Comparison of percutaneous absorption of fragrances by humans and monkeys.

The percutaneous absorption of two cosmetic fragrance materials, safrole and cinnamyl anthranilate, as well as of cinnamic alcohol and cinnamic acid, has been measured at occluded and non-occluded application sites. Absorption values were determined in the rhesus monkey in vivo. Absorption through human skin was measured by using excised skin in diffusion cells. Because of the insolubility in water of safrole and cinnamyl anthranilate, a nonionic surfactant solution (6% oleth 20) was used in the receptor chamber of the diffusion cell in order to facilitate the partitioning of the compounds from the skin into the receptor fluid. The relative volatility of the compounds was determined in order to aid in the interpretation of the absorption results. The greatest difference between in vivo and in vitro absorption values occurred with safrole, which was the least well absorbed and the most volatile compound. Cinnamic acid absorption through non-occluded human skin (17.8 +/- 4.9%, mean +/- SEM) was significantly lower than through monkey skin (38.6 +/- 8.3%). The values for absorption through human and monkey skin did not differ significantly for cinnamyl anthranilate (24.0 +/- 5.1% v. 26.1 +/- 2.3%) or cinnamic alcohol (33.9 +/- 7.3% v. 25.4 +/- 4.4%). Occlusion of the skin resulted in greater permeation of all of the compounds; a significant difference in permeability between the two types of skin occurred only with safrole. The fragrances were absorbed well, but their volatility must be considered in a toxicity evaluation. There was reasonable agreement between the values obtained from the studies of the human skin in vitro and the monkey skin in vivo.

Allergic contact photodermatitis to para-aminobenzoic acid.

Allergic photocontact dermatitis developed in a patient to a commercial sunscreen preparation containing para-aminobenzoic acid (PABA) in an alcohol base. Photopatch testing showed photosensitivity to PABA. Sensitization could only be detected when PABA was tested in an alcohol vehicle; a photopatch test to PABA in petrolatum was negative.

Immunofluorescence testing in a bullous skin disease of a dog.

A chronic skin disease in a dog, which resembled a pemphigus-like condition, was studied histologically and by direct immunofluorescence testing. Histologic examination revealed a bullous disorder and was a useful diagnostic tool; however, direct immunofluorescence testing showed the disease to be equivalent to bullous pemphigoid of man.