Forensic approach for distinguishing species and sex of multispecies bloodstains in soil and sand by vibrational spectroscopy
- 1Universidad de Alcalá, Departamento de Química Analítica, Química Física e Ingeniería Química, Ctra. Madrid-Barcelona km 33,6, Alcalá de Henares, Madrid 28871, España; Universidad de Alcalá, Instituto Universitario de Investigación en Ciencias Policiales, Libreros 27, Alcalá de Henares, Madrid 28801, España
- 2Universidad de Alcalá, Instituto Universitario de Investigación en Ciencias Policiales, Libreros 27, Alcalá de Henares, Madrid 28801, España. Electronic address: [email protected]
Abstract
Bloodstains found at a crime scene must be accurately identified to correctly interpret the forensic context and events. Bloodstains (human or animal) sometimes appear on complex substrates such as sand or soil, which complicates their collection and analysis. Traditional presumptive tests for human blood may yield false positives in the presence of animal blood. This limitation, together with the need to preserve small stains, has motivated the use of non-destructive analytical techniques, such as vibrational spectroscopy. The aim of this work was to explore the combined use of ATR-FTIR, Raman microspectroscopy, and chemometrics for detecting and identifying human, dog, and cat bloodstains on sand and soil. ATR-FTIR and Raman spectral data were used to construct orthogonal partial least squares-discriminant analysis (OPLS-DA) models to assist in differentiation. In general, ATR-FTIR spectra combined with OPLS-DA demonstrated superior species discrimination capabilities compared with Raman spectra. Sex discrimination was further investigated using both datasets. However, the discriminatory performance of Raman spectroscopy was limited. These results highlight the potential of vibrational spectroscopy combined with chemometrics as a non-destructive approach for differentiating multispecies bloodstains on complex substrates. However, given the small number of donors included in this study, the findings should be considered preliminary, and further studies with larger sample sets are needed to confirm and extend these observations.
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BibTeX
@article{canotrujillo2026forensic,
title = {{Forensic approach for distinguishing species and sex of multispecies bloodstains in soil and sand by vibrational spectroscopy}},
author = {Cristina Cano-Trujillo and Gemma Montalvo and Carmen García‐Ruiz and Víctor Toledo-González},
journal = {Forensic Science International},
year = {2026},
month = aug,
doi = {10.1016/j.forsciint.2026.113082},
url = {https://doi.org/10.1016/j.forsciint.2026.113082},
note = {CC BY-NC-ND},
}
RIS
TY - JOUR
TI - Forensic approach for distinguishing species and sex of multispecies bloodstains in soil and sand by vibrational spectroscopy
AU - Cristina Cano-Trujillo
AU - Gemma Montalvo
AU - Carmen García‐Ruiz
AU - Víctor Toledo-González
PY - 2026
DA - 2026/08/02
JO - Forensic Science International
DO - 10.1016/j.forsciint.2026.113082
UR - https://doi.org/10.1016/j.forsciint.2026.113082
AB - Bloodstains found at a crime scene must be accurately identified to correctly interpret the forensic context and events. Bloodstains (human or animal) sometimes appear on complex substrates such as sand or soil, which complicates their collection and analysis. Traditional presumptive tests for human blood may yield false positives in the presence of animal blood. This limitation, together with the need to preserve small stains, has motivated the use of non-destructive analytical techniques, such as vibrational spectroscopy. The aim of this work was to explore the combined use of ATR-FTIR, Raman microspectroscopy, and chemometrics for detecting and identifying human, dog, and cat bloodstains on sand and soil. ATR-FTIR and Raman spectral data were used to construct orthogonal partial least squares-discriminant analysis (OPLS-DA) models to assist in differentiation. In general, ATR-FTIR spectra combined with OPLS-DA demonstrated superior species discrimination capabilities compared with Raman spectra. Sex discrimination was further investigated using both datasets. However, the discriminatory performance of Raman spectroscopy was limited. These results highlight the potential of vibrational spectroscopy combined with chemometrics as a non-destructive approach for differentiating multispecies bloodstains on complex substrates. However, given the small number of donors included in this study, the findings should be considered preliminary, and further studies with larger sample sets are needed to confirm and extend these observations.
SN - 0379-0738
SN - 1872-6283
ER -