Identification of human hair stained with oxidation hair dyes by gas chromatographic-mass spectrometric analysis.

This paper describes the gas chromatographic-mass spectrometric (GCMS) analysis of oxidation hair dyes from human hair. Diamines from the dyes were directly extracted from the hair in basic solution and aminophenols were extracted after neutralization. Both extracts were derivatised with trifluoroacetic anhydride and analysed by GCMS. Five components of oxidation hair dyes namely, p-phenylenediamine, toluene-2,5-diamine, o-aminophenol, m-aminophenol and p-aminophenol were clearly identified, whilst no other compounds originating from the hair dyes were detected. The presence and relative amounts of these dye components from hair extracts may assist in the discrimination of human hair especially in cases involving forensic science.