Submitted to: Environmental Science and Technology
Publication Type: Peer reviewed journal
Publication Acceptance Date: 3/19/2003
Publication Date: 4/25/2003
Citation: Casey, F.X., Larsen, G.L., Hakk, H., Simunek, J. 2003. Fate and transport of 17beta-estradiol in soil - water systems. Environmental Science and Technology. 37:2400-2409. Interpretive Summary: Over the past several years, there has been an increase in concern regarding reproductive hormones in the environment. To date, there exists limited research on the fate and transport of these chemicals in the environment. In this study, a series of laboratory soil/hormone interaction and soil column experiments were conducted using the female hormone estradiol. Estradiol concentrations that were used were similar to those found in manures that were applied to field soils. In the soil/estradiol interaction experiments it was shown that the absorption of the hormone to the soil was effected by the soil particle size, amount of soil organic matter, the soil surface area, and the quantity positively charged particles in the soil. The soil appeared to break down the estradiol to a single water soluble product called estriol which was present in the soil and the water solution coming through the soil column. Models were used to describe the movement and interaction of the hormone with the soil as the hormone moved through the soil column. The modeling and experimental results implied that estradiol degradation occurred rapidly as it interacted with the soil.
Technical Abstract: Over the past several years, there has been an increase in concern regarding reproductive hormones in the environment. To date, there exists limited research on the fate and transport of these chemicals in the environment. In this study, a series of laboratory batch sorption and miscible-displacement experiments were done using radiolabeled 17beta-estradiol. The 17beta-estradiol concentrations that were used were similar to those found in manures that were applied to field soils. Equilibrium batch experiments indicated high sorption affinity correlations to mineral particle size and organic matter content. The sorption affinity appeared to be associated with the surface area and/or the cation-exchange capacity of the soil. The miscible-displacement breakthrough curves indicated chemical nonequilibrium transport, and a single highly polar metabolite was present in the column effluent along with sporadic and trace detections of estriol. Sorbed to the soil within the column were found E, estrone, and trace and sporadic detections of estriol. Two chemical nonequilibrium, miscible-displacement models were used to describe the column breakthrough curves; one without transformations and the other with transformations. Both models resulted in excellent descriptions of the data, which indicated nonunique solutions and less confidence in the parameter estimates. Nonetheless, the modeling and experimental results implied that degradation/transformation occurred in the sorbed phase and was rapid. Also both models indicated that sorption was fully kinetic.most mineralization occurred on the sorbed phase and that sorption was fully kinetic.