Heritable translocations induced by inhalation exposure of male mice to 1,3-butadiene

Previously, we reported that dominant lethal mutations were induced in spermatids after inhalation exposure of male (102/El × C3H/El)F₁ mice to 1300 ppm of 1,3-butadiene on 5 days for 6 h per day (exposure dose 39 000 ppm h). The same inhalation exposure was given to male C3H/El inbred mice which were mated to inbred line 102/El females 8–14 d after the end of exposure. Male and female F₁ hybrid progeny were tested for the presence of heritable translocations by observation of litter sizes and by cytogenetic analyses in meiotic and somatic cells. 1,3-Butadiene induced heritable translocations in late spermatids. The translocation frequency after 1,3-butadiene exposure to 39 000 ppm h was 2.7% (16 translocation heterozygotes among 599 F₁ offspring). This frequency is 54 times higher than the historical control frequency (0.05%; 5 translocation heterozygotes among 9500 F₁ offsping). Thus, 1,3-butadiene causes heritable germ cell effects in mice.