Registration Dossier

Toxicological information

Carcinogenicity

Currently viewing:

Administrative data

Description of key information

Key value for chemical safety assessment

Additional information

2-year mouse carcinogenicity study

This study was conducted to assess the carcinogenicity of sucrose acetate isobutyrate (SAIB) when fed to 86C3F1/CrlBR (86) mice for at least 104 weeks. A total of 250 males and 250 females were assigned at random to 5 groups (50/sex/group) that received diets containing 0.0, 0.0, 1.25, 2.5, or 5.0 g SAIB/kg body weight/day (g/kg). A baseline evaluation (including clinical pathology and gross necropsy) was done on 10 animals/sex before the initiation of treatment. During the study, all animals were observed for signs of toxicity, moribundity, and death. Physical examination, body weight, and food consumption data were collected weekly. Hematology parameters were evaluated for 15 animals/sex after 26, 52, 78, and 104 weeks for animals given 0.0 (Group 1) or 5.0 g/kg. A necropsy was done on animals that died or were sacrificed in a moribund condition during the study. After 104 weeks of treatment, necropsies were done on all surviving animals. The animals were examined macroscopically, representative organs were weighed, and representative tissues were placed in fixative. Tissues collected from animals in the control and high-dose groups and from the animals that died or were sacrificed in a moribund condition were examined microscopically. Macroscopic lesions, lungs, livers, and kidneys from all animals were examined microscopically. There were no treatment-related antemortem observations or deaths and no treatment-related differences in body weight, body weight gain, food consumption, or hematology data. Kidney weights were significantly lower for males given 2.5 or 5.0 g/kg, and kidney-to-body weight percentages were lower for males given 5.0 g/kg. Kidney weight differences for males given 5.0 g/kg were considered treatment-related. There were no other treatment-related differences in organ weights or macroscopic or microscopic observations. There was an increase in the incidence of hyperplasia of perivascular and peribronchial lymphoid tissue for females given SAIB, but this change was not considered to be toxicologically important. Based on the results of this study, the no-observable-effect level for SAIB when fed to 86 mice for 104 weeks is 2.5 g/kg body weight/day.

2-Year Rat carcinogenicity study

This study was conducted to assess the carcinogenicity of the test material, sucrose acetate isobutyrate (SAIB), when fed to COF®(F-344)/CrlBR (Fischer) rats for at least 104 weeks. A total of 250 males and 250 females were assigned at random to 5 groups (50/sex/group) that received diets containing 0.0, 0.0, 0.5, 1.0, or 2.0 g SAIB/kg body weight/day (g/kg). During the study, all animals were observed for signs of toxicity, moribundity, and death. A baseline evaluation (including clinical pathology and gross necropsy) was done on 10 animals/sex before initiation of treatment. Physical examination, body weight, and food consumption data were collected weekly. Hematology parameters were evaluated for all surviving animals after 104 weeks. A necropsy was done on animals that died or were sacrificed in a moribund condition during the study. After 104 weeks of treatment, necropsies were done on all surviving animals. The animals were examined macroscopically, representative organs were weighed, and representative tissues were placed in fixative. Representative tissues collected from animals in the control and high-dose groups and from the animals that died or were sacrificed in a moribund condition were examined microscopically. Macroscopic lesions, as well as, lungs, livers, and kidneys from all animals were examined microscopically. There were no treatment-related antemortem observations or deaths, and no treatment-related clifferences in body weights, body weight gains, or food consumptions were observed. There were no treatment-related changes in hematology variables and no treatment-related macroscopic or microscopic findings. The neoplastic and non-neoplastic changes noted in this study were typical of the changes seen in long-term studies with Fischer rats. The incidences of tumors were similar among control and treated groups. Based on the results of this study, the no-observable-effect level for SAIB when fed to Fischer rats for 104 weeks is greater than 2.0 g/kg body weight/day.

Justification for classification or non-classification