Synergistic and Competitive Sorption of Androgens and Glucocorticoids in Freshwater Sediment.

Androgens and glucocorticoids are prevalent in the environment, posing significant risks to human and ecological health. However, their sorption behaviors in sediments remain poorly understood. This study investigated the sorption characteristics of two androgens and two glucocorticoids, both individually and in binary mixtures, in freshwater sediment. The results showed that the sorption of these four steroids aligned more closely with pseudo-second-order kinetics. Higher initial concentrations resulted in larger equilibrium sorption capacities and smaller sorption rate constants except DEX. The sorption isotherms were better described by the Langmuir model, with androgens exhibiting smaller adsorption capacities compared to glucocorticoids, ranging from a minimum of 70.04 mg/kg for androstenedione to a maximum of 322.3 mg/kg for cortisone. In binary adsorbate systems, the coexistence of androstenedione and methyltestosterone exhibited synergistic sorption, as did the coexistence of androstenedione and dexamethasone. Dexamethasone competed with either cortisone or methyltestosterone when they coexisted. This study enhances the understanding of the environmental fate of steroid hormone and provides theoretical support for accurately assessing their ecological risks. [ABSTRACT FROM AUTHOR]