Submitted to: Toxicologist
Publication Type: Abstract Only
Publication Acceptance Date: 11/1/2002
Publication Date: 3/1/2002
Citation: Williams, L.D., Bacon, C.W., Showker, A.J., Meredith, F.I., Franzluebbers, A.J., Smith, M.A., Wyatt, R., Riley, R.T. 2002. KINETICS AND BINDING OF FUMONISIN IN A MODEL SOIL SYSTEM. Toxicologist. 66:69-70.
Interpretive Summary: Abstract only.
Technical Abstract: Fumonisin B1 (FB1) is a water soluble, carcinogenic mycotoxin produced by the fungus Fusarium moniliforme, which is parasitic to corn plants. It can be found in the ear, roots, and stalks of plants. It is estimated that 90% of the FB1 consumed by livestock is excreted unmetabolized. The objectives of this research are to determine 1) the kinetics of FB1 interaction with soil constituents, and 2) if FB1 is chemically modified in the soil. Leachate columns were used to determine the movement of FB1 through soil matrices comprised of washed sand and 0%, 50%, 75%, or 100% Cecil sandy loam soil. The movement of FB1 was compared to that of bromophenol blue (Bb), a dye that moved freely through the soil columns. FB1-contaminated corn screenings or extracts containing FB1 were placed on the surface of the soil columns. When corn screenings were used as the source of FB1, a rain simulator was attached to the top of the column and water was allowed to saturate the corn screenings (extracting the FB1) and percolate through the column eluting the FB1. The 100% sand columns slightly retarded the efflux of FB1 relative to Bb but did not appear to chemically alter the FB1. The recovery of FB1 decreased with increasing concentrations of Cecil sandy loam soil. At 0%, 50%, 75% and 100% Cecil sandy loam, approximately 80%, 60%, 50% and 20% of the FB1 was recovered in the column leachate, respectively. The FB1 retained in the 100% Cecil sandy loam column was tightly bound as evidenced by the fact it could not be extracted using acetonitrile:water (1:1). However, approximately 40% of the retained FB1 was extractable using 5% formic acid:acetonitrile (1:1) indicating that the nature of the interaction was probably ionic. The result of this study indicate that FB1 is probably stable in the soil environment and suggests that while some is tightly bound, under certain environmental conditions FB1 could be released, become biologically available and possibly contaminate the water supply.