Self-medication of rheumatic complaints in the upper arm, by one woman, and of a
lipoma on the thigh, by another, with pure
laurel oil caused within two weeks severe
contact dermatitis and swellings far from the point of application.
Sesquiterpene lactone, contained within
laurel oil, proved to be the cause of the induced contact
allergy. Since the acquired specific
hypersensitivity of the
eczema type is directed primarily against the alpha-methylene group of the
lactone, cross-reactions were observed against a large number of other plans which are botanically unrelated but contain substances of a similar class. Those allergic to
laurel oil should therefore avoid many
cosmetics, articles of hygiene, foods, drinks and medicinal preparations which contain herbs, as well as gardening, certain cut flowers and perfumes, especially those of the family Compositae. The present trend "back to nature" makes further sensitizations against
laurel oil likely. This would seem to justify the inclusion of these substances among the group of potentially harmful environmental and occupational products.