Challenges of Microplastics: Contaminants Threatening Ecosystems and Human Health

Microplastics (MPs) have caused concern in the scientific community over the last decade due to their widespread distribution in the environment and their potential harmful effects that are not yet fully understood. MPs are solid, water-insoluble polymer particles containing additives and range in size from 1 mu m to 1 mm. So far, the presence of MPs has been detected in various parts of the environment such as soils, oceans, lakes, sediments, and even isolated areas like the Mariana Trench. Humans are exposed to MPs through the ingestion of contaminated food, with numerous studies showing significant quantities of MPs in drinking water, bottled beverages, salt, seafood, and more. While legal restrictions do not yet directly apply to MPs as a pollutant group, the EU directive aims to adopt a methodology for measuring MPs by 2024, intending to include them in the list of monitored pollutants. Existing methods for analysing MPs are still under development, but primarily include spectroscopic techniques such as FTIR and Raman spectroscopy, which can provide information on the size, number and shape of the particles as well as the type of polymer. Despite this progress, there are still no standardised methods to compare results from different tests, and quality control often relies only on blank tests to check and monitor external contamination of the sample. The main purpose of this review is to provide an overview of the methods of analysis and the challenges faced by researchers. By analysing different methods, such as destructive (pyrolysis) and non-destructive (e.g. spectroscopic methods), a broader insight into the nature of the polymers, the number, size, and shape of the particles is obtained. However, the lack of standardised protocols for sample preparation, analysis, and data processing hinders the comparability of results and reduces the reliability of the research. Therefore, it is crucial to prescribe the experimental conditions to ensure the quality of the research and enable meta-analysis and verification of the presence of MPs in different environmental matrices.