Bisphenol‑S Influence on Oxidative Stress and Endocrine Biomarkers of Reproductive System: A Systematic Review and Meta‑Analysis

Bisphenol‑S (BPS), as a new human public health concern, was introduced to the plastic industry by BPA‑free labeled products following the restrictions of Bisphenol‑A (BPA) as a safe alternative. However, recent research has revealed a controversial issue. In this regard, the present study aimed to review the relationship between BPS exposure and reproductive system dis/ malfunction.

PubMed and other databases were searched up to January 2021. The standard mean difference (SMD) with a 95% confidence interval (CI) was calculated for the main parameters using the random‑effects model. Finally, 12 studies with 420 subjects were included in this research. Forest plot, meta‑regression, and non‑linear dose‑response effect were calculated for each parameter by random‑effects model.

Based on the results of in vitro assessment, a significant increase was found in the oxidative stress parameters, including superoxide dismutase (SMD: 0.63, 95% CI: 0.321, 0.939), thiobarbituric acid reactive substances (SMD: 0.760, 95% CI: 0.423, 1.096), and reactive oxygen species (SMD: 0.484, 95% CI: 0.132, 0.835). In addition, the hormonal assessment revealed a significant decrease in male testosterone concertation (SMD: ‑0.476, 95% CI: ‑0.881, ‑0.071). Moreover, in vivo examination revealed a significant decrease in hormonal parameters, such as female testosterone (SMD: ‑0.808, 95% CI: ‑1.149, ‑0.467), female estrogen (SMD: ‑2.608, 95% CI: ‑4.588, ‑0.628), female luteinizing hormone (SMD: ‑0.386, 95% CI: ‑0.682, ‑0.089), and female follicle‑stimulating hormone (FSH) (SMD: ‑0.418, 95% CI: ‑0.716, ‑0.119). Besides, linear and non‑linear correlations were detected in the main parameters.

In conclusion, based on the current meta‑analysis, BPS was suggested to be toxic for the reproductive system, similar to the other bisphenols. Moreover, a possible correlation was indicated between oxidative and hormonal status disruption induced by BPS in male and female reproductive systems dis/malfunction.