Reproductive and developmental toxicity of α-terpineol in Wistar rats

Alpha-terpineol (alpha-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 alpha-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 alpha-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 alpha-terpineol induced reproductive toxicities in male rats. Therefore, a detailed toxicological assessment is highly recommended.