New Forensic Laser Technique Locks Hair in Time
Jim Moran, a geochemist at the Pacific Northwest National Laboratory (Richland, Washington), led a team of researchers in the development of a new laser-powered chemical analysis technique that can take dozens of samples from a single strand of hair and distinguish the chemical signatures of each.
Jim Moran, a geochemist at the Pacific NorthwestNational Laboratory (Richland, Washington), led a team ofresearchers in the development of a new laser-poweredchemical analysis technique that can take dozens ofsamples from a single strand of hair and distinguish thechemical signatures of each.
Because existing methods destroy small samples, theydon’t allow for exact time-based measurements. Using thenew technique, which breaks up material instead of scorchingit, carbon isotope measurements from human hair can betaken over time, revealing information about what people ate,whether they’ve traveled, and where they’ve been.
The technique is described in detail in a paper publishedby Moran and his team in the April 12 issue of RapidCommunications in Mass Spectrometry.
“The carbon you eat goes into your hair, so hair is arecord of carbon ratios. If you’ve been traveling, I couldguess which countries you’ve been to or what youate,” Moran said in a Wired online article, indicatingthat forensic scientists should find the techniqueuseful. Biologists exploring food pathways in microbes,and paleontologists using carbon-based data to lookat ancient environments may also find value in thetechnique.
In addition to carbon sampling, the laser-ablationsystem may also work with other chemical isotopes,including nitrogen, oxygen, and sulfur as Moran’s team isworking on developing those applications.
The Single-Bullet Theory Comes to New York – But Was it a Direct Hit?
November 22nd 2023Pete Diaczuk of John Jay College of Criminal Justice gave a recollection at EAS 2023 of a case he worked on in Manhattan involving a victim fatally shot, incomplete ballistic evidence, and the wrong gun recovered at the scene.
Chemometric Analysis on ATR-FT-IR Spectra of Spray Paint Samples for Forensic Purposes
April 1st 2022Spray paint is often used by vandals for creating graffiti, as well as for criminals to leave signs, messages, and blots to conceal the left traces at the scene of their efforts. Rajinder Singh and his colleagues in the Department of Forensic Science at Punjabi University (Punjab, India) have used attenuated total reflectance Fourier transform infrared (ATR-FT-IR) spectroscopy for nondestructive analysis of 20 red spray paints of different manufacturers, which could possibly be encountered at a crime scene, particularly in case of vandalism. Singh spoke to Spectroscopy about the findings, and the paper that resulted from their efforts.
