The use of stable isotopes in postconflict forensic identification

Abstract Stable isotope ratio analysis is becoming an extremely important tool for the forensic investigator. It can be particularly useful in missing persons investigations to help establish an unknown's identity by potentially reconstructing an individual's geolocational history, determining the number of individuals present in a case, and linking/separating remains from commingled assemblages. In this review article, we explore several main themes related to the use of stable isotopes in postconflict forensic identification. First, we describe what stable isotopes are and how global isotopic variation arises in human tissues via natural processes and cultural practices. Next, we discuss the selection of appropriate human tissue samples for examination based on testable hypotheses. We provide guidance on the options that exist for isotope sample preparation, analysis, and data handling; and finally, we examine which sample quality measures and quality assurance approaches should be used in isotope data reporting and interpretation. These themes are primarily presented to help the isotope data consumer understand the benefits and limitations of the technique that might not be apparent when sending samples to and receiving results from a high throughput, contract isotope testing laboratory. Real world examples of forensic stable isotope ratio analysis are provided within the article to highlight many of the concepts, particularly in regard to identification applications. This article is categorized under: Forensic Anthropology > Anthropology in Mass Disaster & War Crime Contexts Forensic Biology > Interpretation of Biological Evidence Forensic Chemistry and Trace Evidence > Emerging Technologies and Methods