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A Quantitative Method for Determining a Representative Detection Limit of the Forensic Luminol Test for Latent Bloodstains

NCJ Number
Forensic Science International Volume: 278 Dated: September 2017 Pages: 396-403
Date Published
September 2017
8 pages
This article reports on the development of a quantitative method for determining the relationship between the amount of blood present and its reaction with luminol by measuring, under controlled conditions, the resulting chemiluminescent intensity with a video camera, combined with processing of the digital intensity data.

The luminol test has been used for just over 60 years by forensic investigators for presumptive identification of blood and visualization of blood splatter patterns. Multiple studies have estimated the limit of detection (LD) for bloodstains when luminol is used, with results ranging from 100 to 5,000,000 dilute; however, these studies typically have not identified and controlled important experimental variables that may affect the luminol LD for bloodstains. Without control of experimental parameters in the laboratory, variables that affect the potential of presumptive bloodstain test methods remain largely unknown, and comparisons required to establish new, more powerful detection methods are impossible. The method developed in the current project resulted in an estimated LD for bloodstains on cotton fabric at 200,000 diluted blood with a specific luminol formulation. Although luminol is the focus of this study, the experimental protocol used could be modified to study effects of variables using other blood detection reagents. (publisher abstract modified)

Date Published: September 1, 2017