REVIEW Forensic analysis of dyed textile fibers John V. Goodpaster & Elisa A. Liszewski Received: 17 April 2009 / Revised: 28 May 2009 / Accepted: 29 May 2009 / Published online: 20 June 2009 # Springer-Verlag 2009 Abstract Textile fibers are a key form of trace evidence, and the ability to reliably associate or discriminate them is crucial for forensic scientists worldwide. While microscopic and instrumental analysis can be used to determine the composition of the fiber itself, additional specificity is gained by examining fiber color. This is particularly important when the bulk composition of the fiber is relatively uninformative, as it is with cotton, wool, or other natural fibers. Such analyses pose several problems, including extremely small sample sizes, the desire for nondestructive techniques, and the vast complexity of modern dye compositions. This review will focus on more recent methods for comparing fiber color by using chromatography, spectroscopy, and mass spectrometry. The increasing use of multivariate statistics and other data analysis techniques for the differentiation of spectra from dyed fibers will also be discussed. Keywords Forensic science . Textile fibers . Fiber dyes . Trace evidence The forensic significance of textile fibers Trace evidence is a generic term that can be broadly defined as “small, often microscopic fragments of various types of material that transfer between people, places and objects, and persist there for a time” [1]. Given this definition, trace evidence can consist of a vast array of materials such as hair, fibers, paint, soil, glass, pollen, and dust. In the context of a criminal investigation, trace evidence is inherently associative. Its forensic significance stems from the fact that transfer of trace material can link suspects, victims, and crime scenes by implying contact between two individuals or between individuals and objects. Textile fibers are arguably one of the most important forms of trace evidence given that they have many classifications and subtypes, are physically and chemically differentiable, have various processing procedures, and are transferred easily. Various characteristics are evident in fibers, and certain ones play significant roles in fiber analysis. One of the most important characteristics for fiber comparisons is color, which reflects the dyes and pigments that were used on the fabric. In fact, the only characteristic of many fibers, such as cotton, that can be reliably used for discrimination of samples is its color as generated by a fiber dye. Perhaps the most important treatise in this area is Forensic Examination of Fibres, edited by James Robertson and Michael Grieve, the second edition of which was published in 1999 [2]. Forensic fiber examiners have also established several working groups such as the European Fibres Group (EFG), which is a part of the European Network of Forensic Science Institutes (ENFSI). The EFG published the Manual of Best Practice for the Forensic Examination of Fibres in 2001, and Wiggins has summa- rized this and other efforts of the EFG during its first ten years (1993–2002) [3]. In the USA, the Scientific Working Group for Materials Analysis (SWGMAT) published the “Forensic Fiber Examination Guidelines” in 1999 [4]. Following review articles by Wong in 1989 [5], Rendle and Wiggins in 1995 [6], and Grieve and Wiggins in 2001 [7], there do not appear to be any recent reviews of the literature concerning the current analytical methods that may be applied to dyed fibers. Hence, it is the goal of this Anal Bioanal Chem (2009) 394:2009–2018 DOI 10.1007/s00216-009-2885-7 J. V. Goodpaster (*) : E. A. Liszewski Department of Chemistry and Chemical Biology, Forensic and Investigative Sciences Program, Indiana University Purdue University Indianapolis (IUPUI), Indianapolis, IN 46202, USA e-mail: jvgoodpa@iupui.edu