Different Analytical Methods of Para-Phenylenediamine Based Hair Dye

Abstract

Many cases of toxicity and mortality either due to accidental or deliberate ingestion of hair dyes were reported in Egypt, Sudan, Israel, Morocco, Saudi Arabia, India and Tunisia. In the field of forensic analytical toxicology, the identification and quantification of chemicals are essential in deaths related to intoxication. The aim of the present study is to conduct chemico-analytical characterization of para-phenylenediamine (PPD) based hair dye of (Black stone hair dye, SHD) currently used for dying hear in Egypt, to confirm the identification of its components, that may be potentially toxic on oral or dermal exposure, this study uses comparison between different analytical methods. The applied analytical methods were inductively coupled plasma/MS (ICP/MS), witch used to determine the metal components of the dye, high performance liquid chromatography/MS (HPLC/MS) and gas chromatography/mass spectroscopy (GC/MS) were used for qualitative and quantitative analysis of PPD in the dye. A derivatization method was applied by transforming PPD (aromatic amines) into corresponding imine derivatives. This compound was prepared by condensation of 4-methylbenzeneamine with benzaldehyed to give N-benzylidene-4-methylbenzene-amine, which is a very stable internal standard. ICP/MS analysis revealed that most metal components of hair dye are Be, Na, Al, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Cu, and Zr, where HPLC/MS analysis revealed that PPD is the main ingredient of SHD. Derivatization is necessary for accurate determination of PPD in hair dye by GC/MS method and this results could not be obtained by direct injection of dye (without derivatization).