Determination of microplastics in university interior environments

Currently, microplastics have been found in all environmental compartments around the world. The first evidence of the occurrence of these ubiquitous pollutants in the air dates to 2015, when a wet deposition study was carried out in Paris (France). Since then, microplastics have been reported in air samples from various regions, becoming an important concern as they represent a source of pollution that has been underestimated for many years. Indeed, they may pose a potential health risk due to respiratory exposure, although the current knowledge about their concentration, dispersion, transformation, and deposition is still limited. The main objective of this research was to study the presence of microplastics in air from indoor environments, where human exposure may be greater. Specifically, sampling was conducted in four areas of the Chemistry Section of the Faculty of Sciences at the University of La Laguna (Canary Islands, Spain). In each of the locations, Petri dishes containing stainless steel filters with a 50 μm mesh size were placed. After 12 hours of exposure, the dishes were recovered and stored until analysis. This procedure was repeated over an entire week, including the weekend. The filters were examined under a trinocular zoom magnifying glass to determine the shape, size, and colour of the microplastics found. Additionally, their chemical composition was established using micro-Fourier transform infrared spectroscopy. This simple passive sampling method effectively allowed for the evaluation of both the presence of microplastics and the fluctuation of their concentration over time according to the flux of people. Also see: https://micro2024.sciencesconf.org/559715/document