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Updated: Jun 22, 2026
![Chemical-Induced Skin Carcinogenesis Model Using Dimethylbenz[a]Anthracene and 12-O-Tetradecanoyl Phorbol-13-Acetate (DMBA-TPA)](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F60445.jpg&w=3840&q=50)
Chemical-Induced Skin Carcinogenesis Model Using Dimethylbenz[a]Anthracene and 12-O-Tetradecanoyl Phorbol-13-Acetate (DMBA-TPA)
Published on: December 19, 2019
P-aminobenzoic acid as a sunscreen and its behaviour on the skin
G J Levee1, R M Sayre, E Marlowe
1Department of Photobiology Research, Schering-Plough Corp., Box 377, Memphis, TN 38151, U.S.A.
Abstract:
Synopsis PABA (p-aminobenzoic acid), a highly regarded sunscreening agent, has recently been shown to exhibit different absorption characteristics when applied to excised hairless mouse epidermis than when in dilute alcoholic solution. In the present study the cause of the differences was investigated. The results show that at normal application amounts, considerable quantities of randomly dispersed PABA micro-crystals exist on the skin surface. The forward scattering spectrum of PABA on skin resembled more closely that of micro-crystalline aggregates than that of PABA in solution.
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