The aim of this work was to determine the contamination levels of raw and roasted cashew nuts sold in Masasi and Newala districts of Mtwara region in Tanzania. A total of 60 samples including 40 roasted (24 samples from Newala and 16 from Masasi) and 20 raw samples (12 from Newala and 8 from Masasi) were collected. Determination of total aflatoxins levels in raw and roasted cashew nuts samples was carried out by immune affinity high performance liquid chromatography (HPLC). The levels of contamination ranged from not detected (less than Limit of Quantification) to 3.29 µg/kg for both aflatoxin B1 and total aflatoxin in the cashew nuts samples. None of the samples had total aflatoxins contamination greater than the recommended maximum residues of 4 µg/kg set by European Commission (2010) or 10 µg/kg set by FAO and WHO (1995). About a quarter (38%) of the samples had total aflatoxins less than limit of quantification. All roasted cashew nut samples were found to have total aflatoxins less than 3 µg/kg while about 86% of raw cashew nut samples had total aflatoxins less than 3 µg/kg.
Keywords: Aflatoxin, cashew nuts, contamination, Mtwara, Tanzania