Roundtable on „Microplastic Analysis Harmonization” in Austria

On November 24, 2025, BOKU University organized a workshop on “Comparison and harmonization of methods for microplastic analysis in Austria's rivers and soils”. At the beginning an overview of projects dealing with microplastics in rivers and soil was given. Afterwards, the common analysis methods used in Austria and the international research landscape to detect and quantify microplastics were presented, along with detection limits, advantages and disadvantages. These included microscopic, spectroscopic, thermos-analytical and other methods that provide either particle-based or mass-based results. The participants then presented their own projects, focusing in particular on problems encountered during sampling, preparation, and, above all, analysis. These were then discussed, and attempts were made to find solutions.

Another important outcome of the roundtable discussion was that the existing standards by no means cover all the necessary areas of sampling, sample preparation, and analysis. Intensive communication between working groups and further harmonization and standardization is urgently needed.  Selected major challenges like representative sampling, quality assurance and control, harmonized reporting of results was addressed and solutions were developed and documented.  A future goal would be to establish a cross-matrix (soil-rivers) database for metadata and, subsequently results.

However, there are still too many unresolved issues such as how to make measurement results more comparable when analyses are performed with different devices and evaluations are based on different databases and software, and there are for example no limits for match qualities for measured spectra .Since all participants were very interested in solving that issues and considered the exchange between experts as greatly enriching they agreed to stay in contact and meet at regular intervals to further discuss on the improvement and harmonization of microplastic analysis. All in all, the roundtable was a great success.