A preliminary evaluation of the performance of the Muta Mouse (lacZ) and Big Blue (lacI) transgenic mouse mutation assays.

All of the published mutagenicity data generated using the Muta Mouse (lacZ) and the Big Blue (lacI) transgenic mouse mutation assays have been re-presented in a standard format. To date, 26 chemicals have been evaluated in one or other of the assays, and eight tissues have been sampled. The present analysis should expedite the further validation of these assays. In particular, it is suggested that data on the present 26 chemicals should be consolidated rather than the generation of partial data sets on additional chemicals.