No abstract

Lifetime ingestion by rats of 0.2 mg/kg/day of hexachlorobutadiene caused no discernible ill effects. Slight degrees of primarily renal toxicity occurred with 2 mg/kg/day; 20 mg/kg/day caused multiple toxic effects, including renal tubular neoplasms.

The effect of handling mice by the tail or by the body on serum alanine transaminase (ALT) activity was investigated in normal mice and in mice pretreated with a known hepatotoxin. In normal mice, the mean ALT activity 1 h after grasping the body was almost four times greater than in the control (not-handled) and tail-handled groups. However, when ALT analyses were repeated 1 week later, all groups were equivalent. In mice given a hepatotoxic dose of 30 mg kg-1 carbon tetrachloride, the mean ALT activity was approximately three times greater in mice handled by the body than in mice grasped by the tail only. Handling mice by the body may reduce the usefulness of ALT activity as a measure of hepatotoxicity.

Sister chromatid exchanges (SCE) were analyzed in peripheral blood lymphocytes from a select group of 71 healthy men, 56 nonsmokers and 15 cigarette smokers. In addition to estimating baseline SCE, data were examined to seek relationships of SCE frequencies to age and smoking. The baseline value of 7.53 SCE per cell from the 56 nonsmokers was within the range (5.60 to 9.10 SCE/cell) reported for other human populations. No relationship was found between the mean SCE frequency per cell and age. However, a significant increase in the SCE mean value was observed in smokers as compared to nonsmokers. The results of this study are compared with those of other reports on SCE effects of age and smoking.