Bound residues in corn plants treated with 14C-atrazine and bioavailability to rats

Corn plants, about 3.5 months old and treated with 14C-atrazine, were used in an experiment in which the aerial portion of the plants was exhaustively extracted with solvents. The extracted dried material containing bound 14C-residues was fed to rats. The extracted aerial portion of control corn plants fortified with 14C-atrazine was also fed to rats. After four days, 88% and 32% of the radioactivity was excreted in the faeces, and 10% and 60% radioactivity was voided in the urine from rats fed plant material containing bound and fortified 14C-residues, respectively. The data suggest that the bioavailability to rats of bound 14C-residues in corn material is low. (author)