Date of Submission


Document Type



Brooke Weinger Kammrath, Ph.D., D-ABC


Trace Evidence, Hair Analysis, Microscopic Hair Examination, Postmortem Root Banding, Antemortem Root Banding, Environmental Effects


Hair Analysis, Postmortem Changes


Trace evidence, Hair--Analysis, Postmortem changes


Microscopical hair analysis has become a controversial practice within forensic science primarily due to issues related to interpretation, and specifically overstating the significance of an association. The validity of microscopical hair comparisons has suffered from intense scrutiny by the forensic community, with one criticism being a paucity of peer reviewed research. An often-unrecognized aspect of microscopical hair analysis is its use in providing reconstructive information based on identifiable features. One example of this is postmortem root band or PMRB. PMRB is the formation of a band slightly above the root bulb and below the skin surface on the hair of cadavers. PMRB can be used as a tool to determine the presence of a cadaver at a crime scene, corroborate witness and suspect testimonies, and create a rough estimate of post mortem interval. The formation of PMRB is still a minimally researched topic with forensic hair analysts slowly investigating the formation of this root band. However, an even smaller amount of research focuses on antemortem root banding (AMRB), which is the formation of a root band in hair that has been sampled from living people. This AMRB is formed from environmental conditions with factors that are poorly understood. In this study, hairs were sampled (pulled) from voluntary individuals and analyzed with microscopic techniques before and after being subjected to various humidity, water, and temperature conditions. This experiment was completed in two phases, with the initial phase centered around the comparison of hairs in three conditions. These conditions were room temperature, body temperature with no added humidity, and a high temperature with high humidity. The second phase of this experiment focused on the comparison of hairs in room temperature conditions, high temperature and high humidity conditions, room temperature with added water conditions, and room temperature with added soapy water conditions. The results of this study indicate a need for further testing of AMRB formation in different environmental conditions.

Available for download on Saturday, May 11, 2024