Interactions of Microplastics and Micropollutants in Water and Agricultural Soils

The international Doctoral Program Environment Water (ENWAT) of the Faculty of Civil and Environmental Engineering Sciences University of Stuttgart Germany in collaboration with the German Academic Exchange Service (DAAD) opens a call for max. 2 PhD positions for research in Environment Water. Each project involves high-quality research and state-of-the-art techniques and is supervised by excellent researchers. We are looking for highly motivated and talented students with a passion for science. Candidates must demonstrate an excellent performance in their previous academic education.

Title:Interactions of Microplastics and Micropollutants in Water and Agricultural Soils

Advisors: Prof. Dr. Patrick Brutigam (TUC) PD Dr. Claus Haslauer (VEGAS) Dr. Tobias Junginger (VEGAS) Dr. Manuel Deggelmann (TUC)

Research group / department

Department of Technical Environmental Chemistry and Sensor Technology (TUC) at the Institute for Sanitary Engineering Water Quality and Solid Waste Management (ISWA) and

Research Facility for Subsurface Remediation (VEGAS) at the Institute for Modelling Hydraulic and Environmental Systems (IWS)

Keywords: Microplastics Micropollutants Water Soil Environment

Introduction / Background

Microplastics are ubiquitous in the environment due to their versatility and the large quantities in which they are produced and used. At the same time global consumption and industrial production continue to rise not only of plastics but also of synthetic chemicals. As a result the number and amount of so-called micropollutants in the environment are steadily increasing. Among these micropollutants per- and polyfluoroalkyl substances (PFAS) are of particular concern. Like microplastics PFAS are highly persistent mobile and widely distributed even in remote areas. Both substance groups pose significant challenges for environmental and human health protection. Microplastic contamination is increasingly being detected on agricultural land. Sources include the direct application of plastic films used for crop production as well as inputs from sewage sludge and compost which are commonly applied as soil conditioners and fertilizers.
In addition to the plastics themselves these inputs often carry other micropollutants such as pesticide and fertilizer residues as well as PFAS. This study focuses on agricultural fields near Rastatt. The Rastatt case is one of the largest known PFAS contaminated areas in Germany (1200 ha) originating from the application of sludges from the paper industry (Bierbaum et al.).

Microplastics are known to act as carriers for various micropollutants (Yu et al.) as many substances can adsorb to their surfaces leading to localized concentration hotspots. However many questions remainparticularly concerning the adsorption of PFAS to microplastics and the conditions under which desorption may occur. Little is known about how environmental ageing and transport affect the sorption behavior of plastic arable soils key knowledge gaps include: How does the adsorption of pollutants change with plastic weathering To what extent do desorption and leaching occur What transport processes govern the mobility of microplastics and their associated pollutants in the soil

References

• VockenbergT. Wichard T. Ueberschaar N. Franke M. Stelter M. Braeutigam P. The sorption behaviour of amine micropollutants on polyethylene microplastics impact of aging and interactions with green seaweed Environ. Sci.: Processes Impacts 2020 22 .
• Yu Y. Yin Mo W. Luukkonen T. Adsorption behaviour and interaction of organic micropollutants with nano and microplastics A review Science of The Total Environment 2021 .
• Bierbaum T. Klaas N. Braun J. Nrenberg G. Lange F.T. Haslauer C Immobilization of per- and polyfluoroalkyl substances (PFAS): Comparison of leaching behavior by three different leaching tests. Science of the Total Environmentdoi: 10.1016/.

Research goals

• Investigate the interactions of microplastics and micropollutants with a focus on pesticides and PFAS
• Assess the transport behavior of microplastics in the soil layer
• Examine leaching and desorption processes of micropollutants from microplastics especially in relation to ageing and weathering and environmental weathering

Methods to be used

• Adsorption and desorption experiments of selected pollutants with new and artificially aged microplastics.
• Soil column experiments to study microplastic transport
• LC-MS for target analysis and non-target screening of micropollutants and degradation products in leachates

Prerequisites

• MSc in chemistry environmental chemistry analytical chemistry environmental engineering/sciences geo-hydrology or similar
• Knowledge about micro plastics and/or micro pollutants
• Experience in analytical chemistry and contaminant hydrogeology
• Willingness to develop scientifically and motivation to learn new concepts

Further Prerequisites:

• Resume/CV showing the applicants background professional skills a list of publications and oral and poster presentations as well as additional achievements (scholarships awards etc.)
• . Dipl.-Ing. or equivalent degree in Civil Engineering Water Resources Management Environmental Engineering or related sciences
• . in Civil Engineering Water Resources Management Environmental Engineering or related sciences

Copies of Certificates and Transcripts including all undergraduate level certificates and university degrees. All documents which are not in English or in German must be accompanied by copies of a legally certified English translation (for the application we will accept copies; but please be aware that originals or legally certified copies will be needed for the final case any differences between the copies and the originals show up the application will be dismissed.)

Please make sure that the copies of the transcripts show not only the grades but also explain the home grades system (please add copy of the description of grade scale).

• At the time of nomination to the DAAD (Dec 2025) generally no more than 6 years should have passed since the last degree was gained.
• Only international (non-German) applicants can be accepted. At the time of nomination to the DAAD (Dec 2025) the candidate must not have been resident in Germany for more than the last 15 months.
• Unless native speaker: proficiency in English (e.g. TOEFL IELTS etc.) or proof that . and . programs were held in English.
• 2 Reference letters from university professors from the applicants home university issued during the last 2 years.
• Motivation letter describing the applicants work experience and research goals (1 page)
• Summary of all relevant information about the applicant (1 page) - please upload it in the slot designated for the third reference.

Research Environment

• Agile and versatile research environment
• Well-equipped workstations and laboratories
• Nice helpful and interdisciplinary team for professional exchange and pleasant working conditions
• Co-supervised at two complimentary departments with foci on environmental/analytical chemistry and transport in porous media