Cytogenetic effects induced by organophosphorus pesticides in mouse spermatocytes

Male mice (Q strain) received a single i.p. injection of 14 organophosphorus compounds, including 11 insecticides, administered on separate occasions. After a recovery period of 10 to 15 days, the cytogenic effects were analyzed in primary spermatocytes at diakinesis-metaphase I corresponding to the treatment of A4-B type spermatogonia. At the highest tolerated dose, trimethylphosphate (1000 mg/kg), triethylphosphate (300 mg/kg), dichlorvos (10 mg/kg), methylparathion (10 mg/kg), ethylparathion (10 mg/kg), ethylparaoxon (0.3 mg/kg), fenitrothion (1000 mg/kg), methylbromophos (1000 mg/kg), ethylbromophos (1000 mg/kg), dimethoate (10 mg/kg), malathion (300 mg/kg), methylazinphos (1 mg/kg), ethylazinphos (1 mg/kg) and trichlorfon (100 mg/kg) did not produce chromosome damage.