Synthesis and characterization of barbarin, a possible source of unexplained aminorex identifications in forensic science.

Aminorex is a US DEA Schedule 1 controlled substance occasionally detected in racing horses. A number of aminorex identifications in sport horses were thought to have been caused by exposure to plant sources of aminorex. Glucobarbarin, found in plants of the Brassicaceae family, has been suggested as a potential proximate chemical source by being metabolized in the plant or the horse to aminorex. In Brassicaceae, glucobarbarin is hydrolyzed by myrosinase to yield barbarin, which serves as an insect repellant and/or attractant and is structurally related to aminorex. The synthesis, purification, and characterization of barbarin is now reported for use as a reference standard in aminorex related research concerning equine urinary identifications of aminorex and also for possible use in equine administration experiments. Synthesis of barbarin was performed via ring closure between phenylethanolamine and carbon disulfide in tetrahydrofuran with the catalyst pyridine under reflux. The reaction yielded a white crystalline substance that was purified and chemically characterized as barbarin for use as a Certified Reference Standard or for studies related to equine aminorex identification.

A cluster of trace-concentration methamphetamine identifications in racehorses associated with a methamphetamine-contaminated horse trailer: A report and analysis.

Three low concentration methamphetamine "positive" tests were linked to use of a methamphetamine-contaminated trailer to transport the affected horses. This incident establishes methamphetamine as a human-use substance that can inadvertently enter the environment of racing horses, resulting in urinary methamphetamine "positives;" an interim regulatory cut-off of 15 ng/mL for methamphetamine in post-race urine is proposed.

Identifications de concentrations de méthamphétamine à l'état de traces chez des chevaux de course associées à une remorque contaminée : rapport et analyse. Trois tests «positifs¼ de faibles concentrations de méthamphétamine ont été associés à l'utilisation d'une remorque contaminée par les méthamphétamines qui était utilisée pour transporter les chevaux affectés. Cet incident établit la méthamphétamine comme une substance à utilisation humaine qui peut pénétrer par inadvertance dans le milieu des chevaux de course, entainant ainsi des tests d'urine «positifs¼; un niveau intérimaire réglementaire de 15 ng/mL pour les méthamphétamines est proposé pour les tests d'urine après la course.(Traduit par Isabelle Vallières).

A protocol to evaluate drug-related workplace impairment.

The dramatic increase in the use and abuse of prescription controlled substances, cannabis, and a rapidly evolving array of legal and illegal psychotropic drugs has led to a growing concern by employers about workplace impairment, incidents, and accidents. The Federal Workplace Drug Testing Programs, which serve as a template for most private sector programs, focus on a small group of illicit drugs, but disregard the wider spectrum of legal and illegal psychotropic drugs and prescription controlled substances. We propose a protocol for the evaluation of workplace impairment, based on comprehensive drug and alcohol testing at the time of suspected impairment, followed expeditiously by a comprehensive physician evaluation, including a focused medical history with an emphasis on controlled substance use, physical and mental status examinations, evaluation of employee adherence to prescription medication instructions, additional drug testing if indicated, use of collateral sources of information, and querying of state prescription monitoring databases. Finally, we propose suggestions for optimizing the evaluation of drug-related workplace impairment.