title: Allergic contact dermatitis from 12-hydroxystearic Acid and hydrogenated castor oil.
abstract: A 34-year-old male experienced severe allergic contact dermatitis from 12-hydroxystearic acid in a lip balm and from hydrogenated castor oil in an underarm deodorant. He also had a positive patch-test reaction to bis-diglyceryl polyacyladipate-2, which is present in the implicated lip balm and which itself contains 12-hydroxystearic acid. He was also incidentally found to have contact allergy to ricinoleic acid and castor oil. Ricinoleic acid is the principal fatty acid in castor oil, whereas 12-hydroxystearic acid is the principal fatty acid in hydrogenated castor oil. These two fatty acids are each 18-carbon 12-hydroxylated fatty acids, differing only in degree of saturation. The lack of patch-test reactivity to the analogous nonhydroxylated fatty acids, stearic acid (C18:0), and oleic acid (C18:1) indicates that 12-hydroxylation was required for allergenicity in this patient. In addition, serial dilution testing demonstrated that saturation of the hydroxylated C18 fatty acid enhanced its allergenicity.
authors: University of California, San Diego, San Diego, CA, USA.
authors: Daniel W
authors: DW
authors: Shaw
mesh_terms: D000328:Adult; D002368:Castor Oil / Q000009:adverse effects*; D003358:Cosmetics / Q000009:adverse effects; D017449:Dermatitis, Allergic Contact / Q000175:diagnosis / Q000209:etiology*; D005227:Fatty Acids / Q000009:adverse effects*; D006801:Humans; D008297:Male; D010328:Patch Tests; D012277:Ricinoleic Acids / Q000009:adverse effects; D013229:Stearic Acids / Q000009:adverse effects*
chemical_list: C539357:12-hydroxy stearic acid; D003358:Cosmetics; D005227:Fatty Acids; D012277:Ricinoleic Acids; D013229:Stearic Acids; D002368:Castor Oil; C030521:ricinoleic acid