DDT INDUCED CHROMOSOME MUTATIONS IN MICE — FURTHER TESTING

Abstract

Laboratory mice (Mus musculus L.) were investigated for DDT induced chromosome mutations. Twenty-four brown and Balb/c strain albino mice were intraperitoneally injected with 25, 50, 100 and 250 ppm (mg/kg body weight) of DDT in peanut oil, and killed 48 h later. Controls received either no injection or peanut oil only. Karyotypes from bone marow cells of femurs were analyzed for gaps, deletions, and stickiness. Data for chromosome aberrations were taken from 200 well spread cells per animal, and mitotic indices were calculated from 1000 cells per animal. Regression of aberrations on log DDT concentrations, and Dunnett's multiple comparison test were employed to determine the effect of DDT treatments. Gaps, stickiness and mitotic indices were not significantly affected by DDT treatments, but deletions and gaps plus deletions were significantly higher or approached the significant levels at 50 ppm and higher concentrations. DDT thus appears to act as a mutagen in concentrations encountered naturally in many secondary consumers.