Simultaneous determination of synthetic cannabinoids and their metabolites in human hair using LC-MS/MS and application to human hair.

Hair is one of the key samples for judging drug abuse in the field of forensic science. However, few studies have examined synthetic cannabinoids and their metabolites in human hair. Synthetic cannabinoids are a class of chemicals that bind to cannabinoid receptors, but they differ structurally from the cannabinoids found in cannabis. They have been sold sprayed on dried, shredded plant material under brand names such as "Spice" since the 2000s. In South Korea, synthetic cannabinoids have been widely distributed since 2009 and many types detected up to now. Unlike traditional drugs such as methamphetamine and cannabis, the abuse trends of synthetic cannabinoids were variable by regions and changed according to the times. If new types of synthetic cannabinoids become popular which has been altered in some structures, it becomes difficult to identify using exist analytical method. Therefore, it is important to develop a new analytical method for synthetic cannabinoids currently being abused in society. In this study, we developed simultaneous analytical methods for the detection of 18 synthetic cannabinoids and 41 of their metabolites in authentic human hair samples using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Selectivity, linearity, limits of detection (LODs), limits of quantification (LOQs), precision, accuracy, matrix effect, recovery, and process efficiency were evaluated, and all results were acceptable. Additionally, the distribution of synthetic cannabinoids in the head hair of Korean drug abusers from 2016 to 2018 was investigated. Hair samples from 43 individuals suspected of synthetic cannabinoid use were provided by law enforcement agencies. The drugs detected most prevalently in the head hair of Korean drug abusers were AB-CHMINACA and JWH-210.