Body fluids are evidence of great interest in forensics because they allow identification of individuals through the study of DNA. After reviewing the tests and the methods that are currently being used by forensic practitioners for the detection of body fluids (e.g. blood, semen, saliva, vaginal fluid, urine and sweat), and after showing their main drawbacks and limitations, this work focuses on the review of emerging spectrometric techniques applied for the forensic analysis of body fluids. These techniques include the use of ultraviolet-visible, infrared (IR), Raman, X-ray fluorescence and nuclear magnetic resonance spectroscopy and mass spectrometry for investigating blood, semen, saliva, urine, vaginal fluid or sweat. Although all these spectrometric techniques seem to have a high potential to differentiate body fluids prior to DNA extraction, IR and Raman spectroscopy have shown the most promising results for discriminating stains from body fluids.

Body fluids are evidence of great forensic interest due to the DNA extracted from them, which allows genetic identification of people. This study focuses on the discrimination among semen, vaginal fluid, and urine stains (main fluids in sexual crimes) placed on different colored cotton fabrics by external reflection Fourier transform infrared spectroscopy (FT-IR) combined with chemometrics. Semen-vaginal fluid mixtures and potential false positive substances commonly found in daily life such as soaps, milk, juices, and lotions were also studied. Results demonstrated that the IR spectral signature obtained for each body fluid allowed its identification and the correct classification of unknown stains by means of principal component analysis (PCA) and soft independent modeling of class analogy (SIMCA). Interestingly, results proved that these IR spectra did not show any bands due to the color of the fabric and no substance of those present in daily life which were analyzed, provided a false positive.

Consumer fireworks are a heterogeneous group of pyrotechnic items widely used by citizens around the world. There are a wide number of forensic cases related to consumer fireworks that require knowing their chemical composition and variety of designs to conduct accurate and comprehensive analyses. In this research paper, a selection of six consumer firework types (firecracker, rocket, pyrotechnic fountain, pyrotechnic battery, sparkler, and smoke bomb) is physically described and their anionic compositions are determined. Preblast (fuses and charges) samples and postblast residues of the different consumer fireworks were analyzed by CE in order to determine their anionic composition. Different types of chemical compositions in fuses and pyrotechnic charges were determined, although they were not related to any type of item. Additionally, several discrepancies were found between the analytical results and the declared item compositions. Regarding postblast residues, a huge variety of anions were identified and attributed to some unconsumed starting materials and different chemical reactions occurring during combustion.

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