By Andrew Schneider
That mug of microbrew you hoisted after work today tasted good, didn’t it? Would it have gone down as easy if you knew that it left a chemical marker showing what city you were in when you drank it? So do bottled and tap water as well as soft drinks.
It’s true. Your cellphone isn’t the only thing that can tell others your location. Scientists who can precisely measure hydrogen and oxygen isotopes can also tell where a crime victim spent the past year or whether that milk came from the farm down the road or across the country.
Biologists, geologists and analytical chemists at the University of Utah and a Salt Lake City laboratory called IsoForensics, Inc. are using this technology to help test food quality and solve cold cases for detectives around the country.
At the heart of the process is the water that is used in all beverages, from booze to baby formula. The body removes hydrogen and oxygen atoms from water and beverages that contain it and leaves a natural chemical imprint or fingerprint, explained Lesley Chesson and her colleagues in the current issue of the American Chemical Society’s Journal of Agricultural and Food Chemistry. “What we found is that human hair records the isotopic composition of the water that you drink,” she explained.
Chesson, an analytical chemist and the lead author of the study, explains it this way: The isotopes of hydrogen and oxygen in water vary in ways that can be predicted accurately, and they reveal the latitude, elevation and proximity to coastline.
Lesley Chesson
“A distinct chemical fingerprint in your hair could be used to track your travels,” Chesson says.
There are implications for this beyond tracking human whereabouts. It’s also a way to find fraudulent food.
The Utah team is collecting honeycomb from beekeepers across the country in hopes of tracking where honey originates. If this works, federal criminal investigators from Customs, the Food and Drug Administration and the Border Patrol will finally have a way to stop the smuggling of mislabeled, often unsafe Chinese honey.
It might also be a way to determine if that pricey bottle of wine is really worth it.
Three scientists from the University of Utah and IsoForensics – Jason West, James Ehleringer, and Thure Cerling have used the technique of measuring hydrogen and oxygen stable isotopes to detect and confirm the origin of wine. They found that the water in the wine does indeed provide a record of where the water came from—meaning the wines were clearly distinguishable by growing region.
The criminal-case uses for this technology is right out of CSI. The first case it was used on was that of a woman whose body was found in 2000 in an old bathhouse on the shores of the Great Salt Lake. It had been converted into a concert hall called Saltair.
Seven years after the woman was found, a few strands of her hair yielded a staggering number of details.
“We were able to get a snapshot of the victim’s life back through time…week by week, determine what she drank and thus her location during the period,” Chesson says.
For example, they found that the victim had made periodic moves in the two years leading up to her death, back and forth between two regions in Idaho and Utah every six or eight months.
Chesson began collecting water and hair samples from across the United States in 2007. Next she collected samples of beverages found in almost every community – Dasani brand bottled water, Coca-Cola Classic soda, and Budweiser beer.
The Utah team collected a database of the chemical characteristics of drinking water in 450 U.S. communities.
Chesson and her colleagues found that the soda, bottled and tap water offer a consistent and accurate database. (They found that Budweiser might not be a good way to track someone—the brewer, Anheuser-Busch Inc., operates 12 breweries in the U.S. A consumer could be tipping a Bud that traveled hundreds of miles to their local market.)
The team also collected milk and cow drinking-water samples from eight locations in six states and Puerility Rico then bought milk from supermarkets in 30 cities within 18 states. Yes, they can track the origin of that milk mustache.
Chesson and the other scientists from IsoForensics have put out the word to beekeepers across the U.S. to send in samples of well-identified honeycomb. so the group can refine a method to accurate identify where the honey originated. I’ve was writing about honey laundering before my former newspaper, The Seattle Post-Intelligencer, closed 14 months ago and since I began covering public health for AOL News.
Believe me the bogus honey continues to flow though U.S. and onto store shelves. Honest honey importers and packers, and there are many, are trapped between shady importers who actually bounce Chinese honey from country-to-country, or just falsify the shipping papers, and the inability to actually have the golden nectar tested for country-of-origin by any laboratory outside of Germany.
If the analytical wizards in Salt Lake City can develop and confirm the accuracy of this technique, federal criminal investigators from Customs, the Food and Drug Administration and the Border Patrol will have a long-sought-after tool in U.S. efforts to halt the smuggling of mislabeled and adulterated Chinese honey.
In May, I reported that Texas A&M University palynologist and an anthropology professor Vaughn Bryant said he is doing melissopalynology – the study of pollen in honey that allows identification of its country of origin. From what Chesson told me it sounds like IsoForensics approach could wind up being more accessible and perhaps less costly than the German process.
Once you get beyond the gee-whiz factor, the Utah team’s tracking technology has big-time implications for making sure any number of food products are safe, and accurately labeled.
Here is a link to a longer version of what I wrote today for AOL News .
(Kimberly Marlowe Hartnett contributed to this report.)
The ratio of isotopes of oxygen and hydrogen differ by geographic region.
