Effects of polyester microfibres released from a domestic dryer machine on human lung organoids and Xenopus laevis

Washing synthetic clothes and textiles releases microplastics into the environment with the discharged water. However, microfibre emissions from dryer machines into air and waterways are still poorly investigated. This study aims to characterise and quantify the release of polyester fibres from a domestic dryer machine and to analyse their effects on two test models representing potential targets of freshwater and airborne contamination; the animal model Xenopus laevis (early development stage of a frog) and an innovative 3D model consisting of human lung organoids. Organoids are the most advanced in vitro models but are not yet applied to evaluate the biological effect associated with microplastic exposure. For this study, a variety of polyester clothes and tissues was washed and dried. Characterisation of morphology and hydrodynamic behaviour of released fibres into the air filter (0.4 g/kg dry weight) and into discharged water was performed by optical microscopy, SEM-EDS and DLS. The models were exposed to the environmentally relevant polyester fibres in various concentrations (1, 10 and 50 mg/L) and incorporation phenomena and effects were analysed by SEM and confocal microscopy. Preliminary results show ingestion of large amount of fibres by the animal model and an unexpected interaction between lung organoids and microfibers. More information on the effects will be presented at the conference. In addition to the implications of the results, the applicability of the used human organoids as test models for microplastic exposure will be discussed.