Identification and Detection of Cosmetics Transferred during Close Personal Attacks

Many perpetrators are aware of the potential transfer of DNA to their victims and will try to limit its transfer. The applicant proposed an alternative means of identifying the perpetrator using cosmetics. The proposed research focuses on understanding the individualization power of glitter and shimmer components of makeup by identifying the unique features that can be used to compare cosmetic particles.

This project will also examine the transfer potential between two people or between a person and the crime scene.

"Note: This project contains a research and/or development component, as defined in applicable law," and complies with Part 200 Uniform Requirements - 2 CFR 200.210(a)(14). nca/ncf

Close personal assaults are a common occurrence and many perpetrators are aware of the potential transfer of DNA and will try to limit the transfer accordingly. However, many are not aware of the transfer and identification power of cosmetic components such as shimmer and glitter.

This project focuses understanding the individualization power of glitter and shimmer components by identifying the unique features that can be used to compare cosmetic particles. This project focuses on determining the transfer potential between two people or between a person and scene. In contrast to other studies, this project will focus on analyzing microscopic physical and chemical features that are unique to a sub-class. Additionally, since shimmer is comprised of naturally found mica, geolocation will be evaluated to determine the potential of locating where the mica was mined; providing another layer of individualization.

The first phase will characterize shimmer and glitter components and identify features unique to one sub-class. Due to their organic nature, shimmer samples will be characterized via PLM, FTIR, and XRD to determine the crystal’s structure and physical properties. DART-TOFMS and SEM-EDS will be used to analyze the composition of the shimmer’s coating. The metallic glitter particles will be analyzed by SEM-EDS and the polymeric samples analyzed by FTIR. The most unique features for discrimination will be determined using PCA and LDA, providing the foundation of classifying real samples. (19 months)

The second phase will focused on the primary transfer of these components between people and the scene. Effects of the environment on glitter and shimmer will be evaluated to ensure that the physical and chemical compositions do not change overtime. This will determine how long shimmer and glitter particles will remain on the assailant or at the scene after an attack. (9 months)

The third phase will focus on the characterization of real samples. Cosmetic particles will be isolated from the sample matrix for analysis. Thus providing an understanding of how similar or different the physical and chemical compositions are between manufacturing brands or if the same components are used by one manufacturer. (7 months)

The graduate student will lead the analysis at each phase as well as produce publications, presentations, and a dissertation presenting the findings. Data sets will be archived as .csv files at NACJD and the NCFS website for interested researchers. This classification scheme will lay the foundation for the evaluation of cosmetic evidence in close personal assaults.

"Note: This project contains a research and/or development component, as defined in applicable law," and complies with Part 200 Uniform Requirements - 2 CFR 200.210(a)(14) NCA/NCF