Abstract # A-06

A liquid chromatographic method for determination of deoxynivalenol (DON) in processed wheat products at 1 µg/g was developed. The method was used in a survey study and evaluated by a mini collaborative study. Test samples were extracted by blending with acetonitrile-water (84 + 16), filtered and passed through a solid phase extraction column. The eluate was separated on a reversed-phase LC column by using a gradient of water and methanol. DON was measured by absorbance at 220 nm. Of the 562 wheat-based products analyzed from the 1993 crop year, 64 (11%) contained DON levels above the 1 µg/g FDA advisory level. In the collaborative study, naturally contaminated white flour, whole wheat flour, and bran; and spiking solutions of DON to be added to the 3 commodities at 0.5, 1.0 and 2.0 µg/g, were sent to 3 collaborators. Three collaborators completed the study. Average recoveries of DON for each spike level for the 3 commodities were 94, 87 and 97% respectively; the repeatability relative standard deviation (RSDr) ranged from 3.1 to 21.7% and the reproducibility relative standard deviation (RSDR) ranged from 10.8 to 38.7%. The results of this study are comparable to those of AOAC officical methods for DON and will be submitted to AOAC for consideration as a peer verified method.