Mapping the Environmental Risk of Antibiotic Contamination by Using Multi-Criteria Decision Analysis

Veterinary antibiotics have widely been used for promoting animal health, especially in the last few decades. As a result of application of manure on agricultural lands, leaching of antibiotics from manure to soil and antibiotic transport via runoff may cause both soil and water quality degradation. Moreover, an increased antibiotic concentration in soil stimulates the development of antibiotic resistant bacteria in the environment. The aim of this study was to develop environmental risk maps for the Marmara Region by taking into account the antibiotic transport from the pasture lands. By using geographical information systems, the region was divided into manageable modelling units according to different topographical and hydrodynamic characteristics. A storm water management model was applied for runoff prediction. The transport of previously analyzed antibiotics in the region was determined by using an exposure model developed by the National Institute of Public Health and the Environment, the Netherlands. The environmental risk of antibiotics was mapped by undertaking a multi-criteria decision analysis approach for all pasture lands. The risk maps showed that the potential risk of antibiotic transport from pasture lands is moderate across the Marmara Region, however, a high level of risk prevailed in some areas, particularly in Balikesir.