SOFT 2004 Meeting Abstracts - Society of Forensic Toxicologists

P26
A RETROSPECTIVE STUDY OFOXYCODONE DEATHS IN ONTARIO 1999-2003
lCentre of Forensic Sciences, 25 Grosvenor St, Toronto, Ontario, M7A 208. 2Northem Regional Forensic
Laboratory, Centre of Forensic Sciences, 70 Foster Dr, Sault Ste. Marie, Ontario, P6A 6V3. 30ffice of the
Chief Coroner, 26 Grenville St, Toronto, Ontario, M7A 2G9.
This report presents the results of a retrospective study aimed at determining the role of oxycodone in
deaths investigated by the Office of the Chief Coroner in Ontario, Canada, between 1999 and 2003. The
objectives of the study were 1) to assess changes over this period in the prevalence of oxycodone in deaths
investigated by the coroners, and 2) to assess the extent to which these deaths were oxycodone-induced or
oxycodone-related. The cases included in this study were death investigations in which specimens obtained
from a medico-legal autopsy, were submitted to the Centre of Forensic Sciences for a toxicological
examination. In all but three cases, examinations consisted of analysis for alcohols, a general drug
screening procedure that detects a range of therapeutic agents and illicit substances that exhibit central
nervous system toxicity and are encountered in postmortem toxicology, and targeted analyses for the
quantitation and confirmation of screen findings. Cases were included in this study only when a blood
oxycodone finding was available. In the majority of cases, analysis was performed on heart blood, and in
others, on samples identified as femoral or peripheral venous, or from an unspecified source. Quantitation
of total oxycodone in whole blood was carried out using a liquidlliquid basic extraction, followed by a gas
chromatographic analysis using a nitrogen/phosphorous detector and capillary fused silica columns.
A total of 291 cases met the inclusion criteria for this study, representing 194 males and 97 females.
Oxycodone-positive cases submitted to this laboratory in 1999 numbered 22 and increased steadily each
year to reach 101 in 2003. The increase in annual submissions was markedly disproportionate to the
overall increase in submissions. Although no attempt was made in this phase of the study to determine
whether the detected oxycodone was due to the ingestion of Oxycontin® or any other oxycodonecontaining
formulation, it is noteworthy that the increase in the prevalence of oxycodone findings in death
investigations coincides with the introduction of Oxycontin® to the Canadian market in about 1996. In
order to assess the involvement of oxycodone in these deaths, the coroner's conclusion regarding the cause
of death was recorded. In 39 cases over this five-year period, death was attributed to natural causes or
trauma, but not related to the presence of oxycodone. Blood oxycodone concentrations ranged from less
than 0.01 to 0.9 mg/L.
In the remaining cases (n == 252), death was determined by the coroner to be drug-induced or drug-related.
Based on the reported postmortem blood toxicology findings, cases were divided into four categories: 1)
oxycodone alone (2%); 2) oxycodone and other drugs in therapeutic concentrations, with ethanol present at
or below 50 mg/IOO mL (20%); 3) oxycodone and other drugs in potentially toxic concentrations, with
ethanol in excess of 50 mg/l00 mL (59%); and 4) oxycodone and other drugs in potentially fatal
concentrations (19%). The blood oxycodone concentration ranges for each group were 0.1 to 0.92 mg/L,
0.1 to 5.5 mg/L, less than 0.01 to 9.8 mglL, and 0.03 to 4.4 mg/L, respectively.
The observed overlap in blood oxycodone concentrations across these groups underscores the importance
of other factors such as polydrug use, drug formulation, and the experience of the user in assessing the
contribution ofoxycodone to the death.
Keywords: oxycodone, postmortem, toxicology
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