Isotope fingerprinting can be used to analyze a single strand of human hair for the purpose of determining a person’s location during recent weeks, months, and sometimes years. Obviously, this type of geographical tracking can be extremely useful to law enforcement when investigating murder cases.
These particular isotopes are found in the DNA-free keratin protein shaft of a hair, and contain a sequential record of dietary and metabolic behaviors of the contributor.
Stable isotope analysis (SIA) uses, for example, stable carbon, nitrogen, and sulfur isotopes of human tissues to learn a victim’s dietary preferences.
Properties of various municipal water districts, even in cities and towns adjacent to one another, or within a large metropolitan city with more than a single water supply, can provide water that is isotopically distinct from one another and from other local water sources. Therefore, using unique stable oxygen and strontium isotope signatures, SIA reveals the source of an individual’s drinking water (a person drinks local water and the isotopic record of the water is captured and retained their hair).
There are many uses for Stable isotope analysis (SIA), including:
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Food authenticity
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Sports doping
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Criminal forensics
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Archaeology
When used in conjunction—stable carbon, nitrogen, and sulfur isotopes, along with stable oxygen and strontium isotopes—investigators are armed with a formidable geolocation tool for pinpointing a region of origin, or the path of recent travels of a murder victim. This is especially helpful when an investigation involves unidentified human remains.
Other Uses
Sample analysis of illegal drugs can reveal their sources (location), discovering whereabouts of clandestine laboratories, and even the trafficking routes used by dealers.
Stable isotope forensics is also used help to determine whether drugs, explosives, fibers, and other evidence share a mutual foundation or past. It’s utilized to differentiate counterfeit products such as pharmaceuticals and food products from authentic articles, and it’s used to determine if an athlete has used drugs to enhance their performance.
The World Anti-Doping Agency requires stable isotope analysis for doping analysis in sports. It’s also used to detect steroid abuse in cattle.
Analyzers, such as Elementar’s AnthrovisION, are the devices and included software used to determine the origin of a sample.
Isotopes
Scientists divide isotopes into two main types: radioactive and stable.
Stable Isotopes
Stable isotopes, those used in criminal forensics, sports doping, and archaeology have a stable proton-neutron combination and do not exhibit signs of decay/radiation.
The stable isotopes used in the testing/analyzing described in this article are oxygen, hydrogen, sulfur, nitrogen and carbon.
Radioactive Isotopes
When an atom has too many or too few neutrons, it is unstable and decays. As a result, these isotopes emit radiation that includes alpha, beta, and gamma rays.
Radioactive isotopes are used in medicine, agriculture, food industry, pest control, archeology. Radiocarbon dating uses the carbon-14 radioactive isotope. In medicine, radioactive gamma rays are used to detect tumors inside the human body. Exposing food to a controlled level of gamma rays kills many types of bacteria.
