Abstract

Veterinary pharmaceuticals (VPs) are routinely used in livestock breeding. As a consequence, high concentrations of such VPs can be found in liquid manure, which is often applied to arable crops and grassland. From the soil, the VPs may enter surface water bodies via edge-of-field runoff, representing a potential risk to aquatic ecosystems. In the present study, the worst-case runoff predictions obtained by the FOCUS step 3 modeling approach, which is recommended for environmental-risk assessment of VPs in Europe, were compared with fate data obtained from experimental plot studies involving both arable and grassland plots. Five VPs were selected comprising three sulfonamides (sulfadiazine, sulfadimidine, sulfamethoxazole) and two benzimidazoles (fiubendazole, fenbendazole). The respective concentrations in runoff were initially estimated using literature data for model parameterization. Subsequently, the scenarios were parameterized specifically for each experimental plot study performed, enabling a direct comparison of the model performance with the close-to-field relevant situation.Generally, substantial variations between the predicted and measured concentrations of VPs in the runoff were uncovered. Although the FOCUS prediction suggested higher concentrations than were actually measured in 65% of the cases, the runoff concentrations of VPs were underestimated in the remaining 35%. This frequent underestimation of runoff concentrations was primarily observed for the grassland plots (85% of the underestimated situations), whereas the FOCUS predictions largely overestimated the measured concentrations for the arable plots. More strikingly, when involving a difference between the measured and predicted concentrations of 10% as a validity criterion for the model, only one (out of a total of 17) runoff concentration among the five VPs (i.e., sulfadimidine) assessed in the seven scenarios fell within this tolerance margin. Thus, these results demonstrate the substantial uncertainties related to the use of the FOCUS surface water modeling approach for the prediction of VPs introduced with manure and their environmental risk. (C) 2015 Elsevier B.V. All rights reserved.

Keywords

Veterinary pharmaceuticals; FOCUS model; Sulfonamide antibiotics; Benzimidazole anthelmintics; Exposure modeling

Published in

Agriculture, Ecosystems and Environment
2016, Volume: 218, pages: 33-39
Publisher: ELSEVIER SCIENCE BV

SLU Authors

• Bundschuh, Mirco

  • Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences
    
  • University of Koblenz-Landau

UKÄ Subject classification

Other Natural Sciences not elsewhere specified


Publication identifier

DOI: https://doi.org/10.1016/j.agee.2015.10.022

Permanent link to this page (URI)

https://res.slu.se/id/publ/80863