The equivalence of assays within individual guidelines for the testing of the potential mutagenicity of chemicals: problems associated with battery selection.

Many individual Mutagenicity Guidelines contain suggested test systems with choices of such parameters as strains, cell types and even endpoint assayed. Comparisons have been made of data obtained from variants of yeast assays for the induction of mitotic recombination, in vitro assays for the induction of chromosome aberrations and assays for the induction of cell transformation. Individual test variants included in guidelines of the EEC and OECD show considerable qualitative and quantitative variability of response to potential mutagens and carcinogens. Such variability between assays within the same guideline raises considerable problems in the selection of test batteries chosen from published Mutagenicity Guidelines. Improved battery selection is dependent upon the reduction of choice within guidelines to those assays which produce consistent and reproducible results.