Environmental impact of fibrous microplastics emitted from textiles during washing under the life cycle assessment framework

The massive employment of plastics in various industrial sectors has led to an uncontrolled increase and mismanagement of plastic waste, contributing to the rampant presence of plastics in the environment1 . Primary and secondary microplastics are a significant environmental and health concern due to persistence and ability to cross biological barriers2,3,4. Additionally, microplastics are an excellent vehicle for chemical additives and pollutants5,6. Microplastics represent a concerning environmental problem currently not addressed by the Life Cycle Assessment (LCA) methodology, the most common tool in evaluating the environmental impact of products, services, and activities. In recent years, several works have emerged to present a scientific approach to the quantification of the unitary environmental effects of microplastics through existing and novel impact categories7,8,9. In this project, a cohesive procedure was established, based on ISO 4484 series, for the simulation of a washing process, collection and filtration of effluents on silicon filters, and optical and chemical classification of emitted fibrous microplastics through μ-FT-IR spectroscopy. Spectroscopy results were compared to a gravimetric analysis. The spectroscopy analysis of PA6, PA6.6, PET, and PP samples revealed that fibrous microplastics of the same chemical species as the sample are equal to or less than 0.3% of the total emitted matter, confirming an extensive organic and synthetic material contamination. The quantity of emitted microfilaments doesn't significantly change between the first and third wash. An environmental assessment through the impact category "Physical effects on biota" 10, revealed that the direct emissions to the marine compartment of PET microfilaments from the polyethylene terephthalate sample have the largest impact at the midpoint and endpoint level, equal to 9.72e-01 PAF m3 day/kgsample and 2.65e-05 PDF m2 year/ kgsample.