This reserch was carried out to identify the transplacental genotoxicity of automobile exhaust emission in mice. The mice were divided into six groups by the operational condition of diesel engine (D1146) such as speed and load.
For the investigation of those effects, female mice of ICR strain were used. The benzeneethanol extracts of diesel exhaust emission were injected intraperitonially at 25mg/kg or 50mg /kg doses respectively. Twenty hours after injection, the mice were sacrificed.
To evaluate the transplacental genotoxicity, the authors carried out the micronuclei test,
induction of sister chromatid exchange (SCE), and histopathological examination of mouse fetus.
1. As for the appearance rate of micronucleated cells among polychromatic erythrocytes (MNPCE) in fetal liver, the idling group showed 5.4 times as high a rate as control group. The groups of 1,500 rpm and 2,000 rpm showed higher rate than control group by about two or three times. And there was no significant difference between 50% load and 10056 loads.
2. The average SCE frequency was the highest in idling group, which showed 2.3 times higher rate than control group. These results were similar to the appearance rate of MNPCE.
3. In the fetal liver and lungs of idling group, parenchyme congestion and hemorrhage were
observed. And 1,500 rpm group and 2,000rpm group showed slight congestion of liver and lungs.
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