Salmonella mutagenicity tests: II. Results from the testing of 270 chemicals.

This publication includes data of Salmonella mutagenicity results on 270 coded chemicals, encompassing 329 tests performed by three laboratories under contract to the National Toxicology Program (NTP). The preincubation modification of the Salmonella/mammalian microsome assay was used to test chemicals in up to five Salmonella strains in the presence and absence of rat and hamster liver S-9. With a few exceptions, inter- and intralaboratory reproducibility was good.