Oral toxicity assessment of annatto in rats

Abstract

The aim of the investigation was to determine the possible health hazards of bixin (30%) from annatto (Bixa orellana L.) origin to rats. A concentration of 0.01±0.006%/day of bixin in corn oil was administered to 20 Wistar rats (10 per sex), through the oral route (gavage) over a period of 13 weeks. A group of untreated animal (10 per sex) acting as a control (corn oil) was used for comparision. Body weight, body weight gain, feed consumption and feed efficiency were determined. The health of the animals was checked. At the end of the study a biochemistry (glucose, creatinine, total cholesterol, triglyceride, asparagine transaminase and g-glutamyl transaminase) and hematological examination was carried out. All the animals were subjected to a gross-pathological assessment followed by liver, kidney, adrenals, spleen and tests weight. A histopathological analysis (liver and kidney) was performed. From the weight parameters clinical, clinical chemistry and haematology, necroscopy and histology viewpoints, it can be said that annatto, under the chosen test condition, was no toxic to the rat.