Meanwhile everybody knows about the existing of microplastic and its negative impact on the environment. Studies have shown that microplastic is released during textile laundering that cannot be retained by wastewater plants. Against this background, the new DIN Spec 4872 created by Hohenstein represents a standardized test procedure for determining and classifying the environmental impact of textiles during laundering. Therefore, textiles are classified in terms of fibre release during the washing process with the aid of a suitable analysis system. In addition, the microfibre discharge is further classified by testing its biodegradability in waste water and determining the degree of degradation within a defined period of time. Finally, a suitable ecotoxicity test is carried out, to determine the toxicity of the residues after the biodegradation process. This new standard enables companies to test, evaluate and compare their textile product developments for the first time, regarding the fibre release during washing and the environmental impact of this fibre release. Thus, after testing and classification, an optimisation of the product portfolio and at the same time a more targeted product development can take place, as the environmental impact can be actively and consciously controlled.