New method could help disrupt opioid crisis

In a collaborative effort, researchers at the FIU International Forensic Research Institute (IFRI) and the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science have zeroed in on a unique component of heroin that could help zero in on the locations of origin for individual batches.

"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 recent study validating the effectiveness of the new method. "It's helpful for them to develop intelligence from heroin that is seized."

Heroin is one part of the opioid epidemic gripping the nation, claiming almost 13,000 lives in 2015, according to the U.S. Department of Health and Human Services. There are four regions around the globe known for producing heroin -- Mexico, South America, Southeast Asia, and Southwest Asia. If drug enforcement agents can determine where heroin entering the United States is manufactured, they can better target domestic and foreign law enforcement efforts.

Although the DEA has a signature program that is very advanced, the new work, conducted at IFRI and the UM Rosenstiel School provides an additional tool not previously available.

Examining heroin's chemical structure provides clues to the manufacturing process used to turn opium poppies to heroin, but if manufacturers from different regions adopt similar processes, it's harder to tell where a sample came from. What researchers needed was something unique in the heroin itself. Something the typical manufacturer wouldn't know to look for or care to mask. They zeroed in on the ratio of radiogenic strontium isotopes, which are naturally occurring in bedrock. Strontium isotopes can be found in different ratios among geographic regions depending upon the nature of geologic formation.

Using heroin samples of known geographic origin provided to them by the DEA, researchers were able to measure ratios of strontium isotopes in samples known to come from the four distinct regions where heroin is typically made.

"We developed robust analytical methods to measure trace elements in the heroin powder at very low levels as well as measure strontium ratios" said IFRI director Jose Almirall, the principal investigator of the study from FIU. "We demonstrated, for the first time, that strontium can be used as a chemical marker for geography and geology to differentiate heroin samples from different geographic regions."

"I am very excited to see the potential for a powerful new wrench in our toolbox for geochemical fingerprinting of heroin and other opioids," said Ali Pourmand, the principal investigator on the study from the UM Rosenstiel School, Department of Marine Geosciences. "Isotope geochemists traditionally use Strontium (Sr) isotopes to track the evolution of Earth's mantle and crustal rocks, and its oceans. In recent years, novel applications have emerged in the food and wine industries by using Sr isotopes to track the link between geology and what grows, is produced, and consumed above it. Our study pushes this new frontier to tracking the sources of heroin."