Input of antibiotics into the aquatic environment
Subproject 5: Development, optimization and validation of methods for the determination of antibiotics in waste water
Abstract
The aim of this research project is to investigate the degradability of 18 selected antibiotics of different chemical compound classes by use of biodegradability tests and by sampling and analysis of real waste water samples. In different sets of experiments closed-bottle tests, an anaerobic degradation test, the modified Sturm test and a degradation test based on a lab-scale waste water treatment model are carried out. Since these tests may suffer from artefacts due to the biozide properties of the tested antibiotics, these experiments have also to be carried out at low concentrations, i.e. in the µg/L range. Therefore, in the subproject of TZW, methods of analysis for the determination of antibiotics in waste water are developed, optimized, and validated. For this purpose, liquid chromatography-electrospray-tandem mass spectrometry (LC-ESI-MS-MS) is applied, because most of the antibiotics under investigation cannot be analyzed by conventional methods like HPLC-UV or GC-MS. The methods developed are used to analyze samples from the biodegradation tests and also from municipal waste water treatment plants. The results of the analyses of waste water samples confirm the results of the degradation tests and fit to expectations derived from a local mass balance on the basis of the applied antibiotic volumes. The antibiotics found during analysis of numerous surface water samples (e.g. macrolide antibiotics and some chemotherapeutics like trimethoprim or sulfamethoxazole) are identical with those compounds which are not completely eliminated in the waste water treatment plant.
Abstract
The aim of this research project is to investigate the degradability of 18 selected antibiotics of different chemical compound classes by use of biodegradability tests and by sampling and analysis of real waste water samples. In different sets of experiments closed-bottle tests, an anaerobic degradation test, the modified Sturm test and a degradation test based on a lab-scale waste water treatment model are carried out. Since these tests may suffer from artefacts due to the biozide properties of the tested antibiotics, these experiments have also to be carried out at low concentrations, i.e. in the µg/L range. Therefore, in the subproject of TZW, methods of analysis for the determination of antibiotics in waste water are developed, optimized, and validated. For this purpose, liquid chromatography-electrospray-tandem mass spectrometry (LC-ESI-MS-MS) is applied, because most of the antibiotics under investigation cannot be analyzed by conventional methods like HPLC-UV or GC-MS. The methods developed are used to analyze samples from the biodegradation tests and also from municipal waste water treatment plants. The results of the analyses of waste water samples confirm the results of the degradation tests and fit to expectations derived from a local mass balance on the basis of the applied antibiotic volumes. The antibiotics found during analysis of numerous surface water samples (e.g. macrolide antibiotics and some chemotherapeutics like trimethoprim or sulfamethoxazole) are identical with those compounds which are not completely eliminated in the waste water treatment plant.
Funding
Federal Environmental Agency (UBA), FKZ: 298 63 722
