Recently, cases have been reported of pigmented contact dermatitis from cotton flannel nightdresses caused by naphthol AS as an azoic coupling component. In this study, a method for the quantitative determination of naphthol AS in cotton flannel nightdresses was developed involving the use of anion exchange resin adsorption and gas chromatography. The chromatographic behavior of naphthol AS on an anion exchange resin was examined in order to eliminate many of the interfering compounds often present in sample extracts. The eluent and the anion type of the resin were discussed. The analysis showed that the content of naphthol AS was above 1000 ppm in most samples.
