Fibres are shed from new and used clothes every time they are washed.

Source: Pirc U, Vidmar M, Mozer A, Krzan A (2016) Emissions of micro-plastic fibers from microfiber fleece during domestic washing, Environ Sci Pollut Res Int 23:22206–22211

https://doi.org/10.1007/s11356-016-7703-0