Background:
The Eucalyptus globulus extractions have been used by the traditional
healers to treat diseases in the study area. Our previous study revealed that the essential
oil has antimicrobial and antifungal activity. This study determined phytochemical analysis,
skin irritation, acute and subacute toxicity of Eucalyptus globulus essential oil in mice
and rats.
Methods:
The phytochemicals were analyzed using GC-MS mass spectrometry. The acute
toxicity study was determined at three dose levels of 1500 mg/kg, 1750mg/kg, and 2000
mg/kg. The essential oil limit test at a dose of 1000 mg/kg was administered to mice for 28
consecutive days for sub-acute toxicity study. The mice mortality, behavioral change, injury
and other signs of illness were recorded once daily. Biochemical parameters were evaluated.
Liver and kidney were analyzed for histopathological analyses. The 5% ointment formulation
was applied to the rat skin to determine skin irritation effects.
Results:
The Eucalyptus globulus essential oil showed no effect on the mice at a dose of
1500mg/kg and below, but caused signs of toxicity and death at a dose of 1750mg/kg and
above compared to the controls (p<0.05). The LD50 value was 1650 mg/kg. There was no
significant difference (p > 0.05) in the body weights, gross abnormalities of the organs and
biochemical parameters compared to the control at 1000 mg/kg subacute toxicity study. No
histopathological changes were detected in the organs tested. The 5% ointment formulation
did not show any abnormal skin reaction.
Discussion:
In the present study, the Eucalyptus globulus essential oil was comparable with
other studies in terms of both chemical composition and its effects on sub-acute and topical
application.
Conclusion:
This toxicity study demonstrated that Eucalyptus globulus essential oil is nontoxic
at a relatively lower concentration.