The action of the herbicide paraquat on somatic and germ cells of mice.

The genotoxic potential of paraquat was evaluated in mouse somatic (bone marrow) and germ (spermatozoa) cells. Two exposure schedules were conducted: single and multiple treatment. Only for multiple treatment was an increased frequency of chromosomal aberrations observed. In germ cells, paraquat induced an increase of sperm-shape abnormalities when the animals were treated at three stages of cell development: spermatozoa, spermatid and preleptotene spermatogonial cells. These toxicogenetic effects might be attributed to the ability of paraquat to generate oxygen free radicals.