Duration-dependent effects of high dose of phthalate exposure on semen quality in adult male rats

OBJECTIVE: To determine the length of exposure to high doses of phthalate that might affect sperm quality in adult male Wistar rats. METHODS: Forty-two (42) adult male Wistar rats (weighing 150-200 g) were randomly assigned into six groups (n=7): Group A received 0.5 mL of distilled water - placebo - and served as controls; groups B, C, D, E and F received Phthalate (750 mg/kgbw) for 1, 3, 5, 7 and 9 weeks, respectively. The data obtained from the study was expressed as Mean ± SEM with a p-value <0.05 considered significant. The data was analyzed with one-way analysis of variance (ANOVA) followed by Tukey’s post-hoc test using GraphPad Prism, version 8. RESULTS: The results showed a statistically significant (p<0.05) decrease in testicular weight in the rats exposed to 750 mg/kg of phthalate for 3, 5, 7 and 9 weeks when compared with the controls. Sperm count, motility and viability were also significantly (p<0.05) reduced, while sperm cells with abnormal morphology had increased counts in the groups exposed for 3, 5, 7 and 9 weeks when compared with controls. Serum zinc and magnesium were also significantly reduced (p<0.05) in the subjects treated for 1, 3, 5, 7 and 9 weeks when compared with controls. CONCLUSIONS: The dosage of phthalate adopted in this study was deleterious to testicular function when rats were exposed to it for as short a period as three weeks.