project

Does Environmental Weathering Alter the TGA-GC/MS Fingerprints of Microplastics?

Microplastics have become a growing concern in aquatic environments due to their potential impact on ecosystems and human health. However, reliable identification of microplastics remains challenging, as environmental particles differ substantially from pristine reference materials due to aging and weathering processes. This project aims to investigate how environmental weathering affects the polymer and as a result its behaviour during thermo-analytical detection using TGA-GC/MS. Identification of the polymer might become hampered. By generating environmental data, this research supports more reliable monitoring strategies and contributes to improved risk assessment and policy development.

Problem and Project Idea

Microplastics are increasingly detected in surface water, wastewater, and drinking water systems, yet their accurate identification remains challenging. Environmental aging and weathering processes alter the physical and chemical properties of polymers, which can lead to deviations from reference fingerprints and affect detection reliability. This project addresses the need to understand how such transformations influence thermo-analytical polymer fingerprints and the accuracy of microplastic identification in complex water matrices.

Research Approach

We will systematically investigate the effects of environmental weathering on polymer degradation and its effect on the behaviour using thermogravimetric analysis coupled with gas chromatography–mass spectrometry (TGA-GC/MS) and complementary LDIR spectroscopy. Both pristine and environmentally weathered polymers will be analysed. We will apply several different weathering approaches, including long-term outdoor rooftop exposure and freshwater pond exposure, with sampling after 3, 6, 9, and 12 months. This approach allows us to evaluate how realistic environmental conditions modify analytical fingerprints and affect polymer identification.

Expected Outcomes

This project will provide insight into how environmental weathering effects thermal degradation behaviour and characteristic fingerprint of polymers during analysis. The results will improve the robustness of fingerprint-based polymer identification methods, generate reference data for weathered microplastics, and support more reliable monitoring and assessment of microplastic pollution in water systems.

Image 1. Overview of the environmental weathering setups applied to polymer samples. Some polymers were placed in nylon teabags and exposed directly to all outdoor weather conditions. Others were enclosed in quartz glass vials filled with ultrapure water and exposed to natural sunlight, while an additional set of samples was placed in quartz glass vials without water to isolate the effect of UV radiation only. Further samples were deployed in nylon teabags in a freshwater pond at a defined depth, allowing controlled UV exposure under realistic water conditions. Together, these setups enable the assessment of multiple realistic environmental weathering scenarios.