The experiment was carried out under laboratory conditions in order to know the remobilization of 14C-atrazine bound residues in two soils from São Paulo State. Hapludox and Umbraquults soils were incubated for 49 days with 14C-atrazine in special flasks. The 14CO2 evolution was measured according to COSTA (1992). The extraction by solvent and organic matter fractionation were made following LAVORENTI et al. (1997). The extracts obtained were analyzed for their radioactivity and RF values of TLC. The atrazine mineralization from the Umbraquults soil was of minor importance for its detoxification. The hidroxiatrazine was the main metabolite of the atrazine found in both soils. The greatest percentage of atrazine bound residues was found in the humine and fulvic acid fractions, followed by humic acids.
atrazine; remobilization; fulvic acids; bound residues