A hair can tell what you ate, where all you travelled.

A hair can tell what you ate, where all you travelled.

Times of India Bangalore, May 28, 2009 

 

Variation in sulphur concentration in the hair can reveal one’s recent diet and the places one has been to. A new laser tool based on this can be very handy to investigators tracking terrorists. This tool shows up changes in a person’s eating habits and his or her movements between different countries. Known as the "laser ablation" method, it detects variations in the sulphur isotopes of a chemical throughout the length of a single human hair. Researchers from LGC Chemical Metrology Lab and University of Oviedo in Britain and Spain, respectively, who developed this method, focused on the most abundant sulphur isotopes in hair keratin, sulphur-32, which accounts for about 95% and sulphur-34, which makes up around 4%. This proportion can change in response to people’s diets and if they travel from one country to another. The laser works by making contact with the selected hair fragment, generating an aerosol, which later ionizes within plasma, with the spectrometer providing the exact proportions of the sulphur isotopes.