This chapter provides detailed information on the elemental analysis of trace evidence such as glass, paint, soil, and bone.
In a criminal investigation, trace evidence is commonly encountered on a victim, suspect, or objects, but is easily overlooked. The main aim of trace-evidence analysis is to associate a suspect or victim to one another or to a crime scene. In order to achieve this, the examiner must determine whether the trace evidence found in one location originated from the same source as trace evidence or known samples from another location(s). Elemental analysis can be used for this purpose. Topics covered in this chapter for each of the four matrices include the following: sampling and sample preparation, analytical techniques, statistical analysis, and interpretation. Merits and drawbacks of various elemental analysis techniques (including laser ablation inductively coupled plasma mass spectrometry, laser-induced breakdown spectroscopy, and X-ray fluorescence, among others) are discussed. Specific examples are provided to illustrate usage and interpretation for each matrix of the application of elemental analysis to discrimination or sourcing problems from the literature. (publisher abstract modified)