Lack of Toluene-Induced Dominant Lethals in Rats

Author Institution: Department of Biology, Central State UniversityThe mutagenic potential of toluene was investigated with the dominant lethal mutation assay. Male Sprague Dawley rats (8-10 wk old) were injected intraperitoneally for 5 consecutive days with 346 and 692 mg per kg body weight of toluene in corn oil. To analyze for the effect of toluene on several germ cell stages, each male was mated with one untreated, virgin female per week for up to 7 weeks. Females were sacrificed 14 to 17 d after insemination for analysis of their uterine contents. The total number of implantations and the number of dead and living embryos per pregnant female were determined. From these data the dominant lethal mutation index was calculated. There was no significant effect of toluene on the number of implantations (total, dead, or alive) per pregnant female per week. The different stages of spermatogenesis from late primary spermatocyte to fully mature sperm were not affected by the action of toluene as measured by the dominant lethal mutation assay. The dominant lethal mutation indices were small positive and negative percentages, suggesting that toluene did not induce dominant lethal mutations in the germ cells of male Sprague Dawley rats under the conditions tested