For 72 samples that were positive for AFB2, the concentrations were in the range of 0.03e0.84 mg/kg, including 42 samples with the levels at 0.01e0.10 mg/kg and 30 samples with the levels at 0.10e1.00 mg/kg (Table 3). The samples only from Heilongjiang province did not contain AFB2. Shandong province had the most positive samples, with an incidence of 90%. A total of 40.6% of the samples collected from the north of China were positive for AFB2, at the level of 0.03e0.71 mg/kg. In the samples collected from the south of the country, 17.5% were positive for AFB2, at the level of
0.05e0.84 mg/kg. There was no difference observed between the north and the south in the contents of AFB2 (Table 3). Among the 200 feed samples, 53.5% of the samples were positive for AFs. The following results were obtained: 16.0% at the level of 0.01e0.10 mg/kg, 34.0% at the level of 0.11e1.00 mg/kg, and 3.5% at the level of 1.01e4.00 mg/kg. In the north, 55.6% of the samples were positive for AFs, with the concentrations between 0.03 and 3.53 mg/kg. In the south, 45% of the samples were positive; the concentrations were between 0.05 and 2.29 mg/kg. There were no differences between the north and the south in AFs concentrations of the samples (Table 3).