Inductest and spermatest in genetic toxicology testing.

Bacterial strains have been especially devised to measure the ability of chemicals to induce phage development. This type of test named Inductest, responds in general to DNA damaging agents. Metabolic activation can be used and good sensitivities are achieved. Variations of the Inductest exist: some have short time responses (1 h or less) or allow to look at phage mutagenesis as well. Some compounds elicit a response in Inductest and not in the bacterial mutagenesis assay (Mutatest). The reverse is also true and may be more frequent. The sperm abnormality assay (Spermatest) consists in examining by visual scoring of sperm shape if an agent is able to damage in vivo mammalian germ cells. Such agents are in general able to interfere with the normal differenciation of sperm cells so that genetic damage is probably not the only end point of the assay. The spermatest yields false negative but few false positive for carcinogenicity. It can be used directly to monitor human populations. Both tests, have probably not yet reached their full development.