Mag. pharm. Sarah Stellnberger BSc

Picture of Sarah Stellnberger


Thesis title: "Investigating the effect of bioplastic-derived micro- and nanoplastics on human health"

Thesis outline: Human activities have resulted in a significant amount of plastic in the atmosphere, land and water ecosystems, to such an extent that plastic waste will leave a fossil record for future generations. Emerging evidence suggests that humans are continuously exposed to microplastics through inhalation and ingestion. However, the potential health risks associated with these contaminants remain poorly understood. Micro and nanoplastics (MNPs) have been detected in various organs, such as the liver, spleen, kidneys, urine, bone marrow, brain, cerebrospinal fluid and placenta. In an effort to address plastic pollution, the introduction of biodegradable plastics aimed to offer an environmentally friendly substitute to conventional plastic. Bioplastics are polymers that possess either a biobased nature or the ability to biodegrade, or sometimes both.

Biodegradable bioplastics, when subjected to microbial degradation, are fully broken down without leaving detectable toxic remnants. However, biodegradation of these polymers needs optimized conditions of temperature, moisture and pH to initiate the expected degradation process. Consequently, when biodegradable bioplastics are not disposed and processed under controlled conditions, they accumulate in the environment and undergo fragmentation, resulting in the generation of MNPs and release of potential toxic monomers and oligomers. As the production of bioplastics continues to rise, it is expected that their contribution to plastic waste will increase and become comparable to that of conventional plastics.

This study aims to investigate the degradation products that occur during microbial and enzymatic breakdown of bioplastics and to identify and quantify the generated degradation products. Within the various working packages toxicological assessment as well as physico- chemical and physical characterization will be conducted. Furthermore, I will investigate the interaction of MNPs with bioavailable molecules and proteins and the feasibility of adapting labelling protocols used for MNPs derived from conventional plastics to those derived from bioplastics.

My intended research aims to address the critical knowledge gap regarding the effects of MNPs derived from bioplastics, which has been relatively unexplored in the scientific literature. Most of the existing research focuses on the potential impact of conventional plastics. Therefore, it is crucial to investigate the gastrointestinal fate and toxicity of bioplastics in order to generate groundbreaking data on the potential risks they pose to human health. The findings will contribute to a comprehensive understanding of MNPs in biological systems, ultimately aiding in the development of strategies to mitigate their potential risks. With this study I aim to contribute to the development of safe and sustainable plastic alternatives, promoting the concept of “safety by design” in the field of bioplastics. 

Supervisor: Verena Pichler, Advisor: Verena Kopatz (Medical University of Vienna)