Sorption of sulfisoxazole onto soil—an insight into different influencing factors

Abstract

Although sulfonamides (SAs) are among the most commonly used veterinary drugs and their presence in the environment is well documented, knowledge of their fate and behavior in the soil environment is still limited, especially for sulfisoxazole (SSX) which is characterized by the lowest (among other SAs) pK a value associated with acid-base equilibrium of sulfonamide group. Thus, this work was focused on determining the sorption potential of SSX onto natural soils differing in physicochemical properties. All the results were modeled using linear, Freundlich, Langmuir, Dubinin-Radushkevich, and Temkin sorption isotherms. The established sorption coefficients (K(d)) for SSX were quite low (from 0.27 to 0.95 L kg(-1)), which indicated that this substance is highly mobile and has the potential to run off into surface waters and/or infiltrate ground water. The sorption data of SSX is well fitted to the Freundlich isotherm model (R(2) > 0.968). Moreover, we assessed the sorption mechanism of these compounds in the edaphic environment with respect to organic matter (OM) content, pH, and ionic strength. To clarify the current state of knowledge, these factors were examined much more thoroughly than in previous investigations concerning other SAs. The wide range of ionic strength examined showed positive correlation of this factor and sorption of SAs. The results also yielded new insight into dependency of sorption of SAs on organic matter content in soil.

Effect of Soil Solution Properties and Cu2+ Co-Existence on the Adsorption of Sulfadiazine onto Paddy Soil

“…With increased detection of heavy metals and antibiotics in soils, more attention has been paid to the process of antibiotics related to the co-existent metal ions, aside from the various soil properties [33][34][35]. It is widely thought that heavy metal cations may influence the mobility of antibiotics in soils, through ion exchange or complexation.…”