Primary dermal irritation study of oregano oil in rabbits

The present study was carried out to investigate the skin irritation potential of oregano oil in rabbits. A volume of 0.5 ml of test article was applied to intact and abraded skins, respectively, for 24 h in 6 healthy male New Zealand White rabbits. Parameters measured during 72 h observation period were mortality, clinical signs, body weight changes, and local irritation. Treatment-related toxic symptoms, as evidenced by anorexia and decreased locomotor activity, were observed in all rabbits tested. Two rabbits out of the 6 total died on day 2 after the application of test article due to treatment-related toxicity. The mean body weight of test animals decreased progressively during the 72 h observation period. All animals showed very slight edema at 24 h and then recovered at 72 h. These animals also showed very slight to severe erythema and/or slight eschar formation at both 24 h and 72 h. The eschar formation induced by oregano oil was not recovered at the end of additional 11-day recovery period. Based on these results, it was concluded that a single dermal application of the undiluted oregano oil caused an increased incidence of clinical signs and death and a decrease in the body weight and showed a primary irritation index score of 2.79 indicating moderate irritation.

토끼에서 oregano oil의 일차 피부 자극시험