Prevalence and concentrations of new designer stimulants, synthetic opioids, benzodiazepines, and hallucinogens in postmortem hair samples: A 13-year retrospective study

Validation and application of a method for the quantification of 137 drugs of abuse and new psychoactive substances in hair

INTRODUCTION

In the dynamic universe of new psychoactive substances (NPS), the identification of multiple and chemically diverse compounds remains a challenge for forensic laboratories. Since hair analysis represents a gold-standard to assess the prevalence of NPS, which are commonly detected together with classical drugs of abuse (DoA), our study aimed at developing a wide-screen method to detect and quantify 127 NPS and 15 DoA on hair.

MATERIALS AND METHODS

A multi-analyte ultra-high performance liquid chromatography mass spectrometry method for the identification and quantification of 127 NPS (phenethylamines, arylcyclohexylamines, synthetic opioids, tryptamines, synthetic cannabinoids, synthetic cathinones, designer benzodiazepines) and 15 DoA in hair samples was developed. A full validation was performed according to the European medicines Agency (EMA) guidelines, by assessing selectivity, linearity, accuracy, precision, limit of quantification (LOQ), limit of detection (LOD), matrix effect and recovery. As a proof of the applicability, the method was applied to 22 authentic hair samples collected for forensic purposes.

RESULTS

Successful validation was achieved, by meeting the required technical parameters, for 137 compounds (122 NPS and 15 DoA), with LOQ set at 4 pg/mg for 129 compounds, at 10 pg/mg for 6 and at 40 pg/mg for 2. The method was not considered validated for 5 NPS, as LLOQ resulted too high for a forensic analysis (80 pg/mg). Among authentic forensic samples, 17 tested positive for DoA, and 10 to NPS, most samples showing positivity for both. Detected NPS were ketamine and norketamine, 5-MMPA, ritalinic acid, methoxyacetyl fentanyl, methylone and RCS-4.

CONCLUSION

The present methodology represents an easy, low cost, wide-panel method for the quantification of 122 NPS and 15 DoA, for a total of 137 analytes, in hair samples. The method can be profitably applied by forensic laboratories. Similar multi-analyte methods on the hair matrix might be useful in the future to study the prevalence of NPS and the co-occurrence of NPS-DoA abuse.

Target and Nontarget Screening to Support Capacity Scaling for Substance Use Assessment through a Statewide Wastewater Surveillance Network in New York

Wastewater-based epidemiology (WBE) has been widely implemented around the world as a complementary tool to conventional surveillance techniques to inform and improve public health responses. Currently, wastewater surveillance programs in the U.S. are evaluating integrated approaches to address public health challenges across multiple domains, including substance abuse. In this work, we demonstrated the potential of online solid-phase extraction coupled with liquid chromatography-high-resolution mass spectrometry to support targeted quantification and nontargeted analysis of psychoactive and lifestyle substances as a step toward understanding the operational feasibility of a statewide wastewater surveillance program for substance use assessment in New York. Target screening confirmed 39 substances in influent samples collected from 10 wastewater treatment plants with varying sewershed characteristics and is anticipated to meet the throughput demands as the statewide program scales up to full capacity. Nontarget screening prioritized additional compounds for identification at three confidence levels, including psychoactive substances, such as opioid analgesics, phenethylamines, and cathinone derivatives. Consumption rates of 12 target substances detected in over 80% of wastewater samples were similar to those reported by previous U.S.-based WBE studies despite the uncertainty associated with back-calculations. For selected substances, the relative bias in consumption estimates was sensitive to variations in monitoring frequency, and factors beyond human excretion (e.g., as indicated by the parent-to-metabolite ratios) might also contribute to their prevalence at the sewershed scale. Overall, our study marks the initial phase of refining analytical workflows and data interpretation in preparation for the incorporation of substance use assessment into the statewide wastewater surveillance program in New York.

Are the NPS commonly used? An extensive investigation in Northern Italy based on hair analysis

New psychoactive substances (NPS) are present on the Italian illicit markets, but data from the analysis of biological samples to evaluate their real consumption are rare. For this reason, an epidemiological study was carried out by means of a ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS-MS) method for the determination of 115 NPS on the keratin matrix. A total of 847 hair samples were collected in 2020 and 2021 and analyzed. The sample donors were in the age range of 18-40 years, from both genders, and were tested either for driving relicensing or for drug withdrawal monitoring. The UPLC-MS-MS system consisted of a Waters ACQUITY UPLC® I-Class, coupled with a Waters XEVO TQ-XS triple quadrupole mass spectrometer. The method was developed and fully validated according to international guidelines. Limits of detection were set as the minimum criterion to identify positive samples. Overall, 56 samples resulted positive for ketamine, 35 for norketamine, 6 for fentanyl, 3 for norfentanyl, 3 for 4-ANPP, 3 for MDMB-4en-PINACA, 2 for N,N-DMT, 2 for 5-chloro AB-PINACA, 1 for α-PHP and 1 for methcathinone. NPS were detected in a small part of samples (8.4%), which seems in contrast with their apparent wide diffusion in Italy, yet it is congruent with similar investigations based on hair analysis. Future studies will be performed to expand the investigated population, especially in terms of age and origin.

Possibility of drug-distribution measurement in the hair of drowned bodies: evaluation of drug stability in water-soaked hair using micro-segmental analysis

In postmortem examinations, the drug analysis of hair is effective for revealing drug-use history. Additionally, a method to estimate the day of death using hair was previously developed by analyzing a single hair strand segmented at 0.4-mm intervals (micro-segmental hair analysis). However, for drowned bodies, drugs in the hair may be washed out due to soaking in water for extended periods. To evaluate the possibility of measuring drug distribution in the hair of drowned bodies, drug stability in hair samples soaked in various aqueous solutions was examined. First, reference hair strands of drug users containing specific drugs consistently along the hair shaft were prepared. The participants ingested 4 hay-fever medicines (fexofenadine, epinastine, cetirizine, and loratadine) every day for approximately 4 months before hair collection. Each reference strand was divided into regions, and each region was soaked in different solutions containing various solutes for extended periods up to approximately 2 months. In solutions without divalent ions (Ca²⁺ and Mg²⁺), the drug content in the hair decreased up to approximately 5 % with increasing salt concentration and soaking time. However, the decreased drug content was negligible in solutions containing divalent ions, implying that the divalent ions prevented drugs contained in hair from washing out. As natural river and sea waters contain divalent ions, the drugs in hair were hardly washed out even when the hair was soaked for 2 months. Thus, it was concluded that drug-distribution measurements using micro-segmental analysis can also be applied to the hairs of drowned bodies.

Fast and Sensitive Method for the Determination of 17 Designer Benzodiazepines in Hair by Liquid Chromatography-Tandem Mass Spectrometry

In recent years, identification and analysis of designer benzodiazepines have become a challenge in forensic toxicology. These substances are analogues of the classic benzodiazepines, but their pharmacology is not well known, and many of them have been associated with overdoses and deaths. As a result, there has been a surge in efforts to develop analytical methods to determine these compounds in different biological samples. Our aim was to develop and validate a fast, sensitive, and specific method for determining 17 designer benzodiazepines (adinazolam, clobazam, clonazolam, delorazepam, deschloroetizolam, diclazepam, etizolam, flualprazolam, flubromazepam, flubromazolam, flunitrazolam, N-desmethylclobazam, nifoxipam, nitrazolam, meclonazepam, pyrazolam and zolazepam) in hair by liquid chromatography-tandem mass spectrometry (LC-MS-MS). Hair samples were decontaminated, pulverized, and a 20-mg aliquot was incubated in methanol in an ultrasound bath (1h, 25ºC). The supernatant was evaporated and reconstituted in 200 µL of mobile phase, and the extracts were filtered (nano-filter vials) before injection into LC-MS-MS. All analytes eluted from the chromatographic column in 8 min, and two multiple-reaction monitoring (MRM) transitions were used to identify each compound. The limits of quantification were 5 or 25 pg/mg, depending on the analyte, and calibration functions were linear to 200 pg/mg. Imprecision was <19.2% (n = 15) and bias was from -13.7 up to 18.3% (n = 15). All the analytes yielded high extraction efficiencies >70%, and displayed ion suppression between -62.8% and -23.9% (n = 10). The method was applied to 19 authentic cases. Five samples were positive for flualprazolam (<LOQ - >200 pg/mg) and/or etizolam (47.4-88.5 pg/mg). In conclusion, the present validated method has proven to be fast, sensitive, specific, and capable of determining 17 designer benzodiazepines in hair using LC-MS-MS.