Paper No. 8
Presentation Time: 9:45 AM
FORENSIC APPLICATIONS OF STABLE ISOTOPES IN HUMAN HAIR
The stable hydrogen and oxygen isotopes of human hair are an archive of environmental food and water. Hair records strong geographic patterns, influenced by the stable isotope composition of local meteoric water. Stable carbon, nitrogen, and oxygen isotopes provide a record of diet. Dietary patterns have a regional bias but can be modified by long-distance trade patterns of the modern industrial era and can also be related to distinct cultural choices. Human hair grows at rates of about 1 cm per month and previous work shows that the stable hydrogen and oxygen isotope composition of hair segments are closely related to local drinking water and the travel movements of individuals. Temporal analysis of the stable isotope ratios in human hair can thus be used to demonstrate changes in geographic locations. This temporal travel information is useful in forensic investigations, particularly of unidentified murder victims. We will show examples from case studies across the United States.