2,[3]tert-butyl-4-hydroxyanisole does not reduce SCE induction by benzo(a) pyrene in bone marrow cells of C57BL/6 mice.

Recently, a number of publications have suggested that bone marrow cytogenetics may be used to detect anticarcinogenic or antimutagenic activity. In this work, 0.75% 2,[3]-tert-butyl-4-hydroxyanisole (BHA), fed in the diet for 2 weeks, was tested for its ability to reduce the frequency of benzo(a)pyrene (BP)-induced SCE in mouse bone marrow. C57BL/6 male mice, were injected i.p. with BP at 0, 33, 67, and 100 mg/kg body weight. The mean SCE/chromosome +/- s.e.m. for animals on control diet was 0 mg/kg, 0.108 +/- 0.005; 33 mg/kg, 0.225 +/- 0.011; 67 mg/kg, 0.289 +/- 0.012; 100 mg/kg, 0.311 +/- 0.013. The mean SCE/chromosome +/- s.e.m. for animals on the 0.75% BHA diet was 0 mg/kg, 0.105 +/- 0.006; 33 mg/kg, 0.224 +/- 0.009; 67 mg/kg, 0.262 +/- 0.013; 100 mg/kg, 0.326 +/- 0.012. There are no significant differences between animals on the control and BHA diets. Excretion of BP in urine over a 72 hr time period was significantly increased in animals on the BHA diet, at both low and high doses. Water-soluble metabolites accounted for all of this increase. It appears that bone marrow is not a good model for the gastrointestinal tract, and that short-term assays for anticarcinogens or antimutagens are more likely to be predictive if they are done in the target organs.