Gasoline Inhalation Inhibits Reproductive Function in Male Wistar Rats Across: A Transgenerational Study

Abstract

The chronic exposure and inhalation of gasoline products in the present society, especially in the Southern part of Nigeria (Niger Delta), and the fact that this gasoline has been reported to be harmful to human health, is a source of concern. This study investigated the effect of gasoline inhalation on hormone profile and semen analysis in male Wistar rats: two generation study. Male and female Wistar rats were exposed to gasoline inhalation at doses of group A (control) nil, groups B- G had 20ml/hr/day, 20ml/2hr/day, 20ml/3hr/day and 40ml/hr/day, 40ml/2hr/day, 40ml/3hr/day respectively for 14 weeks parent generation (F0) and 16 weeks first generation (F1) before mating, continued throughout mating, pregnancy, lactation until weaning of second generation (F2). Blood samples collected and analysis were conducted on hormone profile, and semen analysis were accessed. Statistical analysis was conducted via mean standard deviation with R computing environment, version 4.3.3. Results:Testosterone showed significant progressive decline in exposed groups from B (4.01 ± 0.07) , D (2.97 ± 0.05), E (1.84 ± 0.05), F (1.55 ± 0.04), through G (1.33 ± 0.01) (p < 0.001), In F1, groups B through G displayed significantly lower testosterone levels compared to their respective F0 counterparts (p < 0.001 for all). In F0, group E had the highest FSH, while C and D had the lowest, all significantly different. In F1, FSH values were higher but F–G had slightly lower values. There a significant increase in FSH from F0 to F1 for B, C and D conversely, E, F, and G showed a significant decrease in FSH from F0 to F1. In the F0, all LH values significantly declined compared to A. In F1, groups B -D also showed a significant generational increase. There was significant deterioration of all measured sperm parameters, with severity increasing across exposure groups (B–G). Significant intergenerational declines were observed in several parameters. This study contributes novel evidence supporting that chronic gasoline inhalation poses a great risk with the adverse effects being heritable across generations. This has significant implications for public health and occupational safety, particularly in populations chronically exposed to gasoline fumes.