Abstract
The aim of this study was to evaluate the biosafety of Anacardium occidentale (cashew) nut oil using male Wistar rats as model. Cashew nut oil was extracted from cashew nuts with the aid of a Soxhlet apparatus using n-hexane as solvent. Twelve male Wistar rats were randomly assigned to four groups labeled I, II, III and IV (3 rats per group). Group I served as the control group and were administered distilled water. Group II received 1.53 mL/kg of the nut oil; group III received 4 mL/kg of the nut oil while group IV received 8.13 mL/kg of the nut oil. The administrations were via the oral route. Blood samples were collected weekly for haematological examination. At the end of four weeks study period, the rats were anaesthetized and the liver and kidneys were removed for histological examination. The haematological result showed slight deviation from the normal in packed cell volume (52%), total white blood cell count (9.38 x 10³/mm³) and lymphocyte count (58.17%) in Wistar rats administered 4 to 8.13 mL/kg of the cashew nut oil, respectively yet no visible compromise of the immune system was observed. Histological analysis; however,
revealed some hepatocyte morphological lesions including mild microvesicular steatosis, kupffer cell hyperplasia, shrinkage of glomeruli, glomerular distortion, necrotic renal tubules, severe congestion and atrophy of renal tubules in rats fed 8.13mL/kg of the nut oil. In conclusion, the cashew nut oil was responsible for hepatic parenchymal and matrix alteration in wistar rats administered 8.13 mL/kg of cashew nut oil.

Key words: Cashew nut oil, Haematological parameters, Histopathology, Liver, Kidney and Wistar rats