The strontium isotopic composition of heroin powder from four major regions on the planet shows potential for discerning its source origin. Photo: University of Miami

The Drug Enforcement Agency (DEA) probably didn’t envision help for the heroin crisis coming from the department of marine and atmospheric sciences at a Florida university, but that’s exactly how it played out earlier this fall when researchers there turned to elemental analysis of bedrock for clues.

Working with the FIU International Forensic Research Institute, researchers in the University of Miami’s School of Marine and Atmospheric Sciences zeroed in on a unique component of heroin that could help the DEA and other law enforcement agencies determine the drug’s origin location.

There are four regions in the world known for producing heroin, which comes from the poppy plant—Mexico, South America, Southeast Asia and Southwest Asia. However, it’s the United States that has a serious heroin crisis currently. Law enforcement agencies believe they can establish better targeted programs if they knew where the heroin that crosses into the U.S. is manufactured.

“The DEA wanted to know specifically whether elemental analysis could determine where heroin was coming from,” said Joshua DeBord, a chemistry Ph.D. student at FIU, who is a co-author of the paper published in Inorganica Chimica Acta. “It’s helpful for them to develop intelligence from heroin that is seized.”

So, DeBord and his team turned to bedrock—specifically the ratio of radiogenic strontium isotopes in said bedrock, which can be found in varying ratios among geographic regions depending on geologic formation.

Traditionally, geologists use strontium isotopes to track the evolution of Earth’s mantle, crust and oceans. In recent years, strontium isotopes have also been helpful to the food and wine industry, allowing growers to trace the link between geology and which crops grow, and which don’t.

Using strontium as a chemical marker to differentiate heroin samples from various geographic regions is a brand new application, though.

The researchers used heroin samples of known geographic origin provided by the DEA to establish a baseline of strontium isotopes from the four regions heroin typically hails from. In the study, the researchers pioneered multiple analytical methods to measure trace elements in the heroin powder at very low levels, as well as strontium ratios. Resulting profiles were successfully developed, and now geochemical fingerprinting is a tool the DEA did not have at its disposal before.

Additionally, unlike the drug’s chemical structure—which can be altered—the ratio of strontium isotopes is not something a typical heroin manufacturer would want or know how to mask. Thus, geochemical fingerprinting can provide an added layer of unchanged information, providing the DEA with more avenues to disrupt the nation’s opioid crisis.