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Positive patch test reactions to oxidized limonene: exposure and relevance
Johanna Bråred Christensson1, Klaus E Andersen, Magnus Bruze
1Department of Dermatology, Sahlgrenska Academy at the University of Gothenburg, 405 30 Gothenburg, Sweden; Dermatochemistry and Skin Allergy, Department of Chemistry and Molecular Biology, University of Gothenburg, 412 96 Gothenburg, Sweden.
Contact Dermatitis
|August 8, 2014
Summary
Oxidized R-limonene is a frequent cause of contact allergy, impacting 36% of allergic patients. This common fragrance allergen is found in many products, highlighting significant exposure risks in daily life.
Area of Science:
- Dermatology
- Allergology
- Environmental Health
Background:
- R-Limonene, a prevalent fragrance terpene in consumer and industrial goods, readily autoxidizes.
- Oxidized R-limonene is a known contact allergen, with a multicentre study revealing positive patch test reactions in 5.2% of patients.
Purpose of the Study:
- To investigate limonene exposure in international dermatitis patients with positive reactions to oxidized R-limonene.
- To evaluate the clinical relevance of this exposure for their dermatitis.
Main Methods:
- A multicentre study involving 2900 dermatitis patients across Australia, Denmark, the UK, Singapore, Spain, and Sweden.
- Patch testing with oxidized R-limonene (3.0% in petrolatum) and a questionnaire on limonene-containing product use.
Main Results:
- Limonene exposure was identified as probably relevant to dermatitis in 36% of limonene-allergic patients.
- In Barcelona and Copenhagen, over 70% of patients had exposure deemed relevant.
- Limonene was frequently listed on product labels of affected patients.
Conclusions:
- Oxidized R-limonene is a significant and common contact allergen.
- Limonene exposure is widespread, with numerous domestic and occupational sources contributing to contact dermatitis.
- Identifying limonene in product labeling underscores its relevance in clinical allergy assessments.
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