Histopathological Changes of Zebrafish (Danio rerio) Ovaries Exposed to Sub-lethal Concentrations of Methyl Paraben

Paraben compounds are used widely as preservatives to inhibit microbial growth and extend used in pharmaceuticals, hygienic, cosmetics, care products. They pose the potential for reproductive toxicity for users. This paper provides an overview of the applications of histopathological biomarkers in reproductive toxicity in zebrafish caused by methylparaben. The present study investigated the changes in ovarian histopathology and Gonad Somatic Index (GSI) in zebrafish (Danio rerio) adult female after exposure to 0.001, 0.01, 1 and 10 mg/L methylparaben for 3 weeks in semi-static condition. Histological preparations were stained with Hematoxylin & Eosin. The results showed that Treatment at 0.001 to 10 mg/L of methylparaben had no significant effect on the survival, and condition factor. But in all treatments, GSI decreased and ovarian complications include wrinkled ooplasm, impaired yolk production, granulomatous inflammation and proteinaceous fluid were observed in the interstitial space of treated zebrafish ovaries. Also, atresia of vitellogenic oocytes was determined. These data show that an increase in atretic follicles has negative effects on zebrafish fertility and continuous exposure to subacute sublethal concentrations of methylparaben increase estrogenic and irreversible effects on the reproductive in female zebrafish.