If you drink bottled water, soda (or pop, depending on whether you are from Philadelphia or Pittsburgh), or a micro brew-beer in Dallas, Denver or numerous other American cities, you may be carrying an 'iso-signature',  a natural chemical imprint related to that geographic location.

Iso-signatures are a chemical in imprint in hair due to beverages may and could be used to track your travels over time, a new study suggests in the Journal of Agricultural and Food Chemistry.

Lesley Chesson and colleagues explain that the body removes hydrogen and oxygen atoms from water (H2O), and beverages containing water, and incorporates them into proteins, including the protein in hair. Hydrogen and oxygen exist in different forms, or isotopes. The proportions of those isotopes vary in a predictable way geographically, with higher values in low-latitude, low-elevation, or coastal regions, for instance, and lower values elsewhere.

Since manufacturers usually use local or regional water sources in producing beverages, isotope patterns in hair could serve as a chemical fingerprint to pinpoint the geographic region where a person has been.

iso-signatures
Hey, where have you been?  Oh wait, we know, because water, beer and other beverages contain natural chemical imprints related to geographic location that may help trace the origin of the drinks.  Only to help criminal investigators identify the travels of crime suspects, of course.  Photo: iStock

The scientists analyzed isotope patterns in bottled water, soda pop, and beer from 33 cities and found that patterns in the beverages generally matched those already known for the tap water. They noted that the isotope pattern in beverages tends to vary from city to city in ways that give cities in different regions characteristic iso-signatures. A person who drinks a beer or soda in Denver, Des Moines, or Dallas, for instance, consumes a different isotope signature than a person in Las Cruces, Las Vegas, or Laramie.

The finding may help trace the origin of drinks or help criminal investigators identify the geographic travels of crime suspects and other individuals through analysis of hair strands, the study suggests.