Biotic and abiotic degradation of S-metolachlor and its commercial product Mercantor Gold® in aqueous media

Aktivität: Vorträge und GastvorlesungenPräsentationen (Poster ua.)Forschung

Lukasz Gutowski - Sprecher*in

Oliver Olsson - Ko-Autor*in

Klaus Kümmerer - Ko-Autor*in

Lukasz Gutowski - Präsentator*in

S-metolachlor (2-chloro-N-(2-ethyl-6-methylphenyl)-N-[(1S)-2-methoxy-1-methylethyl] acetamide) is a selective chloroacetanilide herbicide intensively used for annual grassy weeds, corn, soybeans, peanuts, and other crops. In recent years more effective and risk-reduced S enantiomer has replaced the existing rac-metolachlor in the worldwide market since 1976. Mercantor Gold® is a mixture of S-metolachlor (86%) with mixture of aromatic hydrocarbons (14%). Once the compound is released into the environment it undergoes both biotic and non-biotic processes. As large amounts of pesticide are introduced to the environment, it is of great importance to investigate the biodegradation and photodegradation in the natural environment.
The present study investigates the environmental pathways of S-Metolachlor and its commercial product Mercantor Gold® by Syngenta. Two tests of different bacterial density from OECD series were applied to test the biodegradation: the Closed Bottle Test (CBT, OECD 301D) and Manometric Respiratory Test (MRT, OECD 301 F). Photodegradation in aqueous media under simulated solar irradiation was performed using a UV/VIS xenon lamp (TXE 150, UV consulting Peschl, Mainz), which emits spectra similar to natural sun light (300-800nm). Samples after 8h photodegradation were administered the CBT and MRT biodegradation tests. The primary elimination of parent compound was monitored at 220 nm by high performance liquid chromatography (HPLC-UV). The formed transformation products (TP’s) were analyzed by liquid chromatography coupled with multiple stage ion trap mass-spectrometry (LC-Ms).
S-metolachlor was efficiently photo-degraded under laboratory conditions. Analyses by HPLC-UV showed a 69% elimination of pure compound and a 74% elimination of commercial product, both dissolved in water. Abundant photoproducts were detected by LC-Ms. No biodegradation has been observed for two compounds in the CBT and MRT tests as well as in the samples after photo-treatment. However, analyses through the MRT test revealed new TP’s in the samples after photodegradation.
This study obtained results which show that S-metolachlor as well as its commercial product Mercantor Gold® efficiently undergo abiotic primary elimination in aqueous media, however their photo-TP’s are not biodegradable in performed tests and therefore might be persistent in the environment or exhibit further transformations.
17.11.201321.11.2013

Veranstaltung

34th Annual Meeting of the Society of Environmental Toxicology and Chemistry North America- SETAC 2013

17.11.1321.11.13

Nashille, USA / Vereinigte Staaten

Veranstaltung: Konferenz

    Fachgebiete

  • Chemie - photodegradation, transformation product

Zuletzt angesehen

Forschende

  1. Norbert Feldhoff

Publikationen

  1. Constructing small talk in learner-native speaker voice-based telecollaboration
  2. What do we do with "other" music?
  3. A call for statistical editors in ecology
  4. Testing for Economies of Scope in European Railways
  5. Sustainability learnings from the COVID-19 crisis
  6. Effect of Welding Speed on Friction Stir Welds of PM2000 Alloy
  7. Acquiring 'different strokes'.
  8. People Information in Provenance Data
  9. Observations of Microstructure-Oriented Crack Growth in a Cast Mg-Al-Ba-Ca Alloy under Tension, Compression and Fatigue
  10. Challenges and opportunities in linking carbon sequestration, livelihoods and ecosystem service provision in drylands
  11. Joint production, externalities, and the regulation of production networks
  12. Connecting texture development to die design in extruded flat products
  13. Analysis of observability of a differential equation system describing a synchronous electromagnetic drive
  14. Fatigue behaviour of multi-spot joints of 2024-T3 aluminium sheets obtained by refill Friction Stir Spot Welding with polysulfide sealant
  15. Sensitivity of trace-element analysis by X-ray emission induced by 0.1-10 MeV electrons
  16. Reprint of
  17. Corrigendum to: Pathways to Implementation: Evidence on How Participation in Environmental Governance Impacts on Environmental Outcomes
  18. Joe Lederer: Das Mädchen George
  19. Editorial
  20. Experimental-numerical study of laser-shock-peening-induced retardation of fatigue crack propagation in Ti-17 titanium alloy
  21. The Cape Town Convention and the Space Assets Protocol
  22. Subsistence, Substitutability and Sustainability in Consumption
  23. Das Atom-Ei des Columbus
  24. Repeated 14CO 2 pulse-labelling reveals an additional net gain of soil carbon during growth of spring wheat under free air carbon dioxide enrichment (FACE)
  25. Measures to Safeguard and Enhance Soil-Related Ecosystem Services
  26. Is there a post-racism?
  27. Achieving high mechanical performance of the large-scale sand-casting Mg–4Y–x nd–y Gd–0.4Zr alloys by tailoring Nd and Gd contents
  28. Aufgaben 2.0
  29. Das Seufzen der Olimpia
  30. How self-regulation helps to master negotiation challenges
  31. Changes in butterfly movements along a gradient of land use in farmlands of Transylvania (Romania)
  32. The Influence of ISO 14001 and EMAS Certification on Environmental and Economic Performance of Firms: An Empirical Analysis
  33. Introduction
  34. Deformation-induced dynamic precipitation during creep in magnesium-tin alloys