Survey for zearalenone, aflatoxin, and ochratoxin in U.S. grain sorghum from 1975 and 1976 crops

Grain sorghum samples (197) from 10 [USA] states harvested in 1975 and 1976 were analyzed for zearalenone, aflatoxin and ochratoxin by the Eppley procedure. Zearalenone was detected in 56 samples (28%) at levels of 200-6900 ng/g (the detection limit was 100-200 ng/g). Zearalenone identity was confirmed in representative samples by gas chromatography-mass spectroscopy of the trimethylsilyl derivatives. No ochratoxin was detected in any sample (the detection limit was about 50 ng/g). Aflatoxin was detected in 4 samples at levels of 54, 6, 10 and 7 ng total aflatoxin g (the detection limit was approximately 3 ng/g). The identity of aflatoxin B1 in the samples was confirmed by formation of the water adduct on TLC plates.