A new study in Frontiers in Toxicology highlights the urgent need to expand routine post-traffic accident testing to include novel drugs. It is the first comprehensive investigation into the contribution of a wide range of so-called “new psychoactive substances” to U.S. traffic accidents.
“Here, we show that new psychoactive substances (NPS), a class of drugs that has rapidly increased in prevalence over the last 15 years, play a role in traffic accidents,” said Dr. Roy Gerona, one of the study’s corresponding authors and an adjunct professor at the University of California, San Francisco.
NPS, colloquially known as “designer drugs,” “legal highs,” “herbal highs,” and “bath salts,” are drugs that do not fall under the United Nations Single Convention on Narcotic Drugs of 1961 or the Convention on Psychotropic Substances of 1971, but are classified by experts as harmful to health. Examples include designer benzodiazepines, synthetic cathinones and cannabinoids, piperazines, and tryptamines. The full spectrum of their effects on physical and mental health is still poorly understood; however, they can include agitation, psychosis, aggression, and addiction. NPS also contribute to the devastating opioid crisis in the U.S., as they can contaminate fentanyl supplies, leading to additive toxicity, or be sold by dealers in place of fentanyl.
Flying Under the Radar
Most existing urine drug tests do not target NPS, as these are typically only detectable by expensive high-resolution mass spectrometry (HRMS) in specialized laboratories.
Here, Gerona and colleagues examined the prevalence of NPS in the blood of traffic accident victims in Northern and Southern California between January and July 2024. They focused on the first 1,000 adult traffic accident victims who sought care at one of two representative trauma centers in Los Angeles and Sacramento during that period and from whom blood was drawn as part of routine emergency care.
Using HRMS, they confirmed the presence of NPS in the blood of 17 patients (2%). Among these, Bromazolam was the most common (seven patients), followed by para-fluorofentanyl (four patients) and mitragynine (three patients). Acetylfentanyl, N-methylnorfentanyl, protonitazene, etizolam, and xylazine were each detected only once.
“The NPS types found in our first 1,000 cases reflect the predominant NPS types identified in nationwide surveillance studies, with central nervous system depressants such as designer benzodiazepines and fentanyl analogs being the most common,” Gerona summarized.
A Mixed Picture
The results also showed that consumers frequently mix NPS with other drugs. All but two of the 17 patients with NPS in their blood had also tested positive for at least one traditional recreational drug. Nine had taken a sedating NPS along with a stimulant such as cocaine or methamphetamine, while eleven had combined NPS with traditional opioids. Another 273 (27%) patients tested positive for traditional recreational drugs, but not for NPS.
