Public health officials depend on drug prevalence data to address the risks and impacts of substance use within communities. By tracking trends in drug use, authorities can identify emerging threats, develop early interventions, and refine treatment strategies. Since 2013, increased law enforcement drug seizures and a rise in court-ordered mandatory drug testing have contributed to a large database for studying these patterns, particularly as opioid-related overdoses rise due to potent substances like fentanyl.

Traditionally, forensic toxicologists rely on urine or oral fluid samples for court-ordered drug tests, which only detect recent drug use. In contrast, hair testing can identify use over a much longer period, up to several months, although it rarely screens for fentanyl. To better understand fentanyl use among those under mandatory testing, researchers Megan Grabenauer and Nichole Bynum undertook a detailed study involving the detection of fentanyl in hair samples, comparing court-mandated results with the general workforce and conducting a six-year retrospective analysis.

Fentanyl Prevalence in Hair Samples

The researchers tested 520 hair samples collected through court-ordered drug tests over six months, using mass spectrometry to analyse for fentanyl and its related compounds. They observed a positivity rate of 54%, with methamphetamine detected most frequently (27%) followed by oxycodone (15%). Fentanyl alone appeared in 15% of samples, and the prevalence of “fentanyl alone” (without other drugs) was 2.9%. These cases would have been missed in standard testing, as current protocols don’t routinely include fentanyl or its analogs.

Interestingly, samples from individuals with artificially coloured hair had a much higher drug positivity rate (74%) compared to natural hair samples. However, hair length and curl type did not significantly impact results.

Six-Year Retrospective Analysis

To identify broader drug use trends, the team examined data from a six-year period, comparing court-ordered test results to those from the general workforce. The results showed that people under mandatory testing had a positivity rate of 34% for oral fluid tests and 56% for hair tests, substantially higher than the general workforce positivity rates (10.0% for oral fluid and 10.4% for hair).

Differences in Drug Detection Between Oral Fluid and Hair Tests

The researchers found varying results between oral fluid and hair tests, which indicated different patterns of drug use. In oral fluid samples, the most common drugs were THC (64%), amphetamines (26%), buprenorphine (15%), cocaine (7%), and fentanyl (6%). In hair samples, the leading substances were amphetamines (59%), cocaine (30%), THC (28%), opioids (27%), and benzodiazepines (3%). By analysing these results across different court types, they noted that family court cases produced the highest proportion of positive tests, with oral fluid results showing higher positivity than hair for certain cases.

Policy Implications

According to Grabenauer, “This project offers actionable data across multiple U.S. jurisdictions, representing the first large-scale study on drug prevalence in a court-ordered testing population. It provides insight into the combinations of drugs commonly found in these cases, especially fentanyl with other substances.”

The findings from this study, funded by the National Institute of Justice (NIJ), could influence policies in various ways, including:

• Acting as an early indicator of shifting drug trends.
• Informing public safety and health agencies with contextual data for other drug use metrics.
• Providing policymakers with data to consider updates in testing protocols, including the inclusion of fentanyl screening.
• Advancing the use of hair testing to detect fentanyl and related compounds.

This research highlights the growing importance of comprehensive testing protocols in monitoring drug use patterns and responding to the ongoing opioid crisis.

References

National Institute of Justice, “Detecting Fentanyl Use Through Court-Ordered Mandatory Drug Testing,” September 26, 2024, nij.ojp.gov: 

https://nij.ojp.gov/topics/articles/detecting-fentanyl-use-through-court-ordered-mandatory-drug-testing