Suchergebnisse

This report addresses the role of antibiotic residues for the development or dissemination of antibiotic resistance in environmental compartments. A literature study summarizes data on fate and occurrence of antibiotics in the environment. Next, an overview of the existing information on effects of antibiotics at environmentally-relevant concentrations is provided. It is concluded that there is too limited information to judge whether antibiotic residues in the environment can exert effects on resistance, but that such effects cannot be ruled out, when extrapolating from collections of minimum inhibitory concentrations (MIC) and from data on minimum selective concentrations. A range of test methods for the detection of antibiotic resistance are described and evaluated with respect to their suitability as regulatory test systems. A combination of culture-based and molecular methods appears most promising, in combination with tests for resistance gene transfer. The methods generally lack standardisation. An inclusion of the effects of environmental antibiotic residues on resistance in the environmental risk assessment procedures of human and veterinary antibiotics is discussed. Given that manure and sewage effluent can be relevant hotspots and sources of resistant bacteria in the environment and that other chemicals such as heavy metals can also increase resistance, surveillance of environmental resistance is also recommended. Finally, a possible test system is described, research needs are identified, and the results of an international expert meeting are summarized.