Matthew DiRago

Bio: Matthew DiRago is an academic researcher from Monash University. The author has contributed to research in topics: Occupational safety and health & Injury prevention. The author has an hindex of 1, co-authored 1 publications receiving 7 citations.

Prevalence of drugs in injured drivers in Victoria, Australia

Abstract: This study documents the prevalence of positive tests for alcohol and a large number of drugs in drivers taken to Victorian hospitals for injuries over a five-year period. Blood specimens w...

Trace residue identification, characterization, and longitudinal monitoring of the novel synthetic opioid β‐U10, from discarded drug paraphernalia

Abstract: Abstract Empirical data regarding dynamic alterations in illicit drug supply markets in response to the COVID‐19 pandemic, including the potential for introduction of novel drug substances and/or increased poly‐drug combination use at the “street” level, that is, directly proximal to the point of consumption, are currently lacking. Here, a high‐throughput strategy employing ambient ionization‐mass spectrometry is described for the trace residue identification, characterization, and longitudinal monitoring of illicit drug substances found within >6,600 discarded drug paraphernalia (DDP) samples collected during a pilot study of an early warning system for illicit drug use in Melbourne, Australia from August 2020 to February 2021, while significant COVID‐19 lockdown conditions were imposed. The utility of this approach is demonstrated for the de novo identification and structural characterization of β‐U10, a previously unreported naphthamide analog within the “U‐series” of synthetic opioid drugs, including differentiation from its α‐U10 isomer without need for sample preparation or chromatographic separation prior to analysis. Notably, β‐U10 was observed with 23 other drug substances, most commonly in temporally distinct clusters with heroin, etizolam, and diphenhydramine, and in a total of 182 different poly‐drug combinations. Longitudinal monitoring of the number and weekly “average signal intensity” (ASI) values of identified substances, developed here as a semi‐quantitative proxy indicator of changes in availability, relative purity and compositions of street level drug samples, revealed that increases in the number of identifications and ASI for β‐U10 and etizolam coincided with a 50% decrease in the number of positive detections and an order of magnitude decrease in the ASI for heroin.

Epidemiology of drug driving: protocol from a national Canadian study measuring levels of cannabis, alcohol and other substances in injured drivers.

Abstract: Drug driving is an emerging global road safety problem. As the prevalence of alcohol-impaired driving decreases, and as more jurisdictions decriminalize or legalize cannabis, it is increasingly important for policy makers to have accurate information on the prevalence and pattern of drug driving. Unfortunately, this data is not widely available and the World Health Organization identifies lack of accurate data on the prevalence of drug driving as an important knowledge gap. In this paper, we discuss the limitations of current methods of monitoring drug use in drivers. We then present a novel methodology from a multi-centre study that monitors the prevalence and pattern of drug use in injured drivers across Canada. This study uses “left-over” blood taken as part of routine medical care to quantify cannabis and other drugs in non-fatally injured drivers who present to participating emergency departments after a collision. Toxicology testing is done with waiver of consent as we have procedures that prevent results from being linked to any individual. These methods minimize non-response bias and have the advantages of measuring drug concentrations in blood obtained shortly after a collision. Our methods can be applied in other jurisdictions and provide a consistent approach to collect data on drug driving. Consistent methods allow comparison of drug driving prevalence from different regions. Data from this research can be used to inform policies designed to prevent driving under the influence of cannabis and other impairing drugs.

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Abstract: Positive oral fluid test results may indicate recent cannabis use because test sensitivity is usually limited to a few hours after smoking (the time depending upon the detection threshold of the device). 9 THC in oral fluid primarily represents coating of the mouth after inhalation of drug-laden smoke or vapour. It is not associated with THC concentrations in blood or driver performance. 2 Two to four hours after cannabis intake, coating of the oral fluid dissipates and oral fluid THC concentrations approximately parallel blood THC concentrations, but not at the same levels. 10 We cannot accurately predict blood concentrations of THC from oral fluid concentrations because of high intra-subject and inter-subject variability. 11