Castor oil is a natural oil derived from the seeds of the castor bean, Ricinus communis. It is comprised largely of
triglycerides with a high ricinolin content. Toxicity studies with
castor oil were performed by incorporating the material at concentrations as high as 10% in diets given to F344/N rats and B6C3F1 mice of both sexes for 13 weeks. Genetic toxicity studies also were performed and were negative for mutation induction in Salmonella typhimurium, for induction of sister chromatid exchanges or
chromosomal aberrations in Chinese hamster ovary cells, and for induction of micronuclei in the peripheral blood erythrocytes of mice evaluated at the end of the 13-week studies. Exposure to
castor oil at dietary concentrations as high as 10% in 13-week studies did not affect survival or
body weight gains of rats or mice (10 per sex and dose). There were no biologically significant effects noted in hematologic analyses in rats. Mild increases in total
bile acids and in serum
alkaline phosphatase were noted at various times during the studies in rats receiving the higher dietary concentrations of
castor oil. Liver weights were increased in male rats receiving the 10% dietary concentration and in male and female mice receiving diets containing 5% or 10%
castor oil. However, there were no histopathologic lesions associated with these liver changes, nor were there any compound-related morphologic changes in any organ in rats or mice. No significant changes were noted in a screening for male reproductive endpoints, including sperm count and motility, and no changes were observed in the length of estrous cycles of rats or mice given diets containing
castor oil. Thus, no significant adverse effects of
castor oil administration were noted in these studies. Synonyms: Ricinus Oil, oil of Palma Christi, tangantangan oil, phorboyl, Neoloid.