Long-term reproductive effects of benzo(a)pyrene at environmentally relevant dose on juvenile female rats

Abstract

Since studies on the reproductive consequences after the exposure to environmentally relevant doses of Benzo(a)pyrene (BaP) during critical stages of development are scarce, this study evaluated female reproductive parameters of adult rats exposed to a low dose of BaP during the juvenile phase. Female rats (Post-natal 21) were treated with BaP (0 or 0.1 µg/kg/day; gavage) for 21 consecutive days. During the treatment, no clinical signs of toxicity were observed. Nevertheless, the ages of vaginal opening and first estrus were anticipated by the BaP-exposure. At the sexual maturity, the juvenile exposure compromised the sexual behavior, as well as the placental efficiency, follicle stimulating hormone levels, placenta histological analysis, and ovarian follicle count. A decrease in erythrocyte, platelet, and lymphocyte counts also was observed in the exposed-females. Moreover, the dose of BaP used in this study was not able to produce estrogenic activity in vivo. These data showed that juvenile BaP-exposure, at environmentally relevant dose, compromised the female reproductive system, possibly by an endocrine deregulation; however, this requires further investigation.

Keywords:

• Polycyclic aromatic hydrocarbon
• benzo(a)pyrene
• endocrine disruptor
• puberty
• female fertility
• juvenile period
• rats

Acknowledgements

The authors are grateful to José Eduardo Bozano, of the Department of Structural and Functional Biology, Institute of Biosciences, São Paulo State University – UNESP, by technical assistance.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Correction Statement

This article has been republished with minor changes. These changes do not impact the academic content of the article.

Additional information

Funding

This work was financially supported by São Paulo Research Foundation (FAPESP) [Grants #2019/03284–6 and #2017/22176–4] and Coordination for the Improvement of Higher Education Personnel (CAPES).