Testicular Histomorphometry and Spermatogenic Indices Following Chronic Exposure to Petroleum Hydrocarbons in Male Wistar Rats: Relevance to the Niger Delta

Environmental exposure to petroleum hydrocarbons in the Niger Delta region of Nigeria is well established, yet the histomorphometric consequences of such exposure on testicular structure and spermatogenesis have received limited systematic attention. Hydrocarbons can act as endocrine disruptors, interfering with androgen signalling, Sertoli cell function, and spermatogenic progression. This study aims to evaluate the effects of chronic exposure to crude oil and its refinery derivatives on testicular histomorphometry and spermatogenic indices in male Wistar rats. Rats will be divided into control, crude oil, kerosene, and diesel exposure groups using dermal and inhalation exposure routes at environmentally relevant doses for 12 weeks. Testicular weight, germinal epithelium height, Sertoli cell counts, spermatogonial density, and primary spermatocyte index will be evaluated using stereological analysis of haematoxylin and eosin stained sections. Serum testosterone levels will be measured by enzyme-linked immunosorbent assay to complement the histological data. Findings will be correlated with environmental monitoring data from Niger Delta communities. The study anticipates contributing experimental evidence supporting stricter occupational and environmental health measures for hydrocarbon-exposed male populations in the South South geopolitical zone.

Keywords: testicular histomorphometry, petroleum hydrocarbons, spermatogenesis, Niger Delta, endocrine disruption