Current status of hair analysis on narcotics in Korea

Abstract

Since hair analysis of narcotics was first introduced to Korea in 1993, and it has been 30 years already. Although hair analysis in Korea started later than Europe or the United States, it has made remarkable progress in the field of forensic science. In this study, it was reviewed the current status of hair analysis on narcotics, mainly abused in Korea. In addition, the recent research trends also were investigated. Methamphetamine (MA) and cannabis, which are mainly abused narcotics in Korea, and other drugs such as ketamine (KT), synthetic cannabinoids (new psychoactive substances, NPS) and propofol were discussed here. The analytical methods for those drugs were developed by the National Forensic Service (NFS), mainly using gas chromatography-mass spectrometry (GC/MS) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). MA has been the most abused drug in Korea. Accordingly, its hair analysis was first introduced in 1993, earlier than any other drugs. In 2011, the NFS finally developed certified reference material (CRM) using Korean MA abusers’ hair. This achievement brought not only financial benefit as saving the cost of purchasing expensive standard products and it also contributed to the development of forensic science by providing free distribution to developing Asian countries. In addition, analytical method of cannabis in hair by gas chromatography-tandem mass spectrometry (GC-MS/MS) was also developed in 2011. It detects carboxytetrahydrocannabinol (THC-COOH), a metabolite of tetrahydrocannabinol (THC), following two steps using LC-MS system in two different acquisition modes (i.e., MRM and MS3). With using the method, it was found that both LOD and LOQ were 0.0001 ng/mg. After KT began to be regulated in Korea in 2005, the detection rates of KT in seized materials and urine during 2017–2020 were found 2.3 and 1.4%, respectively. Majority abusers of KT were young people in twenties. As a result of analyzing the hairs of 61 abusers, it was clear that KT was abused with other drugs such as methylenedioxymethamphetamine (MDMA) or MA rather than single administration. Since JWH-018 was first detected in Korea in 2009, the number of NPS has been rapidly increased also causing another a serious social problem. The most abused NPS is synthetic cannabinoids, accounting for 74% of the total. ABCHMINACA was the most detected synthetic cannabinoid in the hair of abusers from 2014 to May 2021. In February 2011, Korea designated propofol as a controlled drug and it was only country regulating it in the world. The detection method of the propofol in hair was finally established after two years later, 2013. For detection of the propofol in hair samples, LC-MS/MS is using to confirm propofol-glucuronide, major metabolite of the propofol. Though there is a cut-off value for each drug in hair recommended by the Society of Hair Testing (SoHT), each country has varied values due to the different analytical conditions such as method, equipment, and even cultural characteristics. Korea has been its own analytical method by referring to these international guidelines. The NFS is continuously developing new analytical method such as simultaneous analysis with increasing the number of abusers and drugs. Recently, research on hair metabolomics using animal is being actively conducted. One of findings was metabolic alterations in hair could provide insight into metabolic perturbation over a longer period than other conventional biological samples (i.e., plasma, urine). Thus, analytical techniques in hair metabolomics can be a significant approach with high potency for evaluating the animal and human pathological conditions.