Medina, A. DeBrugerolle De Fraissinette, C. Elsaesser, V. Picarles, N. hartmann, O. Grenet, S. Chibout and M. Kolopp. (2000). Investigation of Skin Phototoxicity Potential Using an In Vitro Human Epidermis Model (SkinEthic). The Toxicologist. 54(1). Abstract # 686.

8-methoxypsoralen - 00298-81-7; tetracycline - 00060-54-8; promethazine - 00060-87-7; 6-methylcoumarin - 00092-48-8; sodium lauryl sulfate - 00151-21-3

The present study evaluated the suitability of the human reconstituted epidermis model SkinEthic (registered trademark) for the assessment of the in vitro phototoxic potential of topical products. The phototoxic compounds 8-methoxypsoralen, tetracycline, promethazine and 6-methylcoumarine (weak phototoxicity), and the non-phototoxic compound sodium lauryl sulfate were tested. The response of the tissue to the application of the test articles in the presence and absence of UV light, was analyzed in terms of viability (LDH release), proinflmmatory activity (IL-8 and IL-1 alpha release and mRNA expresion) and morphology (histopathological analysis). Two different prediction models were used: the Photo-Irritancy Factor (PIF) and the Mean Photo Effect (MPE). All the non-phototoxic and phototoxic products tested were correctly classified. Due to poor skin penetration, tetracycline was identified as phototoxic only after application in the culture medium, and not via the topical route. These results indicate that the method is appropriate for the investigation of the phototoxic potential of products intended for topical administration. A simplified version based on the determination of LDH release is recommended for high throughput screening purposes (simple differentiation between phototoxic and non-phototoxic products). On the other hand, the complete version of the protocol, including the parameters, seems to be necessary for the evaluation of weak phototoxic products.