Leaching and binding of fumonisins in soil microcosms.

Fumonisin B(1) (FB(1)) is a water-soluble mycotoxin produced by Fusarium verticillioides. Our research objectives were to determine the leaching of FB(1) through soils and FB(1) binding in soil. Leachate columns were used to determine the movement of FB(1) through soil. FB(1)-contaminated corn screenings or water extracts containing FB(1) were placed on the surface of soil columns. In 100% sand columns, FB(1) leaching was only slightly retarded, whereas at 50%, 75%, and 100% Cecil sandy loam, approximately 60%, 50%, and 20% of the FB(1) was recovered in the column leachate, respectively. The FB(1) retained on the 100% Cecil sandy loam column was tightly bound. However, approximately 75% of the bound FB(1) was released with 5% formic acid and 5% formic acid/acetonitrile (1:1), indicating that the nature of the interaction was probably ionic. The results suggest that FB(1) is quite stable in soils and, while tightly bound, under certain environmental conditions could be released.