Toxicity study of Bixa orellana Linn. extract, produced by Medicinal Plant Research Institute was investigated. The maximum dose of 16.0 g/kg extract was orally administered to mice and it was shown that the extract cause no acute toxic signs and no death. Oral subacute toxicity study in five group of Wistar rats consisting of water control and four extract-treated groups at the doses of 0.24, 2.4, 12.0 and 60.0 mg/kg/day revealed that the extract did not cause any toxic sign and there was no alteration on bodyweight, food consumption, relative organ weight and blood chemistry values. The increases of neutrophil in male rats receiving the extract at the dose 12.0 and 60.0 mg/kg/day were minor change and still within normal range. Necropsy results showed no gross pathological changes of visceral organs. Histopathology revealed no abnormalities in any organs except male rats receiving the highest dose of extract had higher incidence of mild fatty change. Therefore, application of the extract for coloring agent at high concentration or overdose should be avoided and the amount of active ingredients (bixin and norbixin) in the extract should be taken into account for appropriate concentration in each food stuff as reported in other countries.

Key words: Bixa orellina, Toxicity