Determination of Drugs of Abuse in Hair by LC-MS-MS: Application to Suicide Attempts Investigation

Abstract

Considering that the use of psychoactive substances (PSs) is a risk factor to either higher intensity or frequency of suicidal behavior, hair analysis was conducted to investigate the most consumed PSs (opiates, amphetamine stimulants, marijuana, cocaine and heroin) in patients who attempted suicide and received urgent care at emergency service. Hair samples were extracted using methanol and sonicated under heating and then analyzed using liquid chromatography-tandem mass spectrometry. During validation, the method complied with international recommended criteria, with limits of detection between 0.0025 and 0.05 ng/mg and linearity between 0.1 and 4 ng/mg for methamphetamine, 3,4-methylenedioxymethamphetamine (MDMA), morphine, amphetamine, 6-acetylmorphine, 3,4-methylenedioxyamphetamine (MDA), fenproporex, diethylpropion and codeine; between 0.025 and 1 ng/mg for tetrahydrocannabinol (THC), benzoylecgonine and cocaethylene and between 0.25 and 10 ng/mg for cocaine and mazindol. A total of 109 hair samples were analyzed and segmented in 404 parts. Among all analyzed samples, 30.3% were positive for at least one PS (n = 33), such as cocaine (90.9%), codeine (12.1%), morphine (3.0%), MDMA (3.0%) and THC (3.0%). In segmental analysis of cocaine positive samples (n = 30), 76.7% of the samples indicated recent exposure to cocaine (<1 month). This same behavior was observed when analyzing codeine (n = 4) and morphine (n = 1). THC positive samples indicated exposure dated ∼4 months prior. In conclusion, the method was validated following international recommendations for the 12 most consumed PSs in Brazil, as well as two of the most common found metabolites.