Reproductive and developmental toxicity of α-terpineol in Wistar rats

Alpha-terpineol (α-T) is a type of monoterpenoid alcohol commonly present in essential oils, it contributes to a pleasant floral fragrance similar to that of lilacs. This research aimed to evaluate the impact of α-terpineol on the reproductive functions of both male and female rats, including gonadal activity, mating behavior, conception, conceptus development and parturition. Six male and female Wistar rats per group received α-terpineol through gavage at doses of 0, 75, 150 and 300 mg/kg/day. The study revealed changes in body weight gain inhibition, food consumption, azoospermia, decreased testosterone levels (0.7 ± 1.61 ng/mL, 0.7 ± 2.30 ng/mL) as well as histopathological variations in testis and epididymis among males exposed to doses of 150 and 300 mg/kg/day. Moreover, this exposure led to significantly decreased serum T4 levels in both adult males (21.85 ± 12.68 ng/mL, 16.20 ± 9.15 ng/mL) and dams (11.24 ± 12.37 ng/mL, 9.48 ± 11.74 ng/mL) at the dose range of 150 and 300 mg/kg/day without affecting TSH concentrations. In summary, the present study showed that α-terpineol induced reproductive toxicities in male rats. Therefore, a detailed toxicological assessment is highly recommended.