lectures
Responsible for
Advanced Environmental Chemistry
M.Sc. Environmental Sciences and M.Sc. Ecotoxicology, RPTU Kaiserslautern-Landau (formerly University of Koblenz-Landau),
since 12/2016
seminars
Co-responsible for
Einführung in die Methoden der Natur- und Umweltwissenschaften
B.Sc. Mensch & Umwelt, RPTU Kaiserslautern-Landau (formerly University of Koblenz-Landau),
since 10/2017
Assisting with
R for Beginners
10/2015–2/2016
lab courses
Co-supervising
Laborübungen Umweltanalytik
B.Sc. Umweltwissenschaften, University of Koblenz-Landau,
10/2021–4/2022
thesis supervisions
Examined
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Quantitative screening for polyethylene, polypropylene and polystyrene debris in mulched agricultural soils using pyrolysis-gas chromatography/mass spectrometry
Paul Löffler
Master’s thesis, University of Koblenz-Landau, Institute for Environmental Sciences, 2021
Although plastic pollution is receiving worldwide attention, most research targets aquatic
environments. Thus, knowledge gaps about the entry, fate, and transport of plastic particles in
terrestrial ecosystems are vast. Agricultural plastic covers are assumed to contribute to soil
contamination with microplastics by breaking down into smaller debris. Further, the lack of
simple and fast analytical methods might contribute to that since no standardized method for
the monitoring of polymer particles from soil matrices is available. Therefore, this work refined
and validated an already developed analytical method using pyrolysis-gas
chromatography/mass spectrometry (Py-GC/MS) for the detection of polyethylene (PE),
polypropylene (PP), and polystyrene (PS) debris form soil. Furthermore, the method was
applied to environmental samples from eight agricultural fields covered with different plastic
foils. For this purpose, 50 g samples were density separated, filtrated, and extracted prior to
thermo-analytical analysis. Moreover, to investigate the potential role of polymer debris as a
vector for pollutants, the sorption of two fungicides (cyprodinil and fludioxonil) to mulch foil
particles in aqueous solution was investigated in a 72 h batch experiment. In 63 % of the soil
samples at least one or a combination of the targeted polymers could be detected. But only
18.3 % of the showed higher polymer content than the respective detection limit. PE was most
frequently detected with concentrations up to 94.2 µg g-1, PP and PS were only sporadically
found. Different polymer contents could be found between tracks and furrows of the fields
mulched with perforated foil (p = 0.003). Furthermore, thinner mulching films were associated
with a higher plastic content in the soil, suggesting their avoidance for long-term applications.
However, the general polymer entry by one year mulch application was found in a low order of
magnitude compared to other sources such as sludge applications. Sorption of both fungicides
onto the plastic particles was only 5 % of the total amount. Thus, particles of this type are
considered no essential vectors for similar pesticides. Nevertheless, cyprodinil showed distinct
sorption compared to fludioxonil. This suggests lipophilicity as a driving factor for reversable
absorption. Future studies could investigate the surface dependent (ab-)sorption of such
pesticides to polymer particles to gain deeper understanding of the underlaying mechanisms.
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Veränderung der Kupfersorption im Boden durch Mikroplastikpartikel aus Reifenmaterial
Simon Rudolph
Bachelor’s thesis, University of Koblenz-Landau, Institute for Environmental Sciences, 2021
The potential consequences of tire abrasion being released into our environment have been rarely
studied. Although the wear of tires is one of the largest sources of microplastics. It is unknown whether
tire material can alter the sorption behavior of metals in soil, such as copper, which is often used as a
fungicide in organic viticulture.
To solve this question, this work investigated the sorption of copper to tire wear, to soil substrate, and
to a soil substrate-tire wear mixture in ultrapure water solution. In addition, the copper sorption of tire
abrasion in a soil solution was investigated to compare the results of the ultrapure water samples with
those of a somewhat more realistic experimental setup.
The results showed non-linear sorption of copper to the sorbents for all treatments, with a maximum
sorption of copper to tire abrasion in the range of 600 g·g-1. It was found that copper sorbed more
effectively to tire abrasion than to the soil substrate. Consistent with this, higher copper sorption was
observed in the mixed samples than in the soil samples. In the soil solution, sorption of copper to tire
abrasion proceeded less effective compared to sorption in the ultrapure water solution. This could be
explained by the presence of other dissolved ions and substances in the soil solution, which compete
with copper for the free sorption sites.
The work was able to show that tire abrasion in principle has the potential to alter the amount of copper
sorption in soils. At the same time, however, it was shown that the results of the laboratory samples
should not be overestimated with regard to an interpretation of sorption behavior in the real world. Many
influencing variables, such as the pH-value, the proportion of organic material in the soil, the aging and
degradation of the tire material as well as the chemical change of the tire material in the formation of
tire abrasion were not taken into account in this work and should be investigated in further work for a
better understanding of the processes taking place.
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Landwirtschaftliche Mulchfolien als Quelle für Makro-, Meso- und Mikroplastik in Ackerböden?
Heike Schröder
Master’s thesis, University of Koblenz-Landau, Institute for Environmental Sciences, 2021
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Microplastics in the effluent of a German wastewater treatment plant ‒ analysis with µ-FTIR spectroscopy
Minh Trang Nguyen
Master’s thesis, University of Koblenz-Landau, Institute for Environmental Sciences, 2020
Microplastic (MP) is of concern as an emerging pollutant in our plastic age because its ubiquitous
presence in the environment poses a potential risk to human and animal health. A better
understanding of MP pathways in the environment would benefit the development of mitigation
measures for plastic pollution. For this reason, this study investigated potential point sources of land-
based MPs into the aquatic environment, focusing on wastewater treatment plant (WWTP) effluent
and stormwater from the drainage sewer systems. With the River Weser as the study focus, MPs in
the effluent of the WWTP Bremen-Seehausen was monitored for one year to (1) determine the extent
to which treated wastewater (TWW) contributes MPs to the recipient and (2) capture the annual
variations of MPs. Also, water samples were taken from a runoff storage basin to (3) investigate MP
occurrence in stormwater and have it compared to that of TWW. In this study, MPs were isolated
from environmental samples through enzymatic-oxidative purification and subsequent density
separation with ZnCl2. For characterization, attenuated total reflection Fourier transform infrared
spectroscopy (ATR-FTIR) and focal plane array (FPA)-based micro-FTIR imaging were applied,
allowing the detection down to a size of 11.6 µm. Overall, MPs were present in all analyzed samples.
MP concentration in TWW varied throughout the studied year without a clear pattern.
Acrylates/polyurethanes/varnish/lacquer, polypropylene, polyethylene, ethylene vinyl acetate and
rubber were the most abundant polymers detected. MPs were dominant in subclasses with a size
range of 10-100 µm. There was no significant difference found between MP occurrence in TWW and
stormwater. In conclusion, this thesis provided a comprehensive data set of MP occurrence in TWW
with annual variations observed. Also, the contribution of stormwater to MP pollution in receiving
waters was elucidated, in turn emphasizing the need of studying MPs in stormwater.
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Screening for polyethylene, polypropylene and polystyrene microplastics in agricultural soil using pyrolysis-gas chromatography/mass spectrometry
Aaron Kintzi
Master’s thesis, University of Koblenz-Landau, Institute for Environmental Sciences, 2020
Although plastic pollution is receiving worldwide attention, research has mainly focused on
aquatic ecosystems, leaving a large knowledge gap on the sources, occurrence, fate and effect
of microplastics in terrestrial ecosystems. Especially the lack of adequate analytical methods
has so far hampered the mass-related quantification of microplastics in complex environmental
samples like sediment or soil. To quantitatively investigate the contribution of plastic mulching
to (micro)plastic pollution in agricultural soils a previously established method for the selective
quantification of polyethylene (PE), polypropylene (PP), and polystyrene (PS) in soil using
pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) was optimized, validated and
applied on soil samples. For this purpose, samples of 4 g soil from three strawberry fields
covered with different plastic mulches were extracted with 8 mL TCB at 120°C prior to
thermoanalytical analysis. To aid the understanding of the ecological impact of plastic
pollution in soil, a carbon transformation test according to OECD Guideline 217 was conducted
with five concentrations ranging from 0.05 to 500 mg g-1 of homogeneously mixed PE- and
PP-microplastics. The results of the plastic screening revealed increased PE concentrations of
up to 136 µg g-1 in at least one of the investigated fields. While it is likely that these plastic
contaminations originated from the mulch film, this could not be ultimately proven, as it was
not possible to exclude an input from other sources. Apart from that, valuable insights with
regard to future method optimizations were obtained. As the comparison of different
decomposition products indicated that especially longer-chained alkadienes are suitable for a
specific quantification of PE, 1,19-Eicosadiene was selected for PE analysis. On the basis of
solubility tests performed with several polymers and mulch films, a change of the solvent from
pure TCB to an n-Xylene/TCB mixture is recommended for future studies. The results of the
carbon transformation test revealed no significant effects of microplastics on soil microbial
activity compared to the control. A microplastic-driven increase in microbial activity, as
described by other authors could not be confirmed. Given that research on fate and effects of
microplastics in terrestrial ecosystems is in its infancy, there is still a long way to go for a
comprehensive risk assessment. Future studies are facing the challenge to extend analytical
analysis to other plastics and matrices and to consider more species in toxicological testing in
order to obtain a more complete picture of the consequences of plastic pollution.
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Adaption and development of purification methods to extract PE and PET microplastics from agricultural soil
Orasai Faikhaw
Master’s thesis, University of Koblenz-Landau, Institute for Environmental Sciences, 2020
Microplastic pollution of aquatic ecosystems is a rapidly evolving research topic, whereas the
issue on terrestrial ecosystems has been neglected. Presently, terrestrial ecosystems under
influence of human, such as agroecosystems, are possibly to be contaminated by plastic debris.
Nevertheless, the boundary of this contamination has not been determined at present due to
lack of adequate analytical methods for the quantification of plastic debris in soil.
With this thesis, I adapted, developed, and evaluated a suitable extraction procedure for the
quantification of poly (ethylene) and poly (ethylene terephthalate) in soil, which are the
potential microplastics agricultural soil. Suitability of TGA-MS for the detection and
measurement of PE microplastics in soil was also investigated. Various extraction methods
were conducted and achieved the recovery rate of -5% to 111%. To evaluate the performance
of TGA-MS for PE quantification, the several calibration standards were tested. The calibration
curves responded linearly (adj. R2 of 0.880-0.992) with instrumental detection limits of
0.40-1.61 mg PE and quantification limits of 1.21-4.87 mg PE. Overall, an appropriate procedure to
extract MPs from the soil sample should be a (sequential) density separation followed by SOM
digestion using Fenton’s reagent or dissolution combined with SOM removal using Fenton’s
reagent. Soils with different organic matter content, and with various kinds of microplastics,
and also the real agricultural soil are needed to be examined in further study.
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Penguins Eat Plastic Too
Paul Löffler
Project thesis, University of Koblenz-Landau, Institute for Environmental Sciences, 2020
The lack of simple methods for microplastic quantification in non-aquatic environments is deemed from a high concern in
times of increasing plastic littering, especially into terrestrial ecosystems. Hence, the first aim of this study was to improve a
pyrolysis GC-MS (gas chromatography mass spectrometry) method for plastic quantification using prior liquid extraction.
Therefore, the solvent properties of the targeted polymers were to be investigated. The second aim of the study was to adapt
the method towards the quantitative extraction of microplastic particles from penguin guano. Guano is assumed to have more
matrix interferences than soil because of it’s relatively high organic carbon content (8-15%). For the first aim, the solubility of
PE, PP and PS were tested in different solvent combinations, where TCB: xylene 50:50 was found the best. Furthermore, a
solubility limit for polyethylene fibers was determined to be 1500 µg/mL and during the experiment the assumption of a
cooling-induced coil-to-globule transition (CCGT) was built and strengthened. For the second aim of the study several clean-
up procedures were tested whereat quantitative filtration with demineralised water was found to have the highest recoveries. A
filter recovery experiment was carried out and averaged recoveries between 40.90 % ± 7.8 % for PP and 71.53 % ± 90.8 %
were obtained for PS. For the different PE pyrolysates averaged recoveries between 40.60 % ± 5.7 % for 1,20-henicosadiene
and 50.09 % ± 7.4 % for 1,22-tricosadiene were determined. This optimized method was then applied to penguin guano. In the
samples from the Antarctic no polypropylene exposure could be monitored. However, PE was quantified in seven of these
samples in amounts between 178 µg/g and 2236 µg/g guano. These findings support the existing method with a solvent
composition of TCB: xylene (50:50) and provide new indication (CCGT) for more accurate precision. Furthermore, the results
add another prove for the existence of plastic debris in the Antarctic. Consequently, the results highlight the need for further
assessment of plastic particles in this sensitive ecosystem. Especially temporal trends and potential effects on penguins and
other organisms in the arctic food web are to be investigated.
Co-supervised
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Entwicklung einer Methode zur Quantifizierung der Sorptionseigenschaften von 17α-Ethinylestradiol, Diethylstilbestrol und Gemfibrozil an Polyethylen-Mikroplastik
Sven Korz
Bachelor’s thesis, University of Koblenz-Landau, Institute for Environmental Sciences, 2019
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Combined strategy to remediate a lindane polluted soil with the white rot fungi Pleurotus ostreatus and biochar
Julius Albert
Master’s thesis, University of Koblenz-Landau, Institute for Environmental Sciences, 2018
Lindane is a persistent organo-chlorine insecticide which has been extensively used
worldwide for the control of agricultural, wood and medical pests, despite known its
tendency to bioaccumulate and its toxicity to non-target organisms. As a result of the high
persistence and long-time extensive usage, environmental contaminations of global
dimensions exist. To bioremediate these soils, different bioremediation strategies were
tested, based on biochar application, and degradation by the white rot fungi Pleurotus
ostreatus, and a combined approach using biochar and P. ostreatus. In order to simulate
realistic in situ remediation treatments, economically and feasible application rates and
typical lindane pollution levels were used. The efficiency and effectiveness of each
remediation treatment in non-sterile and sterile soils during 50 days of incubation was
evaluated according to lindane dissipation processes (extractable, non-extractable,
volatilized and mineralized radioactivity) and growth (ergosterol content) and activity
(respiration) of P. ostreatus and indigenous soil microbes. Fungal treatment and biochar
application showed best remediation success in terms of lindane dissipation either due to
mineralization or immobilization. Sterile soils were strongly colonized by P. ostreatus and
particularly high lindane mineralization (8.73-11.7 %) and immobilization (16.9-24.5 %)
were observed. Non-sterile inoculated soil showed a similar magnitude of immobilization
(10.54-24 %) but lower mineralization (2.4-2.7 %). However, the mechanisms of lindane
immobilization by P. ostreatus, i.e. whether lindane was only sorbed or also incorporated
into fungal tissue, still remains to be clarified. Biochar amendments resulted in lower
volatilization of lindane from soil and had a positive effect on fungal growth in terms of
respiration rate and visually observable mycelium. Moreover, it enabled a better
colonization of the non-sterile soil and therefore, biochar amendments might provide a
useful tool to introduce fungal inoculum for future in situ remediation measures. However,
the fungal growth (ergosterol content) and lindane mineralization were lower in biochar-
amended soils. This may be due to the strong sorption of mineralized lindane (14CO2) and
ergosterol to biochar, which might have resulted in lower recoveries by the methods used.
A lower extraction efficiency for ergosterol-spiked soils has already been demonstrated in
this study. It therefore remains to be clarified whether the biochar had a negative effect on
fungal growth and mineralization or whether this can be attributed to inadequate
extraction methods. Moreover, it should be examined to what extent common methods for
measuring the mineralization of a pollutant can be applied to biochar-amended soils, or
whether the methodologies must be changed for this purpose. In addition, it remains to be
clarified in the future to what extent these results can be transferred to a field trial.