4-week range-finding and 1-year oral toxicity studies of sucrose acetate isobutyrate (SAIB) in the cynomolgus monkey.

Sucrose acetate isobutyrate (SAIB) is used as an emulsion stabilizer in citrus-based soft drinks. A 4-week range-finding study and a 1-year chronic toxicity study were conducted to determine the tolerance and effects of this food additive in cynomolgus monkeys. SAIB was administered by gavage in corn oil solutions to groups of one monkey of each sex in the range-finding study and four monkeys of each sex in the 1-year study. The dose levels employed in both studies were 0, 500, 1450 and 2400 mg/kg body weight. Control monkeys were given corn oil by gavage. Based on the range-finding study, the 2400 mg/kg body weight dose level of SAIB was considered to be the highest dose of SAIB in corn oil that would be tolerated in a long-term study. No differences were observed between treated and control animals in either study with respect to body weight gain, clinical chemistry, haematology, organ weights, gross necropsy or light microscopy findings that could be attributed to SAIB treatment. Results of specific tests of hepatobiliary function in the 1-year study, including serum enzymes, bilirubin and bile acids, bromsulfophthalein retention and electron microscopic studies of the liver, were also negative. It was concluded that the highest dose level fed, 2400 mg/kg body weight, was the no-observed-adverse-effect level (NOAEL).