Results
Out of total 275 rice samples were analyzed, aflatoxin B1 and/or B2 were detected in 211 (76.72%)
among which 203 (73.82%) had only AFB1 with the mean and standard deviation of 2.3±10.21 ppb
while other 8 (2.91%) were contaminated with AFB2 and AFB1 of 1.38±2.7 ppb and 2.99±1.56 ppb respectively. AFG1 and AFG2 were not detected in tested rice samples. None of the aflatoxins were found in 64 (23.27%) samples. Regarding the Iranian and European standards for Maximum Tolerated Levels (MTL) (26), we adjusted two levels of AFT to level 1 which was for AFT concentration < 30 ppb, < 4 ppb and level 2 with ≥ 30 ppb, ³ 4 ppb. AFB1 level of 5 samples (1.82%) were higher than the mentioned MTL of 5 ppb, while 3 of those samples (1.09%) had AFB1 level higher than 30 ppb. The results of HPLC assay before and after treatment of rice samples with 1N CA are summarized in Table 1.