Poster apresentado no 60th Annual TIAFT meeting of the International Association of Forensic Toxicologists, Rome ( Italy), 2023Background and aim: Marijuana, hashish and other psychoactive products obtained from Cannabis are the most produced and trafficked illicit drugs around the world.
Methods: The authors studied all the positive cases for cannabinoids in the Centre of Portugal; from autopsies at the Forensic Clinical and Pathology Service of Coimbra’s Delegation of the National Institute of Legal Medicine and Forensic Sciences (NILMFS), from other autopsies in the Centre of Portugal, and road traffic and labour accidents from June 2020 until March 2023. Results were from blood samples routinely tested for the presence of cannabinoids by enzyme immunoassay (ELISA) and confirmed by LC-MS/MS. When requested, other substances were analysed.
Results and discussion: During the study period, a total of 4599 toxicological requests for cannabinoids were received at the Forensic Toxicology Laboratory. 461 cases (10.0%) tested positive in screening tests, all confirmed by LC-MS/MS. Among positive cases, 77% were road traffic surveillance cases , and 24.9% related to other antemortem and postmortem cases.We observed that there was an accentuated consumption of cannabinoids between ages 21 and 30 years old, average age 33 years, and a higher prevalence in men (92.4%). THC was confirmed and quantified in 76.5% of the cases, with an average blood concentration of 13.5 ng/mL; the mean and percent for the active metabolites, 11-OH-THC, was 5.9 ng/mL in 44.5% and for THCCOOH was 20.1 ng/mL in 56.2% of the positive cases. It is important to highlight that in the 75.1% positive road traffic surveillance cases the achieved THC average was 11.6 ng/mL and in postmortem cases related to road traffic accidents this value increased to 16.0 ng/mL. 25.4% of the cases (n=117) had cannabinoids together with other psychoactive substances and ethanol was present in 162 of the cases, with 33.9% presenting a BAC ≥0.5 <1.2 g/L and 50.6% a BAC ≥1.2 g/L. 20.9% of the Forensic Pathology and Clinic cases were road accidents with 79.2% drivers.
Conclusion: Cannabis is frequently used before and during driving with high concentrations of the active compounds demonstrating impairment increasing theof a crash. It is also important to be aware of the results showing simultaneous use of THC and alcohol increasing accident risk.N/
