A5032783068- Toxic Organic Pollutants Impact
- Microbial bioremediation and biosurfactants
- Isotope Analysis in Ecology
- Water Treatment and Disinfection
- Pharmaceutical and Antibiotic Environmental Impacts
- Radioactive element chemistry and processing
- Chemical Reactions and Isotopes
- Analytical chemistry methods development
- Microbial Community Ecology and Physiology
- Groundwater and Isotope Geochemistry
- Radioactive contamination and transfer
- Mass Spectrometry Techniques and Applications
- Chemical Analysis and Environmental Impact
- Soil and Water Nutrient Dynamics
- Biosensors and Analytical Detection
- Methane Hydrates and Related Phenomena
- Atmospheric chemistry and aerosols
- CO2 Sequestration and Geologic Interactions
- Pesticide and Herbicide Environmental Studies
- Hydrocarbon exploration and reservoir analysis
- Anaerobic Digestion and Biogas Production
- Soil erosion and sediment transport
- Atmospheric and Environmental Gas Dynamics
- Effects and risks of endocrine disrupting chemicals
- Hydrology and Watershed Management Studies
Helmholtz Centre for Environmental Research
2016-2025
University of Freiburg
2013-2016
Sulfonamides are applied worldwide as antibiotics. They emerging contaminants of concern, their presence in the environment may lead to spread antibiotic resistance genes. present groundwater systems, which suggest persistence under certain conditions, highlighting importance understanding natural attenuation processes groundwater. Biodegradation is an essential process, degradation sulfonamides reduces risk spreading. In this review, attenuation, and particular assessment biodegradation,...
Polycyclic aromatic hydrocarbons (PAH) are widespread and persistent environmental contaminants, especially in oxygen-free environments. The occurrence of anaerobic PAH-degrading bacteria their underlying metabolic pathways rarely known. In this study, PAH degraders were enriched laboratory microcosms under sulfate-reducing conditions using groundwater sediment samples from four PAH-contaminated aquifers. Five enrichment cultures obtained showing sulfate-dependent naphthalene degradation....
Abstract Recent discovery of methane (CH 4 ) production in oxic waters challenges the conventional understanding strict anoxic requirement for biological CH production. High‐resolution field measurements Lake Stechlin, as well incubation experiments, suggested that oxic‐water occurred throughout much water column and was associated with phytoplankton especially diatoms, cyanobacteria, green algae, cryptophytes. In situ concentrations δ 13 C values were negatively correlated soluble reactive...
Sulfamethoxazole (SMX) is a frequently detected antibiotic in groundwater, raising environmental concerns. Persulfate oxidation used for micropollutant removal. To investigate SMX transformation by persulfate, experiments were conducted using heat-activated persulfate at pH 3, 7, and 10. TP269a (SMX-hydroxylamine) TP178 identified as the dominant TPs across levels. The exclusive formation of 4-nitroso-SMX, 4-nitro-SMX, TP518 3 highlighted role SO4•- attacking NH2. At 7 10, 3A5MI emerged TP....
The traditional high-temperature conversion (HTC) approach toward compound-specific stable isotope analysis (CSIA) of hydrogen for heteroatom-bearing (i.e., N, Cl, S) compounds has been afflicted by fractionation bias due to formation byproducts HCN, HCl, and H2S. This study presents a chromium-based (Cr/HTC) organic containing nitrogen, chlorine, sulfur. Following peak separation along gas chromatographic (GC) column, the use thermally ceramic Cr/HTC reactors at 1100-1500 °C chemical...
Methanol is generally metabolized through a pathway initiated by cobalamine-containing methanol methyltransferase anaerobic methylotrophs (such as methanogens and acetogens), or oxidation to formaldehyde using dehydrogenase aerobes. an important substrate in deep-subsurface environments, where thermophilic sulfate-reducing bacteria of the genus Desulfotomaculum have key roles. Here, we study metabolism kuznetsovii strain 17T, isolated from 3000-m deep geothermal water reservoir. We use...
Multi-element compound-specific stable isotope analysis (ME-CSIA) allows monitoring the environmental behavior and transformation of most common persistent contaminants. Recent advancements in analytical techniques have extended applicability ME-CSIA to organic micropollutants, including pesticides. Nevertheless, application this methodology remains unexplored concerning harmful insecticides such as methoxychlor, a polar organochlorine pesticide usually detected soil groundwater. This study...
The antibiotic sulfamethoxazole (SMX) undergoes direct phototransformation by sunlight, constituting a notable dissipation process in the environment. SMX exists both neutral and anionic forms, depending on pH conditions. To discern photodegradation of at various levels differentiate it from other transformation processes, we conducted under simulated sunlight 7 3, employing product (TP) compound-specific stable isotope analyses. At 7, primary TPs were sulfanilic acid 3A5MI, followed...
Abstract Trichodesmium is an important dinitrogen (N2)-fixing cyanobacterium in marine ecosystems. Recent nucleic acid analyses indicate that colonies with their diverse epibionts support various nitrogen (N) transformations beyond N2 fixation. However, rates of these and concentration gradients N compounds remain largely unresolved. We combined isotope-tracer incubations, micro-profiling numeric modelling to explore carbon fixation, cycling processes as well oxygen, ammonium nitrate...
High temperature-aquifer thermal energy storage (HT-ATES) aims at the seasonal and extraction of large quantities heat in subsurface. However, impacts temperature fluctuations caused by HT-ATES toward biodiversity ecosystem services subsurface environment with respect to nitrogen cycle remain unclear. Hence, understanding possible adaptation mechanisms aquifer microbial communities is crucial assess potential environmental risks associated HT-ATES. In this study, we investigated effects...
The widespread occurrence of micropollutants like the antibiotic sulfadimidine in environment has become a growing concern. Compound-specific stable isotope analysis (CSIA) offers powerful tool for tracking fate such pollutants, but its application is often limited by low sensitivity. To address this limitation, large-scale solid-phase extraction method was developed to extract, enrich, and isolate δ13C- δ34S-CSIA. Each step carefully evaluated, ensuring no detectable artifacts. limit...
ATES (Aquifer Thermal Energy Storage) is a CO2-free technology for seasonal heating or cooling of buildings based on the storage and recovery thermal energy in aquifer. Since aquifers urban areas are often contaminated with organic pollutants, application raises research question whether this type heat management can accelerate natural attenuation processes. In KONATES project, we investigating how warm water (70°C) an aquifer trichloroethene (TCE) impacts aquifer’s...
Climate change, marked by rising atmospheric CO₂ levels and temperature, can strongly influence soil processes such as nutrient cycling microbial dynamics. Metals negatively impact functionality, modify community composition activity, introducing additional complexity to under shifting environmental conditions. In addition, metals disrupt plant growth uptake, affect root development trigger stress responses, ultimately compromising productivity. On the other hand, elevated...
Soil cadmium (Cd) contamination is a widespread problem in Europe, disrupting plant growth, impairing microbial activity, and threatening human health. Phytoextraction using metal hyperaccumulating plants, like Arabidopsis halleri, offers sustainable approach to mitigate Cd pollution soils. However, the supply of essential nutrients for growth hyperaccumulation crucial an efficient application phytoremediation. Nitrogen (N), key nutrient undergoing diverse microbially driven transformations...
ABSTRACT The participants of the 12 th International Atomic Energy Agency (IAEA) meeting on stable isotope reference materials reached a consensus, acknowledging existence and use two carbon delta scales: VPDB (Vienna Peedee belemnite) scale VPDB‐LSVEC (LSVEC ‐ lithium carbonate prepared by H. J. Svec). Conversion models between scales can be established used but introduce uncertainty. A format for definition was agreed upon to define main oxygen scales, VSMOW‐SLAP Standard Mean Ocean...
Accurate hydrogen isotopic analysis of halogen- and sulfur-bearing organics has not been possible with traditional high-temperature conversion (HTC) because the formation hydrogen-bearing reaction products other than molecular (H2 ) is responsible for non-quantitative H2 yields fractionation. Our previously introduced, new chromium-based EA-Cr/HTC-IRMS (Elemental Analyzer-Chromium/High-Temperature Conversion Isotope Ratio Mass Spectrometry) technique focused primarily on nitrogen-bearing...