There is a strong safety concern related to aromatherapy as they are potentially toxic to the skin with adverse effects to other organs if used undiluted or with a wrong combination.
There have been instances of phototoxic reactions with citrus peel oils such as lime and lemon.
Lavender oil and tea tree oil has been reported to cause gynaecomastia in prepubescent boys. Pediatric endocrinologists at the University of Cambridge say that these two oils are estrogenic in nature.
Essential oils are potentially allergic to the skin and can cause severe reactions on the body, if not used in the right way.
Aroma therapeutic oils should not
be taken as a food product and can be dangerous if ingested, an example is eucalyptus oil, which has earlier been reported to cause severe clinical symptoms and poisoning. Cedar, sage, hyssop and thuja are liable to cause hepatic damage and seizures.
Certain essential oils should be avoided with other conventional pharmaceutical medications as they can have a cumulative effect, such as the topical application of sweet birch and wintergreen which is responsible for causing bleeding disorders and thinning of the blood in users taking the anticoagulant warfarin. This is because of both these oils contain methyl salicylate as a component.
Pregnant and lactating women should avoid aromatherapy.