EEC COLIPA PROJECT ON IN-VITRO PHOTOTOXICITY TESTING - FIRST RESULTS OBTAINED WITH A BALB C 3T3 CELL PHOTOTOXICITY ASSAY/

In a joint validation project eight laboratories from the European Cos metic Industry Association (COLIPA) as well as FRAME (England) and ZEB ET (Germany) are trying to develop validated in vitro methods to be in corporated into new international guidelines for acute phototoxicity t esting. The first stage of the study involved selection of the most pr omising in vitro phototoxicity tests for further validation. 20 chemic als with known phototoxic properties (12 phototoxins, four UV-absorbin g non-phototoxins and four non-UV absorbing non-phototoxins) were test ed under identical conditions of UV exposure conditions (sun simulator , UVA 5 J/cm(2)) in a standardized cytotoxicity assay with Balb/c 3T3 fibroblasts (endpoint: neutral red uptake, NRU). 19 of the 20 chemical s were correctly classified by the 3T3 NRU phototoxicity test, and the refore, this simple assay for phototoxicity seems very promising and s hould be validated further.