title: Identification and age estimation of blood stains on colored backgrounds by near infrared spectroscopy.
abstract: Non-destructive identification and subsequent age estimation of blood stains are significant steps in forensic casework. The latter can provide important information on the temporal aspects of a crime. As previously shown, visible spectroscopy of blood stains on white backgrounds can successfully be used for their identification and age estimation. The use of this technique however, is hampered by dark backgrounds. In the present study the feasibility to use near infrared (NIR) spectroscopy was evaluated for blood stain identification and age estimation on dark backgrounds. Using NIR reflectance spectroscopy, blood stains were distinguished from other substances with 100% sensitivity and 100% specificity. In addition, Partial Least Squares Regression analysis was applied to estimate the age of blood stains on colored backgrounds. The age of blood stains up to 1 month old was estimated successfully with a root mean squared error of prediction of 8.9%. These findings are an important step toward the practical implementation of blood stain identification and age estimation in forensic casework, where a large variety of backgrounds can be encountered.
authors.affiliation: Department of Biomedical Engineering and Physics, Academic Medical Center Amsterdam, P.O. Box 22700, 1100 DE Amsterdam, The Netherlands. G.J.Edelman@amc.uva.nl
authors.forename: Gerda
authors.initials: G
authors.lastname: Edelman
authors.forename: Vicky
authors.initials: V
authors.lastname: Manti
authors.forename: Saskia M
authors.initials: SM
authors.lastname: van Ruth
authors.forename: Ton
authors.initials: T
authors.lastname: van Leeuwen
authors.forename: Maurice
authors.initials: M
authors.lastname: Aalders
mesh_terms: D001801:Blood Stains; D001834:Body Water / Q000737:chemistry; D003116:Color; D049429:Forensic Pathology; D006454:Hemoglobins / Q000737:chemistry; D006801:Humans; D008297:Male; D010108:Oxyhemoglobins / Q000737:chemistry; D012044:Regression Analysis; D012709:Serum Albumin / Q000737:chemistry; D012712:Serum Globulins / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D013997:Time Factors
chemical_list: D006454:Hemoglobins; D010108:Oxyhemoglobins; D012709:Serum Albumin; D012712:Serum Globulins