The UK Home Office Centre for Applied Science and Technology (CAST), in collaboration with the Centre for Forensic Science (CFS) at the University of Strathclyde, Glasgow, Scotland, worked together on a strategic research project to evaluate existing chemical enhancement techniques for their applicability to footwear enhancement for marks made in blood, urine, and soil on various fabric surfaces. The James Hutton Institute, Scotland, contributed their expertise and comprehensive experience in soil composition and analysis to that aspect of the project work. The research was led by Professor Niamh Nic Daeid and Dr Katy Savage at CFS and Dr Helen Bandey at CAST. In addition, the research team explored the effects of different soil characteristics on the efficacy of the chosen enhancement reagents with Professor Lorna Dawson of the James Hutton Institute. The laboratory work was carried out by Kevin Farrugia while completing his Ph.D. at the CFS under the supervision of Professor Niamh Nic Daeid.
The purpose of the research was to scientifically and robustly evaluate and establish the appropriate enhancement techniques and to understand the mechanisms for the development of footwear impressions made in operationally relevant contaminants on different colors and types of fabric. This included establishing the topographical and physical characteristics of the fabrics and influences that these may have on the subsequent enhancement of the footwear impression. Scanning Electron Microscopy (SEM) of the various fabric types and the interaction of the contaminants with these fabrics provided insight as to how materials such as blood and soil penetrated into the materials (Figures 1 and 2). The ‘porosity’ of the fabrics was also assessed. In the case of wet contaminants (blood and urine) the surface morphology of the fabric had little effect on the enhancement abilities of the various reagents investigated, while the success of enhancement on footwear impressions in soil depended on both the soil type and on the fabric surface morphology.