Effects of butylated hydroxytoluene alone or with diethylnitrosamine in mice

Abstract

Mice (18 months old) given butylated hydroxytoluene (BHT) at a dietary level of 0·75% for 16 months had 63·6% of lung tumours compared with 24·0% in controls. Mice given dietary BHT as well as diethylnitrosamine (DENA) in the drinking-water (average total intake 330 mg DENA/kg) had more lung tumours per mouse (4·0) than did the controls or those given DENA alone or BHT alone (1·4–2·2). The incidence of reticulum-cell sarcomas in mice killed at 12 months of age in the group treated with BHT plus DENA exceeded control values (52·6 and 22·7%, respectively), while the incidence in groups receiving DENA alone or BHT alone was not significantly different from that in controls. At 18 months, the incidence of reticulum-cell sarcoma in both groups given BHT was significantly less than in the groups not receiving BHT. At 18 months of age, a higher percentage of squamous-cell carcinomas was seen in the forestomach of mice given BHT plus DENA than in mice receiving DENA alone. The production of cysts within the liver parenchyma after DENA treatment also appeared to be potentiated by BHT treatment.