Development of Analytical and Interpretational Protocols to Facilitate the Provenance Establishment of Polycarbonate Headlamps Lens Materials

• NCJ Number: 233494
• Journal: Journal of Forensic Sciences Volume: 56 Issue: S1 Dated: January 2011 Pages: S47-S57
• Author(s): Christopher D. May, Ph.D.; R. John Watling, Ph.D.
• Date Published: January 2011
• Length: 11 pages
• Publication Format: Article
• Publication Type: Report (Study/Research)
• Language: English
• Country: United States of America

Annotation

Despite the forensic significance of polycarbonate headlamp lenses, robust analytical protocols to facilitate their discrimination are scarce. In this study, laser ablation inductively coupled plasma mass spectrometry has been applied to the analysis of polycarbonate headlamp lenses with multivariate chemometrics techniques utilized to facilitate interpretation of the data.

Abstract

The analytical protocol involves the analysis of 46 analytes on material comprising the exterior surface of the lens. Using this data, it was found that although minor variation exists within a single headlamp lens, discrimination between lenses produced from a single manufacturing plant was still possible using iterative forward stepwise linear discriminant analysis processes. Discrimination between all headlamp lenses, with the exception of some lenses produced on the same day in a single plant, could be achieved using the analytical protocol. Furthermore, an interpretational protocol has been developed that has successfully classified all tested headlamp lens samples, within the discrimination limits of the analytical method. (Published Abstract)