Resumen:
Male mice dermally exposed to single or multiple treatment (5 days/2 weeks) showed that the ability of malathion to induce chromosome aberrations in somatic (bone marrow) and germ cells (primary spermatocytes) was related to the type of treatment and dose used.
Statistically significant increases of chromosome aberrations in bone marrow cells occurred after single treatment (500 and 2000 mg/kg body wt) when chromatid gaps were included and after multiple treatment (250 and 500 mg/kg) when they were excluded. No dose—response relationships were observed for either treatment. In germ cells, malathion induced a significant increase of univalents in both types of treatment but structural chromosome aberrations were induced only by multiple treatment.
Malathion induced a significant decrease of the mitotic indices in the bone marrow.