Reliable quantification of microplastic release from the domestic laundry of textile fabrics

This study explores the significant variation in test methods used to quantify microplastic release from the domestic laundry of textile fabrics. A wide review of the existing methods is made, with the important characteristics of these methods identified and assessed. This includes reviewing the type of washing apparatus, filtration methods, quantification metrics and the influence of fabric samples on the reported release of microplastics from domestic laundry. Based on this review, a new method for the quantification of microplastic release was developed using existing textile testing equipment. The reliability of the method to consistently assess microplastic release was validated through an inter laboratory study involving 10 independent globally distributed laboratories and a filter efficacy in excess of 99% demonstrated. The study showed the method has good inter and intra laboratory qualities, thus indicating this method can be considered robust and reliable. Importantly the method has the potential to provide a standardised method to allow direct comparison of results for different laboratories and for different fabrics with a high level of confidence.