Half of Low-THC Cannabis Products in Switzerland Were Laced with Synthetic Cannabinoids

Drug checking services found 50% of low-THC cannabis samples submitted in Switzerland were adulterated with synthetic cannabinoids, with users of adulterated products reporting significantly more adverse effects.

Monti, Manuela Carla et al.·Drug testing and analysis·2022·Moderate EvidenceCross-Sectional
RTHC-04076Cross SectionalModerate Evidence2022RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Cross-Sectional
Evidence
Moderate Evidence
Sample
N=94

What This Study Found

Of 94 samples, 50% contained up to three different synthetic cannabinoids, with MDMB-4en-PINACA most common. All adulterated flowers had 1% or less THC. The synthetic cannabinoid group had significantly more adverse events (P=0.041), with worse psychological (P=0.0007) and cardiological (P=0.020) outcomes compared to the THC-only group.

Key Numbers

94 samples; 50% adulterated; up to 3 SCs per sample; MDMB-4en-PINACA most common; all adulterated flowers had ≤1% THC; more psychological (P=0.0007) and cardiac (P=0.020) adverse effects

How They Did This

Analysis of cannabis samples submitted to three Swiss drug checking services from January 2020 to July 2021. LC-HRMS for synthetic cannabinoid screening and semi-quantification; GC-FID for THC/CBD quantification. User self-reports of adverse effects collected.

Why This Research Matters

Legal low-THC cannabis products are being used as carrier materials for dangerous synthetic cannabinoids. Users think they are consuming a mild product but are unknowingly exposed to highly potent substances.

The Bigger Picture

This represents a new public health threat: legal low-THC cannabis products being weaponized as vehicles for synthetic cannabinoids. Drug checking services proved essential for detecting this trend.

What This Study Doesn't Tell Us

Samples submitted to drug checking services may not represent the broader market. Adverse effect reporting was voluntary and self-reported.

Questions This Raises

  • ?Is this adulteration trend spreading beyond Switzerland?
  • ?Would mandatory testing of legal low-THC products prevent this contamination?

Trust & Context

Key Stat:
50% of low-THC samples contained synthetic cannabinoids
Evidence Grade:
Systematic drug checking with validated analytical methods and user-reported outcomes, though samples are self-selected.
Study Age:
Published in 2022
Original Title:
Adulteration of low-delta-9-tetrahydrocannabinol products with synthetic cannabinoids: Results from drug checking services.
Published In:
Drug testing and analysis, 14(6), 1026-1039 (2022)
Database ID:
RTHC-04076

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / ObservationalSnapshot without intervening
This study
Case Report / Animal Study

A snapshot of a population at one point in time.

What do these levels mean? →

Frequently Asked Questions

Can legal low-THC cannabis contain dangerous additives?

This Swiss study found 50% of low-THC cannabis samples were adulterated with synthetic cannabinoids, with some containing up to three different synthetic compounds. Users cannot detect these by appearance or smell.

What happens when you unknowingly consume synthetic cannabinoids?

Users of adulterated products reported significantly more adverse effects, particularly psychological problems (P=0.0007) and cardiac symptoms (P=0.020) compared to those who consumed genuine low-THC cannabis.

Read More on RethinkTHC

Cite This Study

RTHC-04076·https://rethinkthc.com/research/RTHC-04076

APA

Monti, Manuela Carla; Zeugin, Jill; Koch, Konrad; Milenkovic, Natasa; Scheurer, Eva; Mercer-Chalmers-Bender, Katja. (2022). Adulteration of low-delta-9-tetrahydrocannabinol products with synthetic cannabinoids: Results from drug checking services.. Drug testing and analysis, 14(6), 1026-1039. https://doi.org/10.1002/dta.3220

MLA

Monti, Manuela Carla, et al. "Adulteration of low-delta-9-tetrahydrocannabinol products with synthetic cannabinoids: Results from drug checking services.." Drug testing and analysis, 2022. https://doi.org/10.1002/dta.3220

RethinkTHC

RethinkTHC Research Database. "Adulteration of low-delta-9-tetrahydrocannabinol products wi..." RTHC-04076. Retrieved from https://rethinkthc.com/research/monti-2022-adulteration-of-lowdelta9tetrahydrocannabinol-products

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.