Aflatoxins are toxic and carcinogenic substance produced by certain strains of the molds Aspergillus flavus, Aspergillus parasitic us and the rare Aspergillus nomius. There are four principle types of Aflatoxin: B1, B2, G1 and G2 in food stuff. Aflatoxin B1 is the most frequently and most toxic. To determine the Aflatoxin B1 contamination status in for nuts including Peanut, Almond, Walnut and Hazelnut, 80 samples were collected in five region in Kermanshah, Iran in 2013, then utilized for Aflatoxin B1 testing using a determination scheme consisting of enzyme-linked immune sorbent assay (ELISA). The result showed contamination in two samples of roasted Peanut in comparing with EU standard (2.5% of total samples). The highest amount of Aflatoxin B1 were found in this Peanut samples (15.744 μg/kg, 7.776 μg/kg). The interval range for Aflatoxin B1 in Peanuts were from 0.048μg/kg up to 15.744 μg/kg , for Almonds from 0.016 μg/kg up to 0.696, for Walnuts from 0. 632 μg/kg up to 1.704 μg/kg and for Hazelnuts from 0.040 μg/kg up to 0.736 μg/kg. The best average were for Almonds(0.26 μg/kg) followed by Hazelnuts (0.423 μg/kg) and then Walnuts (1.178 μg/kg) and Peanuts (1.608 μg/kg). There was no difference detected between roasted and raw samples of Almond and Hazelnut and also content of Aflatoxin B1 in tree nuts samples did not reach to maximum tolerable limit for Aflatoxin B1 in EU standard (p>0.05). Thus in future is recommended systematic and continues monitoring system for nuts.
