A 12-week study of BHA in the cynomolgus monkey

Butylated hydroxyanisole (BHA) given by gavage to female cynomolgus monkeys on 5 days/wk for 84 days produced transient changes in selected serum chemistry and haematology parameters. Terminal observations revealed increased liver size, decreased hepatic monooxygenase activity and an increase in the mitotic index of the oesophageal epithelium. Several of these observations are similar to those reported for rodents also given BHA at or near the maximum tolerated dose. Gastroscopic evaluation of the stomach and oesophagus at monthly intervals and extensive gross and histopathological examination failed to reveal the proliferative effects seen in the forestomach of rats fed diets containing BHA.