 种甲状腺激素和 8 种脂质代谢指标的水平。使用多元回归模型探讨了尿邻苯二甲酸酯代谢物水平与血清甲状腺激素水平和脂质代谢指标之间的关系。通过中介分析评估了甲状腺功能在邻苯二甲酸酯暴露与脂质代谢之间的关联中的作用。二-(2-乙基己基)邻苯二甲酸酯(∑DEHPm)的代谢物与高密度脂蛋白胆固醇(HDL-C；β=0.059，95%置信区间[CI]为 0.009，0.109)呈显著正相关，甲状腺功能指标甲状腺素(T)与代谢物∑DEHPm呈显著负相关(β=-0.059，95%CI=-0.101，-0.016)，与 HDL-C 呈显著负相关(β=-0.284，95%CI=-0.440，-0.128)。T 的间接效应为 0.015(95%CI=-0.0087，0.05)，中介效应为 32.2%。我们的结果支持这样的假设，即邻苯二甲酸酯的暴露通过干扰甲状腺功能影响脂质代谢的内稳态。
