Caffeine is the most widely consumed psychoactive agent worldwide and has the potential for abuse, but studies monitoring caffeine abuse in China are scarce. This study aims to estimate the prevalence of caffeine abuse in northwest China and investigate the correlation between caffeine and other drugs in hair and nails using an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Fingernail clippings were collected from 376 participants in northwest China to detect caffeine and 13 other illicit psychoactive drugs and their metabolites. Paired hair and nail samples were collected from 39 participants to investigate the correlation between caffeine and other drugs in hair and nails. The samples were decontaminated, pulverized, and extracted by a high-throughput nail sample preparation method and analyzed by UPLC-MS/MS. The results showed a risk of caffeine abuse in northwest China, with concentrations ranging from 0.43 to 10.6 ng/mg for healthy volunteers, 0.49-246 ng/mg for caffeine abusers, and 0.25-363 ng/mg for drug addicts in community rehabilitation centers. Caffeine was detected together with other illicit psychoactive drugs and their metabolites. Furthermore, positive detection correlations were found between hair and nail samples. This study provides a current perspective on caffeine abuse in northwest China and demonstrates the practical use of UPLC-MS/MS for the simultaneous detection of caffeine and 13 illicit psychoactive drugs and their metabolites in hair and nails. The results highlight the potential of nails as a supplementary matrix when hair samples are unavailable and emphasize the need for handling caffeine carefully given its potential for abuse.

In decomposed or skeletonized bodies, conventional matrices used in forensic toxicology may no longer be available for analysis. The aim of this paper was to test the survival and detection of toxicological substances in dry bone samples with over 23 years of post-mortem interval. In this perspective, bone samples from the cranium, ribs, and vertebrae of seven skeletons from the CAL Milano Cemetery Skeletal Collection, buried for over 23 years, fully decomposed and altered by taphonomic factors were selected based on their ante-mortem data, which included verified or suspected drug addictions or overdose. Qualitative and quantitative analyses were performed with Dionex™ ASE™ 350 Accelerated Solvent Extractor and Q-Exactive Orbitrap-mass spectrometry with a HPLC system. Positive results were obtained in six of the seven cases, and different psychoactive drugs (and in some cases their active metabolites) were detected, including analgesic (two opioids: methadone and buprenorphine) and anxiolytic drugs (benzodiazepines, in particular delorazepam, diazepam, nordiazepam, and lorazepam), a cannabinoid metabolite (THCCOOH) as well as metabolites of stimulants (benzoylecgonine and MDA). Consequently, this research shows that toxicological substances may be found in bone tissue after over 23 years of post-mortem interval.

Anabolic androgenic steroids (AAS) have been the most commonly abused substances taken by not only professional sportsmen but also recreational bodybuilders. The detection of micro-dose testosterone (T) misuse is particularly challenging as it possesses pseudo-endogenous origin and is sometimes impossible to be identified in urine samples. Dried blood (DB) obtained by finger pricking has been proven to be an alternative matrix for better correlating to physiological responses. Moreover, the introduction of the volumetric absorptive microsampling (VAMS) technology allows overcoming some major limitations of spotting blood onto a filter paper card. In this work, a fast and sensitive GC-MS/MS method was developed and validated for the quantification of AAS in DB collected by means of VAMS. T and the eight top abused synthetic AAS, namely nandrolone, boldenone, mesterolone, drostanolone, metenolone, metandienone, oxandrolone, and dehydrochloromethyl T were selected as the target analytes. The method based on VAMS exhibited good precision, accuracy as well as stability, and superior extraction recoveries over the punched DB spots reported in the literature. The chromatographic separation was achieved within 6.4 min and the detection limit is as little as 50 fg (i.e. able to detect 0.10 ng mL-1 in 20 μL of DB). Confirmed by forty real blood samples, the Deming regression and Bland-Altman analysis revealed that the VAMS DB could be employed for quantifying blood T level in agreement with using the serum specimen. The feasibility of the method was then successfully proven by the analysis of samples collected from a three-arm T administration trial. Our results highlighted that DB total T was a sensitive indicator for identifying transdermal micro-dosing of T. In the groups of receiving T gel administration, T concentrations could rise up to ten times higher than the baseline at 9 h after the application. As a future step, this approach is being expanded to a large cohort screening of bodybuilders at gym and ultimately may allow universal applications on monitoring sports drug misuse.