Association between bisphenol A exposure and thyroid dysfunction in adults: a systematic review and meta-analysis

Abstract

The occurrence of thyroid dysfunction is affected by environmental factors, and BPA is a ubiquitous environmental pollutant with the potential to cause thyroid dysfunction. However, the limited epidemiological evidence shows an inconsistent association between BPA exposure and thyroid dysfunction. Therefore, the literature on the impact of BPA on thyroid was sorted and analyzed to study the relationship between BPA and adult thyroid function. The studies published on or before 23rd May 2022 from PubMed, Web of Science, and Scopus were collected analyzing the association between BPA exposure and the levels of thyroid hormones. The methodological quality of each study was assessed, the sensitivity analysis and subgroup analysis based on study population and gender were also performed, and publication bias was evaluated. A total of 2969 literature studies were retrieved. Based on inclusion and exclusion criteria, eleven studies were included. Our results showed that BPA concentration was negatively correlated with FT4 and TSH in males. Pooled correlation coefficients between BPA and FT4/TSH were −0.027 (95%CI = −0.030∼−0.024) and −0.058 (95%CI = −0.111∼−0.004). BPA concentration was positively correlated with FT4 in females, and the pooled correlation coefficient was 0.006 (95%CI = 0.003–0.008). The effects of BPA on thyroid hormone levels were significantly different between males and females. BPA may significantly decrease the levels of FT4 and TSH in males but increase the levels of FT4 in females. Considering the high heterogeneity among studies and the limited investigations into subgroups, the relationship between BPA exposure and thyroid dysfunction needs to be further investigated.

Relationship between bisphenol A and autoimmune thyroid disease in women of childbearing age

“…Furthermore, this study observed a correlation between urinary BPA and FT4 levels (r=0.29, P < 0.05), which aligns with findings in previous research. A systematic review and meta-analysis ( 14 ) on BPA exposure and thyroid dysfunction in adults revealed a positive correlation between BPA concentration and FT4 in females, and the pooled correlation coefficient was 0.006 (95%CI = 0.003-0.008). Nonetheless, there are studies that deviate from the results of this study.…”

Advancing Endocrine Disruptors via In Vitro Evaluation: Recognizing the Significance of the Organization for Economic Co-Operation and Development and United States Environmental Protection Agency Guidelines, Embracing New Assessment Methods, and the Urgent Need for a Comprehensive Battery of Tests

“…The process of deiodination, facilitated by the enzyme deiodinase (DIO1), plays a fundamental role in regulating the concentration of thyroid hormones in peripheral tissues and plasma [ 99 , 100 ]. Although there are numerous contaminants known to disrupt the action of thyroid hormones [ 101 , 102 , 103 ], the mechanisms behind these disruptions are only partially understood, resulting in a gap in current methods for detecting such chemicals.…”