Allergy to tea tree oil: Retrospective review of 41 cases with positive patch tests over 4.5 years

Abstract

Tea tree oil use is increasing, with considerable interest in it being a 'natural' antimicrobial. It is found in many commercially available skin and hair care products in Australia. We retrospectively reviewed our patch test data at the Skin and Cancer Foundation Victoria over a 4.5-year period and identified 41 cases of positive reactions to oxidized tea tree oil of 2320 people patch-tested, giving a prevalence of 1.8%. The tea tree oil reaction was deemed relevant to the presenting dermatitis in 17 of 41 (41%) patients. Of those with positive reactions, 27 of 41 (66%) recalled prior use of tea tree oil and eight of 41 (20%) specified prior application of neat (100%) tea tree oil. Tea tree oil allergic contact dermatitis is under-reported in the literature but is sufficiently common in Australia to warrant inclusion of tea tree oil, at a concentration of 10% in petrolatum, in standard patch-test series. Given tea tree oil from freshly opened tea tree oil products elicits no or weak reactions, oxidized tea tree oil should be used for patch testing.

Essential Oils and Their Single Compounds in Cosmetics—A Critical Review

“…Tea tree oil reduced symptoms by 40% and was more effective than standard medications used on the skin. Surprisingly, there have been many case reports of allergic contact dermatitis, the conditions that tea tree oil may help to treat, reported as a cause of using tea tree oil [72]. One case report noted that five patients developed allergic contact dermatitis due to the topical application of tea tree oil [73].…”

Comparison of hand hygiene antimicrobial efficacy: Melaleuca alternifolia essential oil versus triclosan

“…This ensured that there was a low health risk for the subjects who were willing to participate in the trial, as well as allowing a check to be made regarding the results obtained by formulations that are already used in the healthcare settings, as in the case of triclosan, and are commercially available for use, as in the case of the soap with TTO. It is emphasized that the commercially available TTO formulation has a concentration well below that considered to be safe for human use without causing allergic effects (19) .…”

Application of essential oils as natural cosmetic preservatives

“…The composition of oil may change significantly depending on chemotypes, climate or season conditions and harvest time leading to the synthesis of different metabolites and thus different toxicity [66]. Sensitization reactions are dose-dependent, higher concentration of oil has larger allergenic potential [67,68]. Allergenic reaction develops after repeated exposure to an allergen.…”

“…The threshold of irritation varies between species and depends on oil composition. The cases of sensitization to various EOs: ylang-ylang (Cananga odorata) [69], tea tree [68,70], lemongrass [71], peppermint [72], lavender [73] and many other have been reported in literature. Most cases of allergy reported in Europe were caused by ylang-ylang and lemongrass essential oils as well as jasmine absolute [74].…”