The biomarker and the study
A team led by Andrea Steuer at the university’s Institute of Forensic Medicine had in 2021 helped discover a "promising biomarker" for the drug — a compound of GHB and a sugar thought to be ribose, known as GHB-pentose.
"Unlike GHB itself, this biomarker remains detectable in the urine for longer after intake," the statement said.
The study indicated that the compound "remained detectable for up to three days after GHB intake, representing the longest detection window reported for a direct GHB-related biomarker to date".
For their study published last week in the peer-reviewed scientific journal Drug Testing and Analysis, the researchers analysed 2,414 anonymised urine samples from genuine forensic cases since 2024.
Highlighting 14 samples, the researchers found that "although GHB levels measured were below the threshold set for the test, GHB-pentose was still detected".
"In eight of these 14 cases, the case details supported the suspicion that GHB had been taken or administered previously," the statement said.
Those cases included three suspected criminal offences — two robberies and one alleged sexual assault, in which urine samples were only gathered 13-16 hours after the incident.
"The findings offer the first indication from forensic practice that GHB-pentose remains detectable beyond the usual detection window for GHB," Dr Steuer said in the statement.