Induction of C-type metaphases and aneuploidy in cultures of V79 cells exposed to extract of automobile exhaust particulates.

An extract of particulate matter (EPM) from gasoline engine exhaust has been tested for its effect on cell viability and plating efficiency, and its ability to produce abnormal mitotic figures and numerical chromosome alterations using the Chinese hamster cell line V79. Within a defined concentration range of EPM (0.62-4.95 micrograms/ml), no significant loss of cell viability could be observed, whereas a strong dose-dependent reduction of plating efficiency occurred. This effect is attributed to the spindle-modifying ability of EPM as could be demonstrated by the induction of C-metaphases and a highly increased mitotic index. As a result of disturbances of the spindle apparatus, EPM was found to induce aneuploidy and polyploidy in a dose-dependent manner.