WARNING The use of this document involves hazardous substances, operations and equipment. It does not purport to address all of the safety or environmental problems associated with its use. It refers only to technical suitability and does not absolve the user from legal obligations relating to health and safety/environment at any stage. This document specifies a method for the qualification and quantification of certain quinoline derivatives in textile products by means of extraction with methanol and gas chromatography with mass selective detector or liquid chromatography with mass selective detector. The method is applicable to all kinds of textile products consisting of natural or artificially dyed textile fibres and fabrics. It is further applicable to dyestuff powder used as textile auxiliary for dyeing and printing.