Micronuclei in red blood cells of the newt Pleurodeles waltl Michah: induction with X-rays and chemicals.

Pleurodeles waltl, a typical long-tailed amphibian (Urodela) is proposed as a new animal for genetic toxicological studies. X-Rays and various clastogenic substances cause the formation of clearly visible micronuclei in the red blood cells (RBC). The proportion of cells with micronuclei was determined from blood smears of larvae after irradiation or after having been kept in water containing the substances to be studied. A dose-effect curve was established for X-irradiation. The 6 following substances were tested by this method: benzo[alpha]pyrene, carbaryl, N-nitrosocarbaryl, aziridine, caffeine and formaldehyde. Formaldehyde was the only substance tested that did not bring about formation of micronuclei in the RBCs. The results were compared with data already obtained by other methods of toxicology. This method should allow a cytogenetic test to be developed for the detection of clastogenic substances in aqueous media.