Compartment-specific effect of sulfamethoxazole at low μg/L concentrations on microbial nitrogen assimilation in a river system

Sulfamethoxazole (SMX) is one of the most frequently detected antibiotics in rivers, with concentrations occasionally exceeding the predicted no-effect concentration (PNEC). The impact of such concentrations on the microbial activity of riverine microbial communities remains poorly studied. Here, we...

Full description

Saved in:
Bibliographic Details
Main Authors: Sarah Haenelt, Caglar Akay, Hans-Hermann Richnow, Steffen Kümmel, Hryhoriy Stryhanyuk, Jochen A. Müller, Niculina Musat
Format: Article
Language:English
Published: Elsevier 2025-09-01
Series:Water Research X
Subjects:
Online Access:http://www.sciencedirect.com/science/article/pii/S2589914725000891
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849240486659751936
author Sarah Haenelt
Caglar Akay
Hans-Hermann Richnow
Steffen Kümmel
Hryhoriy Stryhanyuk
Jochen A. Müller
Niculina Musat
author_facet Sarah Haenelt
Caglar Akay
Hans-Hermann Richnow
Steffen Kümmel
Hryhoriy Stryhanyuk
Jochen A. Müller
Niculina Musat
author_sort Sarah Haenelt
collection DOAJ
description Sulfamethoxazole (SMX) is one of the most frequently detected antibiotics in rivers, with concentrations occasionally exceeding the predicted no-effect concentration (PNEC). The impact of such concentrations on the microbial activity of riverine microbial communities remains poorly studied. Here, we investigated the effect of SMX concentrations at the upper end of reported PNEC values (12.5 µg/L) on microbial communities in flume systems with either near-pristine or wastewater-impacted river water. Using a combination of microbiological and chemical methods, we found that SMX was persistent in both near-pristine and wastewater-impacted river water over a time course of 63 days, and had no significant impact on the planktonic bacterial community composition. However, there was an increase in microbial activity after SMX addition. Tracking 15N incorporation in the samples using Nanoscale Secondary Ion Mass Spectrometry (NanoSIMS) and an Elemental Analyser - Isotope Ratio Mass Spectrometer (EA-IRMS) revealed that SMX concentrations in the test range (10, 100 and 1000 µg/L) enhanced nitrogen assimilation from ammonium up to 64 %. The highest increase was found almost always at 10 µg/L SMX. The response was stronger in samples from the near-pristine site compared to the wastewater-impacted site, and in planktonic biomass compared to biofilms. Overall, our findings reveal a transient increase in microbial nitrogen assimilation with environmentally relevant concentrations of SMX in a habitat-specific manner, but not of SMX degradation, which could be of significance for nutrient dynamics and primary productivity in impacted rivers.
format Article
id doaj-art-effef5d0b8ea4e5cbca03f6e0f4a631f
institution Kabale University
issn 2589-9147
language English
publishDate 2025-09-01
publisher Elsevier
record_format Article
series Water Research X
spelling doaj-art-effef5d0b8ea4e5cbca03f6e0f4a631f2025-08-20T04:00:34ZengElsevierWater Research X2589-91472025-09-012810039010.1016/j.wroa.2025.100390Compartment-specific effect of sulfamethoxazole at low μg/L concentrations on microbial nitrogen assimilation in a river systemSarah Haenelt0Caglar Akay1Hans-Hermann Richnow2Steffen Kümmel3Hryhoriy Stryhanyuk4Jochen A. Müller5Niculina Musat6Department of Technical Biogeochemistry, Helmholtz Centre for Environmental Research, Leipzig, GermanyDepartment of Molecular Environmental Biotechnology, Helmholtz Centre for Environmental Research, Leipzig, Germany; Department of Exposure Science, Helmholtz Centre for Environmental Research, Leipzig, GermanyDepartment of Technical Biogeochemistry, Helmholtz Centre for Environmental Research, Leipzig, GermanyDepartment of Technical Biogeochemistry, Helmholtz Centre for Environmental Research, Leipzig, GermanyDepartment of Technical Biogeochemistry, Helmholtz Centre for Environmental Research, Leipzig, GermanyInstitute for Biological Interfaces (IBG 5), Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Karlsruhe, Germany; Correspondence authors.Department of Technical Biogeochemistry, Helmholtz Centre for Environmental Research, Leipzig, Germany; Department of Biology, Section for Microbiology, Aarhus University, Aarhus, Denmark; Correspondence authors.Sulfamethoxazole (SMX) is one of the most frequently detected antibiotics in rivers, with concentrations occasionally exceeding the predicted no-effect concentration (PNEC). The impact of such concentrations on the microbial activity of riverine microbial communities remains poorly studied. Here, we investigated the effect of SMX concentrations at the upper end of reported PNEC values (12.5 µg/L) on microbial communities in flume systems with either near-pristine or wastewater-impacted river water. Using a combination of microbiological and chemical methods, we found that SMX was persistent in both near-pristine and wastewater-impacted river water over a time course of 63 days, and had no significant impact on the planktonic bacterial community composition. However, there was an increase in microbial activity after SMX addition. Tracking 15N incorporation in the samples using Nanoscale Secondary Ion Mass Spectrometry (NanoSIMS) and an Elemental Analyser - Isotope Ratio Mass Spectrometer (EA-IRMS) revealed that SMX concentrations in the test range (10, 100 and 1000 µg/L) enhanced nitrogen assimilation from ammonium up to 64 %. The highest increase was found almost always at 10 µg/L SMX. The response was stronger in samples from the near-pristine site compared to the wastewater-impacted site, and in planktonic biomass compared to biofilms. Overall, our findings reveal a transient increase in microbial nitrogen assimilation with environmentally relevant concentrations of SMX in a habitat-specific manner, but not of SMX degradation, which could be of significance for nutrient dynamics and primary productivity in impacted rivers.http://www.sciencedirect.com/science/article/pii/S2589914725000891Riverine microbial communityFlume systemAntimicrobialsPNECMicrobial activityNanoSIMS
spellingShingle Sarah Haenelt
Caglar Akay
Hans-Hermann Richnow
Steffen Kümmel
Hryhoriy Stryhanyuk
Jochen A. Müller
Niculina Musat
Compartment-specific effect of sulfamethoxazole at low μg/L concentrations on microbial nitrogen assimilation in a river system
Water Research X
Riverine microbial community
Flume system
Antimicrobials
PNEC
Microbial activity
NanoSIMS
title Compartment-specific effect of sulfamethoxazole at low μg/L concentrations on microbial nitrogen assimilation in a river system
title_full Compartment-specific effect of sulfamethoxazole at low μg/L concentrations on microbial nitrogen assimilation in a river system
title_fullStr Compartment-specific effect of sulfamethoxazole at low μg/L concentrations on microbial nitrogen assimilation in a river system
title_full_unstemmed Compartment-specific effect of sulfamethoxazole at low μg/L concentrations on microbial nitrogen assimilation in a river system
title_short Compartment-specific effect of sulfamethoxazole at low μg/L concentrations on microbial nitrogen assimilation in a river system
title_sort compartment specific effect of sulfamethoxazole at low μg l concentrations on microbial nitrogen assimilation in a river system
topic Riverine microbial community
Flume system
Antimicrobials
PNEC
Microbial activity
NanoSIMS
url http://www.sciencedirect.com/science/article/pii/S2589914725000891
work_keys_str_mv AT sarahhaenelt compartmentspecificeffectofsulfamethoxazoleatlowmglconcentrationsonmicrobialnitrogenassimilationinariversystem
AT caglarakay compartmentspecificeffectofsulfamethoxazoleatlowmglconcentrationsonmicrobialnitrogenassimilationinariversystem
AT hanshermannrichnow compartmentspecificeffectofsulfamethoxazoleatlowmglconcentrationsonmicrobialnitrogenassimilationinariversystem
AT steffenkummel compartmentspecificeffectofsulfamethoxazoleatlowmglconcentrationsonmicrobialnitrogenassimilationinariversystem
AT hryhoriystryhanyuk compartmentspecificeffectofsulfamethoxazoleatlowmglconcentrationsonmicrobialnitrogenassimilationinariversystem
AT jochenamuller compartmentspecificeffectofsulfamethoxazoleatlowmglconcentrationsonmicrobialnitrogenassimilationinariversystem
AT niculinamusat compartmentspecificeffectofsulfamethoxazoleatlowmglconcentrationsonmicrobialnitrogenassimilationinariversystem