Rapid identification of phenylenediamine isomers in henna hair dye products by gas chromatography‐mass spectrometry (GC‐MS)

This paper describes a gas chromatography‐mass spectrometry (GC‐MS) procedure for identification and quantitation of phenylenediamine isomers in eleven commercial and traditional henna hair dyes. Our results indicate that p‐phenylenediamine (p‐PD), the least toxic diamine isomer, is most commonly present in the hair dyes selected for this study. While relatively low levels of p‐PD are observed in most commercial hair dyes, some traditional henna preparations appear to consist almost entirely of p‐PD. The presence of variable and unpredictable amounts of highly toxic and mutagenic p‐PD in many commercial and traditional hair coloring products sold in developing countries is a potential public health hazard.