In 2011, fentanyl was a public announcement of caution to law enforcement, clinicians, medical examiners, laboratory personnel and other related communities. Then it hit the streets, doubling 12-fold by 2016 and continuing to rise in the ensuing years. Last fall, the Center for Forensic Science Research & Education issued a similar “Potent Synthetic Opioid” warning for isotonitazene—and now law enforcement and crime lab technicians are starting to see the opioid reflected in drug samples.
Isotonitazene was first synthesized and reported in the literature in the 1950s. Based on structural modifications, isotonitazene appears to have potency greater than that of fentanyl. However, there has been little research about isotonitazene, or “iso.”
“The toxicity of isotonitazene has not been extensively studied but recent association with drug user death leads professionals to believe this new synthetic opioid retains the potential to cause widespread harm and is of public health concern,” reads the announcement from the Center for Forensic Science Research & Education (CFSRE).
According to CFSRE, isotonitazene is dissimilar in structure to common synthetic opioids forensic scientists typically encounter in casework, including fentanyl analogues and U-series analogues. Of isotonitazene’s similar analogues etonitazene, metonitazene and clonitazene, etonitazene is reported to be the most potent, followed by isotonitazene and metonitazene.
Although CFSRE has noted the presence of isotonitazene in drug samples, the Drug Enforcement Agency has yet to include it on the controlled substance list or the Emerging Threat Report. In addition to further research to understand its potency, Chris Thomas of the Knox County Regional Forensic Center in Tennessee told a local news outlet that his department needed a specialized test to confirm the presence of the opioid.
“It shouldn't be ignored,” Thomas said. “While it's a minimal amount of cases, it's one of those things if left undocumented, unregulated and unresearched, it can easily take over in the next few years as the emerging drug.”
Some forensic labs and coroners are already preparing for the arrival of the next big synthetic opioid. Lakshmi Sammarco, a coroner in Ohio, recently told the Cincinnati Enquirer that she plans to add a test for isotonitazene to toxicity screens for those who die from overdoses in her jurisdiction. She also said her department may revisit recent overdose deaths where the toxicology screen came back with no matches to known opioids.
The CFSRE recommends that forensic laboratories start utilizing previously developed non-targeted testing protocols or develop their own sensitive and up-to-date testing procedures for synthetic opioids. The agency also suggests prioritizing analytical testing of seized drug samples taken from drug overdose scenes, and sharing subsequent data with all relevant stakeholders.
Thus far, isotonitazene has been detected in the blood of people who died of overdoses in Illinois, Indiana and Tennessee. It was first detected in August 2019 in Belgium and Canada. The drug, which comes in a white/off-white powder form or pressed into counterfeit opioid pills, appears to be entering the United States from international avenues.
Photo credit: CFSRE