In September, three of Axis’ toxicologists presented at the 2026 combined annual meetings of the Society of Forensic Toxicologists (SOFT) and The International Association of Forensic Toxicology (TIAFT) in Chicago, Illonois.  Axis is fortunate to be able to share important developments with others in the field including our valued clients. The following is a summary of those presentations.  Please contact our toxicologists with any questions about the presentations or assistance with interpretation via email at [email protected] or telephone at 317-759-4869 option 3. 

Novel (Re)Emerging Substance? 5F-ADB Detection in Postmortem Toxicology

Kevin Shanks gave an oral platform presentation regarding the re-emerged synthetic cannabinoid, 5F-ADB and its detection in postmortem toxicology casework. 5F-ADB, an older synthetic cannabinoid, first detected in the USA in 2014-2015 and controlled by the US Federal government in 2016, has reappeared on the illicit drug market after a multi-year disappearance. Because of this disappearance from the drug market, Axis removed 5F-ADB from its synthetic cannabinoid testing in 2022, but it was added back to the scope of testing in 2025 when it re-emerged in the illicit drug supply and in postmortem toxicology casework in the USA.

During 10/1/2025-03/31/2026, the laboratory detected 5F-ADB butanoic acid metabolite in 40 postmortem toxicology cases across 10 states (California, Florida, Indiana, Kentucky, Michigan, Missouri, Nebraska, Ohio, South Dakota, and West Virginia). Sixteen of the 40 decedents were inmates in prisons or correctional facilities. 5F-ADB metabolite was detected as the only substance in a single case. Excluding caffeine, cotinine, naloxone, and amiodarone, the metabolite was detected as the sole substance in 12 fatalities. The synthetic cannabinoid MDMB-4en-PINACA was detected as its butanoic acid metabolite in 10 of the cases, while ethanol and methamphetamine were each observed in 4 cases. The presentation concluded with a reminder that while most novel substances emerge and then disappear rapidly from the market, some do persist for months and years. Rarely, a substance will disappear completely and then re-emerge years later as a drug of interest.

Fentanyl and Beyond: Detection, Interpretation, and Emerging Threats in the Evolving Synthetic Opioid Landscape 

Stuart Kurtz presented at a workshop discussing the rise and fall and rise again of carfentanil and the lessons Axis learned from that event. The workshop was put on by the SOFT NPS Committee to which Stuart was appointed in January 2026. 

Axis’ toxicologists have presented information about carfentanil in past blog posts, including some of the data presented during the workshop. During 2021 and 2022, Axis detected carfentanil in 11 cases which was significantly down from 108 cases in 2020. In 2023, a cluster of 10 cases was noted from May to July. Late in September 2023, carfentanil cases were noted by Axis and other labs in the state of Florida. Detections in October to December 2023 were primarily in Florida and Kentucky. 

Starting in 2024, carfentanil was detected in many other states that submit casework to Axis. Florida saw a sharp decrease in cases compared to late 2023. The top 4 states for detection in Axis cases from 2025 through July 2026 are Indiana, Kentucky, West Virginia, and Michigan. Carfentanil continues to be detected across different regions of the country. 

While carfentanil is most often detected with another opioid, such as fentanyl, there have been 11 cases out of 196 in 2025 through July 2026 where it was the only detected drug of interest. Cases will often present similar to other opioid overdoses. It is significantly more potent than fentanyl and concentrations in cases are often <0.5 ng/mL and can even be <0.1 ng/mL. Like other opioids, carfentanil does not have any visually distinct features to identify it without further testing. It can come as a white or off-white powder or be pressed into counterfeit pills. Further testing of evidence at the scene can help inform toxicology testing by identifying substances to which the person may have been exposed. 

BTMPS Update

Dr. Marinetti presented an updated version on BTMPS, (Bis[2,2,6,6-tetramethyl-4-piperidyl] sebacate), brand name Tinuvin®770.  For the history and background of BTMPS please refer to the two previous Axis blog posts on BTMPS – links are in the references below.  

As previously stated, Axis has identified four confirmed positive postmortem cases with BTMPS, two without the presence of illicit drugs, and two cases with the presence of illicit drugs.  The cases without illicit drugs were an oxycodone overdose with a high concentration of oxycodone, and an Adderall® overdose with a high concentration of amphetamine.  A third case was an antemortem case involving an individual that was subject to urine testing due to pain management therapy.  The urine test results matched the prescriptions the individual was taking with no illicit drugs present, and he was therefore considered compliant.  However, BTMPS was also detected in the urine sample.  This last case is the most concerning because his doctor wanted to suspend him from the pain management program.

It was discussed at the SOFT/TIAFT meeting about how the BTMPS entered the licit drug supply.  It is possible that the BTMPS was a contaminant on the oxycodone or the amphetamine pills from the plastic medication bottle(s) in which they were stored since manufacture, or from an ingredient used to manufacture the pills, and because so many of them were ingested at one time, the BTMPS accumulated to a detectable concentration. For the individual in pain management therapy, he was on multiple medications, including hydrocodone, most of which were stored in plastic bottles. 

The University of Washington drug detection data was updated and still shows that in licit drug samples, BTMPS was detected.  In 324 prescription opioid samples (excluding fentanyl), 3.4% were positive for BTMPS, thus supporting the BTMPS leaching out of the plastic containers during pill storage or manufacture.  In addition, out of 163 samples sold as M30s (prescription oxycodone), 3.7% were positive for BTMPS.  

Further evidence that the BTMPS may be leaching out of plastic was found. BTMPS is a potent calcium channel blocker and nicotine receptor antagonist.  For this reason, it has been used in nicotinic receptor studies.  It was discovered by Papke et.al, that in the control and the BTMPS treated nicotinic receptors; both produced the same results of receptor blockade. After investigation it was discovered that BTMPS was leaching out of the plastic syringes that were being used.  When the plastic syringes were removed from use, the control and BTMPS groups no longer produced the same results.  

Because BTMPS has been found in biological specimens from postmortem and antemortem samples without the presence of illicit drugs, in prescription opioid pills, and found to leach out of plastic syringes, there can be no assumption that the individual used illicit drugs if BTMPS is confirmed.  In addition, through questions and comments after the presentation, some clinical labs have stopped testing for BTMPS because of its detection in samples without illicit drugs leading to the possibility of incorrect results interpretation. 

References for BTMPS

• Glossman H., Hering, S., Savchenko, A., Berger, W., et.al., A light stabilizer (Tinuvin 770) that elutes from polypropylene plastic tubes is a potent L-type Ca2+-channel blocker.  Proc. Natl. Acad. Sci. USA, Vol. 90, pp9523-9527, October 1993.  
• Papke, R.L., Craig, A.G., and Heinemann, S.F., Inhibition of nicotinic acetylcholine receptors by bis (2,2,6,6-tetramethyl-4-piperidinyl) sebacate (Tinuvin 770), an additive to medical plastics.  J.Pharmacol Exp Ther. 1994 Feb;268(2):718-26. 
• UV Stabilizer BTMPS in the Illicit Fentanyl Supply in 9 US Locations, Letter, Journal of the American Medical Association, February 5, 2025. 
• Where do we see BTMPS? Addictions, Drug and Alcohol Institute, University of Washington, https://adai.washington.edu/WAdata/DrugChecking/BTMPS.html, 2026. 
• First two BTMPS Blog posts on the Axis Website, Feb 6, 2026 https://axisfortox.com/drug-primer-btmps/ and June 2, 2026 https://axisfortox.com/matt-2026-recap-btmps/