Elemental composition of hair as a marker for forensic human identification

Abstract

BackgroundHair is one of the most common evidence types found in criminal investigations. Analysis of human hair reveals the mineral composition accumulated within it over time spent in a specific area, thereby providing additional information for forensic identification. Materials and methodsTo identify patterns of the elemental composition of hair in territories with different natural and anthropogenic features, hair samples of 1238 residents and 217 corpses of Central Kazakhstan were studied. The determination of 14 chemical elements in hair by inductively coupled plasma atomic emission spectrometry were presented. The data were analysed in terms of place of residence, gender, age and condition. ResultsThe results showed that the concentration of trace elements like Cu, Fe, Cd, and As significantly differed among all regions (p < 0.05). The composition of hair samples obtained from women significantly differed from those obtained from men for certain major and trace elements (p < 0.05). Concentrations of Ca and Mg in men were significantly lower than in women (p < 0.05) and were decreasing with age (p < 0.05). ConclusionsThe present investigation revealed a relationship between the elemental composition of hair and the place of permanent residence of a person, formed under the influence of regional industrial complexes, and determining gender and age-related differences. These findings enhance the possibilities of forensic human identification.