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Δ 9 -Tetrahydrocannabinol (Δ 9 -THC) is usually the primary psychoactive agent in cannabis preparations. Recently, products containing another isomer, Δ 8 -tetrahydrocannabinol (Δ 8 -THC), have become available for sale. Δ 8 -THC exists naturally in the cannabis plant at very low concentrations; hence, the Δ 8 -THC present in most of the above-mentioned products is likely to be manufactured synthetically. A surge in popularity of these products, coupled with little oversight to ensure purity and potency, has led to reports of adverse events. Workplace drug testing programs as well as many sporting organizations prohibit the use of cannabinoids. Carboxy-Δ 9 -THC (Δ 9 -THC-COOH) is the targeted urinary metabolite for detection of cannabis use. The proliferation of products containing Δ 8 -THC, which metabolizes to Δ 8 -THC-COOH, presents analytical complexity with respect to separation and quantification of the individual isomers as well as legal complexity with respect to lack of clarity around the legal status of Δ 8 -THC. This study aims to estimate the prevalence of Δ 8 -THC use in the athlete community by monitoring for Δ 8 -THC-COOH in samples collected for antidoping. A high-performance liquid chromatography tandem mass spectrometry (LC-MS/MS) method was utilized to resolve Δ 8 and Δ 9 -THC-COOH. One thousand samples with a presumptive Δ 9 -THC-COOH finding in routine screening were analyzed by the above LC-MS/MS method. Approximately 12% of samples contained Δ 8 -THC-COOH at relative abundances between 5% and 100% of total carboxy-THC content., (© 2024 John Wiley & Sons Ltd.)

The applicability of urinary minimum reporting limits (MRLs) to determine in-competition use of prohibited substances is an evolving topic. Most stimulants are subject to a universal MRL, despite the wide range of commercially available dosages for commonly used stimulants. Further, it is unknown whether the urinary MRL is reflective of a pharmacological dose ingested after the start of the in-competition period. To evaluate whether urinary MRLs can distinguish between in-competition and out-of-competition use, a controlled administration study was performed with three commonly used stimulants-amphetamine, methylphenidate, and modafinil at relatively low but therapeutically relevant dosages. Four to six volunteers were administered a particular drug once per day for five consecutive days. Urine, serum, dried blood spots (DBS), and oral fluid (OF) were collected during the active administration period and for 48 h after cessation of use. For all participants, urinary concentrations for all target analytes exceeded the MRL even 48 h after cessation of use. In serum and DBS, most volunteers showed detectable amounts at 48 h post use. Peak concentrations were variable between target compounds even with similar administered dosages. Further, there was a reproducible difference between serum and DBS concentrations. Interpretation of results from OF measurements was challenging due to the inability to normalize for hydration status and OF viscosity. Analyte concentrations decreased steadily over the washout period but did not correlate across matrices for all target analytes. The study reiterates the challenges associated with determining in-competition use by relying on urinary concentrations., (© 2024 John Wiley & Sons Ltd.)

19-Norandrosterone (19NA) is the preferred urinary target compound to identify doping with nandrolone or related 19-norsteroids. At concentrations between 2.5 and 15 ng/mL, isotope ratio mass spectrometry (IRMS) is required to establish exogenous origin of urinary 19NA. An absolute difference of 3‰ between urinary 19NA and an endogenous reference compound (ERC) constitutes a finding for exogenous origin of 19NA. Over the last 3 years, 77 samples containing urinary 19NA between 2.5 and 15 ng/mL were analyzed at our laboratory. The measured δ 13 C values for 19NA ranged from -29.5‰ to -16.8‰. In comparison, the δ 13 C values for the corresponding urinary ERCs ranged from -22.4‰ to -16.2‰. Due to the considerable overlap in values between the target compound and the natural range of urinary ERCs, it can be challenging to distinguish between endogenous and exogenous origins of urinary 19NA. In addition, it is well known that consumption of offal from non-castrated pigs can produce 19NA in urine. To determine whether this could cause a positive IRMS finding under the current IRMS positivity criteria, meat from non-castrated boars fed a mixture of corn and soy was consumed by 13 volunteers. Two volunteers produced 19NA findings above 2.5 ng/mL, and the measured isotope values, while inconsistent with documented 19-norsteroid preparations, did meet IRMS positivity criteria. However, these increases in 19NA urinary concentrations were short-lived due to rapid elimination. Timely follow-up collections may help support a claim for dietary exposure when low urinary concentrations of 19NA with pseudo-endogenous isotope values are observed., (© 2023 John Wiley & Sons Ltd.)