Dose response in butylated hydroxyanisole induction of forestomach carcinogenesis in F344 rats.
Groups of 50 6-week-old male F344 rats were given a powdered diet containing 0, 0.125, 0.25, 0.5, 1, or 2% butylated hydroxyanisole [(BHA) CAS: 25013-16-5] for 104 weeks. The highest dose--2% BHA--induced significant increase in the incidence of squamous cell carcinoma of the forestomach. Papillomas of the forestomach developed in 20 and 100% of the rats given diets containing 1 and 2% BHA, respectively. The incidence of epithelial hyperplasia of the forestomach increased with the increased BHA doses, to 100% incidence at the highest dose. Thus the incidences of proliferative and neoplastic lesions of the forestomach were dose dependent.