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Comparison of methods for visualizing blood on dark surfaces.
Jonathan Finnis1, Jennie Lewis, Andrew Davidson
1Cellmark Forensic Services, Abingdon, Oxfordshire, UK. JFinnis@Cellmark.co.uk
Science & Justice : Journal of the Forensic Science Society
|April 23, 2013
Summary
Hydrogen peroxide is the most effective method for detecting blood on dark surfaces. For dilute blood, luminol offers superior sensitivity, aiding forensic investigations.
Area of Science:
- Forensic Science
- Biochemistry
Background:
- Detecting blood on dark surfaces is challenging due to poor contrast.
- Current indirect methods are time-consuming and may miss crucial evidence.
Purpose of the Study:
- To identify a rapid, efficient blood detection tool for dark casework.
- To compare various methods for sensitivity, specificity, and DNA compatibility.
Main Methods:
- Evaluated luminol, fluorescein, hydrogen peroxide, UV light, and IR photography.
- Assessed methods on different surfaces and their impact on DNA analysis.
Main Results:
- Hydrogen peroxide demonstrated the highest overall effectiveness.
- Luminol showed greater sensitivity for detecting dilute blood stains.
Conclusions:
- Hydrogen peroxide is recommended for general blood detection on dark surfaces.
- Luminol is a viable alternative for trace or dilute blood evidence.
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