16 Unravelling the impact of airborne fibres released from natural, bio-based and synthetic textiles on human lung health

Abstract Indoor air pollution from airborne micro- and nanoplastics, as well as natural particulate matter, is an emerging health concern. Released textile fibres and debris (eg during washing, drying, wearing) are a significant yet understudied source of this pollution. These fibbers, originating from synthetic, biobased, and natural fabrics, can be inhaled into the lungs. Particularly smaller fibres and debris (<3 um) can reach deeper lung regions, potentially posing risks to human respiratory health. Yet, the chronic effects of long-term exposure to environmentally relevant fibre concentrations in human lungs remain poorly understood. This project aims to investigate the long-term impact of inhaled textile fibers and debris on respiratory health using advanced reconstituted 3D in vitro lung models. We focus on synthetic, biobased and natural fibres under repeated subtoxic exposure conditions that simulate realistic human exposure scenarios. To achieve this, textiles undergo a controlled water-based gyrowash extraction (40°C, 45 min) and the released fibres and debris are collected, systematically characterized for their physicochemical properties and subjected to a comprehensive toxicological analysis. We will assess cell viability, ciliary function, mucociliary clearance, barrier integrity, and inflammatory responses. Specific endpoints include barrier tightness, cytokine production, and activation of inflammatory pathways, complemented by multiomics approaches to uncover toxicity mechanisms. The role of environmental pollutants adsorbed onto released fibres—particularly their interaction with the lung environment and their potential to amplify toxic and inflammatory effects—will also be investigated. This approach will enable fibre-specific hazard profiling and support realistic exposure and risk assessments.