Occurrence of five 8-ketotrichothecene mycotoxins in organically and conventionally produced cereals collected in Korea

A total of 188 cereal samples, consisting of conventionally (n = 99) and organically (n = 89) produced rice, brown rice, barley and corn were analyzed by gas chromatograph-electron capture detector for five 8-ketotrichothecenes (deoxynivalenol (DON), nivalenol (NIV), 3-acetyldeoxynivalenol (3ADON), 15-acetyldeoxynivalenol (15ADON) and fusarenone-X (FUS-X)). Recoveries of these five toxins spiked at 200 μg/kg in barley and corn ranged from 73% to 96% with a relative standard deviation of 2.6%-10.8%. The overall incidence of DON, NIV, 3ADON, 15ADON and FUS-X was 38%, 40%, 14%, 43% and 9% for conventionally produced cereals and 40%, 63%, 30%, 41%, and 18% for organically produced cereals, respectively. The mean levels of DON, NIV, 3ADON, 15ADON and FUS-X in the toxin-positive samples were, respectively, 46.7, 23.3, 4.1, 6.6 and 10.7 μg/kg for conventionally produced cereals and 59.3, 32.4, 4.1, 9.9 and 7.3 μg/kg for organically produced cereals. No significant differences in DON, 3ADON, 15ADON and FUS-X concentrations were found between conventionally produced and organically produced cereals. However, the levels of NIV in organically produced rice and brown rice were significantly higher than those in the corresponding conventional samples. These data indicate that the contamination of cereals with 8-ketotrichothecenes may vary greatly according to the type of cereals grown as well as to the production method, such as organic farming.