As part of our investigation into mutagenic effects of environmental compounds, we studied chemicals allowed as ingredients of cosmetics according to the guidelines of the Council of the European Communities (27 July 1976). We used three systems, the Salmonella/microsome test, the Basc test on Drosophila and the micronucleus test on mouse bone marrow. Of the 31 chemicals tested, 15 were mutagenic in the Ames test; and of these, 5 were also mutagenic in the Basc test and 2 in the micronucleus test.