Association between PFAS and thyroid hormones in US adults and the impact of smoking
Year: 2020
Type: conference-abstract
Abstract: Background/ Aim: Perfluoroalkyl acids (PFAS) are known endocrine disruptors with widespread persistence in the environment and near ubiquitous presence in blood. Their presence in blood has been associated with thyroid function disruption. Smoking has also been shown to affect thyroid function, with conflicting results from previous studies. Our objective was to assess the association between PFAS and thyroid function and to investigate effect modification of PFAS-thyroid hormone associations by smoking status.Methods: We used the laboratory subsample of the 2011-2012 National Health and Nutrition Examination Survey and selected adults (> 20 years) without reported thyroid disease or use of thyroid medication (n= 1,325). We extracted serum concentrations of the following PFAS: PFOA, PFOS, PFHxS and PFNA, as single compounds and summed them after converting compounds to molar weights (total PFAS). PFAS and thyroid hormones (TSH, free T4, total T4) were natural log transformed. Smoking status was defined using questionnaire data. Multivariable linear models were adjusted for sex, age, BMI and smoking; effect modification of smoking status was explored.Results: The total serum PFAS geometric mean was 55.2 (±1.7) µmol/L. After adjustment, there was a significant positive association between total PFAS and free T4 (βadj= 0.023 (95% CI: 0.009-0.038); p=0.0038, but not with TSH and total T4. After stratification by smoking status, there was a significant positive association between total PFAS and free T4 in non-smokers (βadj= 0.026 (95% CI: 0.010-0.043); p=0.0036), but not in smokers (p=0.7755). There was no statistically significant multiplicative interaction between smoking status and total PFAS (p=0.2201).Conclusion: PFAS may disrupt thyroid function and are associated with increasing free T4; this association was not found in smokers. There is a critical need to better understand the complex thyroid hormone axis, which can be targeted by PFAS at various levels, and the role of smoking on this.
Source: ISEE Conference Abstracts
Authors: M. van Gerwen, M. Alsen, N. Alpert, E. Taioli, E. Genden
Institution: Icahn School of Medicine at Mount Sinai
Language: English
Subfield: Environmental Chemistry
Field: Environmental Science
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W3170119196