This Week’s Focus: Semi-Synthetic Cannabinoids
(Delta-8 & Delta-10)

The legalization of hemp-derived products in 2018 has led to the emergence of ∆9-tetrahydrocannabinol (∆9-THC) analogs and isomers. These substances are sold in shops and online as a legal alternative to cannabis with minimal regulatory oversight. The Food and Drug Administration and poison centers throughout the US have received numerous reports of semi-synthetic cannabinoid-associated adverse events in patients. Semi-synthetic cannabinoids are sold as smokable, vaping, and ingestible products. ∆8-Tetrahydrocannabinol is the most common isomer of ∆9-THC; and others include ∆10-tetrahydrocannabinol (∆10-THC) and hexahydrocannabinol (HHC).

This week, the Briefing highlights some recent literature on these products as well as our biospatial report on semi-synthetic cannabinoid-related 911 encounters. We will continue to monitor the consequences of use of these drugs. If you have any suggestions, results from your own data collection, or insights on the effects of these substances, let us know. And as always, if you have any ideas for the focus of our future briefings, please reach out.

The NDEWS team is preparing for our annual meeting—the College on Problems of Drug Dependence—which is being held in New Orleans June 14th to 18th with additional talks on the 19th and 20th for those attending the Research Society on Alcohol taking place from the 21st to the 25th of June, also in New Orleans. We look forward to sharing our work with you all in next Friday’s Briefing as well as select presentation findings from attendees.

Out of 4,746 EMS encounters for delta-8/delta-10-related overdoses from January 2023 to May 2025, 26 (0.5%) occurred in western states, 1,417 (29.9%) in central states and 3,303 (69.6%) in eastern states. The data shows a statistically significant decrease in delta-8/delta-10-related EMS encounters across Eastern and central states, and nationally overall.

To view the entire Special Report from our Weekly Briefing, click here.
Click here to learn more about NDEWS Hotspot Alerts

A study published in the International Journal of Drug Policy by Harlow, et al. experimented with the effects of hypothetical cannabis warning labels on perception of delta-8-THC gummies and vape products. A mixed within-between-subject experiment was embedded into a 2023 survey of 3,647 Southern California adolescents. Participants exposed to delta-8-THC gummies or vapes with prominent warning labels anticipated greater intoxication and perceived higher health risks compared to a control group. Effects were stronger for gummies (vs. vapes) and among cannabis-naïve youth suggesting that warning label design may affect product risk perceptions among adolescents.
Read the study here.

A recently published study in American Journal of Preventive Medicine by Patrick, et al. examined the prevalence and correlates of delta-8-THC (Δ8-tetrahydrocannabinol) use among young adults in the United States. Using national survey data from a 2023 Monitoring the Future (MTF) follow-up of 2,450 12th-grade students, the authors found that 12.4% reported past-year use of delta-8-THC. Use was significantly less common in the West compared to the South and Midwest and was lower in states with delta-8-THC regulations or with legalized recreational cannabis.
Read the study here.

A recently published analysis in Journal of Analytical Toxicology by Ballotari et al. featuring NDEWS Co-Investigator and Sentinel Site Director Dr. Bruce Goldberger, optimized a method to detect cannabinoids in breastmilk using liquid chromatography–tandem mass spectrometry (LC-MS/MS). Researchers analyzed 57 breastmilk samples collected across two postpartum time points. The optimized assay detected Δ9-THC in 33.3% of samples, cannabigerol (CBG) in 12.2%, cannabidiol (CBD) in 5.3%, and Δ8-THC in 1.8%.
Read the study here.

A recently published case series in Cureus by Singh et al. highlights psychiatric manifestations observed in three patients with distinct preexisting psychiatric disorders who developed various symptoms, including psychosis, after consuming legally obtained delta-8-THC products. The authors emphasize the need for increased awareness of potential psychiatric risks associated with delta-8-THC, particularly among individuals with underlying psychiatric disorders, and highlight the critical lack of clinical research on these increasingly accessible products.
Read the case series here.

A recently published study in Drug and Alcohol Dependence by Spindle et al. evaluated the acute effects of inhaled delta-8-THC and delta-9-THC in a controlled, double-blind, within-subject crossover trial of 20 healthy adults with no cannabis use in the past month. Across five randomized outpatient sessions, researchers assessed subjective effects, cognitive and psychomotor performance (via DRUID app), puff topography, vital signs, and blood cannabinoid levels. Both cannabinoids produced subjective effects relative to placebo, but 20 mg delta-9-THC elicited stronger ratings of “drug effect” and “unpleasant” feelings than 10 mg delta-8-THC. Delta-9-THC also significantly impaired psychomotor performance and prompted compensatory puffing behavior, with distinct blood metabolite profiles observed between the two compounds.
Read the study here.

A recent publication in Cannabis and Cannabinoid Research by Johnson et al. analyzed the cannabinoid content of 56 selected cannabidiol (CBD) gummy products. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to measure the concentration of CBD, accuracy of the product labeling regarding CBD concentration, and concentration of delta-9-THC and other cannabinoids of interest in each product. Researchers found that products contained a mean of 21.38 (±11.16) mg CBD per gummy (range: 5.70 − 59.99 mg) and that 70% of the products contained CBD in a concentration that differed by 10% of the dose listed on the packaging. Additionally, 39% of the products contained delta-9-THC and 5% contained delta-8-THC.
Read the study here.

A recent publication in Drug Testing and Analysis by Dadiotis et al. investigated the chemical consistency of semisynthetic (SSC) and synthetic cannabinoids with the commercial names “CB9”, “CBX”, and “tresconol” and their potential origin. Through nuclear magnetic resonance (NMR), gas chromatography-mass spectrometry (GS-MS), and high-resolution mass spectrometry (HRMS), three SSCs were identified in commercially available products with limited pharmacological and toxicological data: [2-(E)-propen-1-yl]-Δ8-tetrahydrocannabinol-acetate in “CB9”, [2-propen-2-yl]-Δ9-tetrahydrocannabinol in “tresconol” and [2-propen-2-yl]-Δ8-tetrahydrocannabinol in “CBx”. The authors emphasized the need for regulatory authorities to prioritize the monitoring and control of SSCs to mitigate health risks.
Read the study here.

A recent publication in Drug Testing and Analysis by Hundertmark et al. focused on the emergence of semi-synthetic cannabinoids (SSC) in the European drug market. The study analyzed the composition and prevalence of SSCs, particularly hexahydrocannabinol (HHC) and its derivatives, such as delta-8-THC, in various seized products. Delta-8-THC was detected in 90% of the samples tested.
Read the study here.

Recent reports from Cayman Chemical and the European Union Drugs Agency (EUDA) highlight semi-synthetic cannabinoids (SSCs). In Cayman Chemical’s NPS Snapshot, information on novel psychoactive substances (NPS) derived from natural components found in the Cannabis sativa L. plant, such as delta-8-THC and delta-10-THC are discussed. In EUDA’s 2025 European Drug Report, 24 SSCs were identified in drug markets across Europe by the end of 2024.

Full Reports:
- NPS Snapshot: Semi-Synthetic Cannabinoids
- European Drug Report 2025: New psychoactive substances – the current situation in Europe

You are invited to attend the NDEWS Summit at the College on Problems of Drug Dependence (CPDD) 87th Annual Scientific Meeting on Saturday, June 14th (06/14/2025) from 4:00 pm - 6:00 pm CT in Bayside Ballroom AB, 4th floor. The Summit will be open to all CPDD meeting attendees. 

We hope to see you there!

NDEWS Posters and Presentations at CPDD

In June, the NDEWS team will be traveling to attend the 87th College on Problems of Drug Dependence (CPDD) Annual Meeting in New Orleans, Louisiana. Along with posters, the NDEWS team will be presenting a late-breaking abstract, an oral presentation and two invited symposia. We invite you to join us for these presentations. Please find the presentation information below:

Sunday, June 15
3:30 pm - 4:45 pm CT Late-Breaking Abstract
Anesthetics (“-Caines”) Adulterate the Illicit Fentanyl Supply: A National Drug Early Warning System (NDEWS) Alert
Joseph Palamar, Joshua DeBord, Alex Krotulski, Bruce Goldberger

5:00 pm - 6:30 pm CT Poster Session 1 (Napoleon Ballroom CD, 3rd Floor)
Trends in Nonfatal Fentanyl Poisonings Involving Stimulants in the United States, 2015–2023
Nicole Fitzgerald, Joshua Black, Linda Cottler, Silvia Martins, Joseph Palamar

Monday, June 16
10:45 am - 12:15 pm CT Invited Symposium
Found in Translation: Coordinated Preclinical, Human Laboratory and Epidemiological Approaches to Understanding Polydrug Use
William Stoops, Lori Knackstedt, Linda Cottler, Christa Corley

3:30 pm - 4:30 pm CT Oral Session: Sex Matters: Translational Evaluations of Sex-Specific Factors in Substance Use
Sex Differences in Problematic Substance Use, Mental Health, and Social Determinants of Health among Middle-Aged and Older Adults in the All of Us Research Program
Vijaya Seegulam, Bia Whipp, Liva LaMontagne, Linda Cottler

5:45 pm - 7:15 pm Poster Session 2 (Napoleon Ballroom CD, 3rd Floor)
Natural Language Processing Analysis of 7-Hydroxymitragynine Reddit Discussion
Daniel Van Zant, Kirsten Smith, Oliver Grundmann, Catherine Striley, Elan Barenholtz, Christopher McCurdy, Linda Cottler

Tuesday, June 17
3:45 pm- 4:45 pm CT Oral Presentation at Mini Symposium: Prevalence and Characteristics of Recreational Ketamine Use among Nightclub Attendees and College Students in the New York Tristate Area.
The Current Landscape of Medical and Recreational Ketamine Use
Shahar Almog, Meredith Berry, Joseph Palamar 

5:30 pm - 7:00 pm CT Poster Session 3 (Napoleon Ballroom CD, 3rd Floor)
Reported Use of Recreational and Medical Cannabis, Delta-8, and Delta-10: Findings from NDEWS Sentinel Sites and Hotspots (2022–2023)
Tamara Millay, Vijaya Seegulam, Monica Bhargavi Kodali, Linda Cottler

Wednesday, June 18
2:00 pm - 3:30 pm CT Poster Session 4 (Napoleon Ballroom CD, 3rd Floor)
Alcohol Polysubstance Use among past 30-Day Opioid Users in Northern Florida: A Model for Back Translational Research
Christian Conger, Linda Cottler

Friday, June 20
3:00 pm - 5:00 pm CT Polysubstance Use: From Bench to Communities Session 2 Keynote (LSU Health Sciences Center, 411 S Prieur Street, New Orleans, LA 70112)
The National Drug Early Warning System Networks, Initiatives and Data: How can we help?
Linda Cottler

📅 Date: Friday, June 20, 2025

🕑 Time: 3:00 pm - 5:00 pm CT

📍 Location: New Orleans

Learn more here.

📅 Date: Thursday, June 26, 2025

🕑 Time: 1:30 pm ET

📍Location: Online

Learn more here.

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If you miss or want to learn more about NDEWS Original Content, you can find our archived content on the NDEWS website:

     • NDEWS Hotspot Alerts using substance-related EMS data
     • NDEWS Rapid Street Reporting (RSR) survey data reports
     • NDEWS Web Monitoring Team Reddit Alerts
     • NDEWS Sentinel Site Reports
     • Previous issues of the NDEWS Weekly Briefings

The Weekly Briefing is a newsletter published each week by the National Drug Early Warning System (NDEWS) Coordinating Center, which is funded by the National Institute on Drug Abuse (U01DA051126) to the University of Florida (MPI: Cottler (contact), Co-Is: Goldberger, Nixon, Striley), NYU Langone Health (MPI: Palamar), and Florida Atlantic University (Co-I: Barenholtz). Any item may be reproduced provided the source is acknowledged.