Toxicology

Investigate opioid concentrations in individuals (e.g., cancer patients) experiencing severe chronic pain within a clinical or outpatient system. Particularly interested in the pediatric population (i.e., 18 years of age or less) and patients receiving hydromorphone.

Individuals who experience severe chronic pain are often prescribed opioid medications (e.g., morphine, oxycodone, methadone, hydromorphone, etc.) on a long-term basis in order to achieve pain control for better quality of life. However, the repeated use of opioids typically results in the development of tolerance whereby the individual requires increasingly larger doses to maintain an effective analgesic outcome. Studies of opioid concentrations in patients who chronically receive high doses are very limited. Opioid-tolerant individuals will exhibit serum opioid concentrations which could be toxic or lethal in naive users. The limited published literature on serum/blood opioid levels in living chronic opioid patients may lead to the forensic misinterpretation of post-mortem blood opioid concentrations.

To document opioid concentrations in highly tolerant patients and thereby more accurately interpret post-mortem opioid blood concentrations in death investigations.

To contribute to the medico-legal literature related to the opioid tolerance seen in patients receiving high doses of opioids while being treated for severe chronic pain.

• Access to individuals receiving high-dose opioids within a clinical or outpatient system and ability to collect whole blood samples using sterile technique.
• Ability to collect limited, but relevant patient information (e.g. age, sex, opioids used, dosing, length of opioid therapy, etc.).
• Review current literature and draft study design.
• Prior publication experience is valuable but not required.

The CFS will conduct all extractions & analyses using current standard operating procedures (i.e. LC-MS/MS).

Drug use among Automobile drivers in Ontario Background: Impaired driving is the leading criminal cause of death and injury in Canada, and drug-impaired driving is increasing

To retrospectively examine Toxicology section case results to test the hypothesized that the number of drug-involved driver fatalities now rivals, and possibly exceeds, the number involving alcohol.

Examine drug use among two populations of Ontario drivers – those fatally injured in motor vehicle collisions and those arrested and evaluated by a Drug Recognition Evaluator. Data from case files compiled by the Toxicology section of the Centre of Forensic Sciences from 2018 to 2020 will be analyzed to gain a better understanding of the types of drugs used by drivers, the demographic characteristics of those involved (e.g., age group, sex), and the circumstances of the event (e.g., month of occurrence, day of week, time of day). Comparisons of drug-involved driver fatalities with drug-driving arrests will outline similarities and differences in these two populations and provide insights into how enforcement activities might better target those drug drivers most likely to crash.

Expertise evaluating and analysing data.

Data is available from case records. Data will be anonymised prior to sharing with partner.

The Cannabis Act came into effect on October 17 2018, which outlines a strict framework for controlling the sale, possession, production and distribution of cannabis in Canada. There remain concerns that recreational cannabis legalization may affect the perceived harmfulness of cannabis use.

Current evidence concerning the impact of recreational cannabis legalization on traffic injuries from jurisdictions in the United States is mixed (1-4). Importantly, the generalizability of this evidence to the context in Canada is limited, given the differences between the two countries in socio-legal environments.

Our research aim is to examine the impact of cannabis legalization on traffic injury deaths based on toxicological analyses of blood samples from 2015 to 2020. We anticipate using time series analysis methods with monthly or quarterly data.

Potential research questions include:

1. Does recreational cannabis legalization result in increases in rates of traffic injury deaths with detection of cannabis?

2. Does recreational cannabis legalization result in decreases in rates of traffic injury deaths with detection of alcohol?

3. Does recreational cannabis legalization result in decreases in rates of traffic injury deaths with detection of other drugs?

4. How have the rates of traffic injury deaths with detection of cannabis, alcohol and other drugs changed from the pre-recreational cannabis legalization period to the post-recreational cannabis legalization period for non-highway vehicles (e.g. ATVs, boats, bicycles?

5. Have demographic characteristics and collision characteristics of traffic injury deaths with detection of cannabis, alcohol and other drugs changed from the pre-recreational cannabis legalization period to the post-recreational cannabis legalization period?

Systematic review of literature to develop tables of published data related to alcohols effect on psychomotor and driving performance and compare these effects to published data of other drugs.

Interpretation in forensic toxicology relies on the objective evaluation of literature related to a given question. For drug effects related to impairing an individual’s ability to operate a motor vehicle, this can typically be achieved by a review of the literature as it relates to clinical/laboratory effects of drugs, simulator or on-road driving studies and when available, epidemiological studies of prevalence and crash risk for drug classes. Meta-analysis of data allows for the compilation of multiple studies to increase the strength of an interpretive opinion. Further, collecting data from multiple studies and presenting it to answer a forensically relevant question may allow for the development of models that asses the relative strength of an opinion/conclusion in a given report (towards evaluative reporting).

Evaluation of toxicological effects of the combination of opioids and benzodiazepines detected in forensic casework

In toxicology, international classification systems focus on single intoxicants as the cause of death. It is, however, well known that very few drug related deaths are caused by a single substance and that information concerning the drug concentrations as well as the combinations of drugs are essential in order to ascertain the cause of death.

This research would investigate cases where opioids, benzodiazepines and naloxone have been detected over the last 5 years to provide valuable information about the potential toxicity of concurrent use of opioids and benzodiazepines. Although the toxicity of opioids in combination with benzodiazepines is the primary focus of the study inclusion of naloxone in this project reflects recent capabilities for its detection implemented in the toxicology section. It is relevant to the combination of opioids and benzodiazepines because as an opioid antagonist, it is ineffective against benzodiazepine overdose. The expected outcome is to enhance the ability of Toxicology scientists to interpret poly-drug findings involving the above stated drugs.

Contribute to literature reporting on the combined effects of benzodiazepines, opioids and opioid antagonists

Researcher is required to have obtain access to case files stored at the Toxicology section of the CFS and have a police background check to show no criminal record and be able to complete a confidentiality agreement.

CFS case files and expertise