Article Text

Download PDFPDF

Use of benzidine for histological demonstration of haemoglobin in human bite marks.
  1. R T Allison,
  2. D K Whittaker
  1. University of Wales, College of Medicine, Dental School, Heath Park, Cardiff.


    Macroscopic evidence of bruising from human bite marks may be inconclusive and routine histochemical methods of showing extravasated erythrocytes can be unreliable. Leuco patent blue staining, for the presence of peroxidase, Amido black B, a tinctorial staining method for haemoglobin, Perls's reaction for ferric iron (haemosiderin), Masson-Fontana for melanin, Masson's trichrome, a connective tissue strain, and the benzidine reaction for haemoglobin peroxidase were carried out in three forensic cases and one experimental case. A modified benzidine method was the most reliable indicator of haemoglobin activity, especially where dispersion into extra-cellular tissues had occurred. The resilience of the erythrocyte peroxidase enzyme to temperature changes and fixation supports the concept of a "pseudo-peroxidase" in those cells. It is concluded that free haemoglobin from bite marks, or indeed other forms of blunt trauma, may best be shown by the benzidine reaction and that exemption certificates for use of this prohibited substance may be worth pursuing.

    Statistics from

    Request Permissions

    If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.