Limonene is a common fragrance terpene that, in its pure form, is not allergenic or is a very weak allergen. However, limonene autoxidizes on air exposure, and the oxidation products can cause contact allergy. Oxidized R-limonene has previously been patch tested in multicentre studies, giving 2-3% positive patch test reactions in consecutive patients.
Contact Dermatitis. Supplement, 2013, Vol 68, Issue 4, p. 214-23
Comparative Study; Journal Article; Multicenter Study; Research Support, Non-U.S. Gov't