The coroner is a public officer (doctor, lawyer, or notary) appointed by the provincial government who reports to the Chief Coroner. The coroner systematically intervenes to determine the cause of death in a number of situations, including when a death occurs under violent (e.g., accident, suicide) or mysterious circumstances, when the death is the result of negligence, when the cause of death is unknown, or when the death occurs in a rehabilitation centre, penitentiary, detention centre, intensive supervision unit as defined in the Youth Protection Act, police station, daycare centre, or foster family, or in custody in a health facility, etc. In Québec, nearly 10% of deaths are reported to Bureau du coroner du Québec (BCQ). Following the investigation, the coroner publishes his or her findings in a public report.
Although a coroner’s report can take an average of 10 to 12 months to produce, information on the presumed causes and circumstances of the death are generally recorded in a database within 48 hours after the death is reported. Together with the results of the toxicological analyses that are frequently requested by coroners and are generally available within a few weeks, this information is a useful data source for quickly identifying threats to the public’s health or emerging phenomena involving exposure to or consumption of chemicals.
Definitions of health vigilance and toxicovigilance
Health vigilance is defined by Ministère de la Santé et des Services sociaux (MSSS) as a continuous process of identifying and characterizing threats to population health through the collection, analysis, and interpretation of data on health determinants and effects. It enables MSSS to detect real or perceived health threats as early as possible and to alert public health authorities so they can respond appropriately (MSSS, 2014). Health vigilance differs from surveillance in that it involves an active process of identifying health threats.
The term toxicovigilance is used when health vigilance focuses on toxicants. Although MSSS does not have a definition of toxicovigilance, the World Health Organization (WHO) has defined it as an active process of identifying and evaluating toxic risks with the aim of reducing the incidence of poisonings by identifying new toxicological risks (WHO, n.d.).
For more information on the definitions of toxicovigilance and the differences between surveillance, toxicovigilance, and pharmacovigilance, the reader is encouraged to consult the publication by Vermette, Dubé, and Gosselin (2014).
Objectives of the literature review
The first objective of this literature review was to guide the development of appropriate toxicovigilance indicators for Québec by surveying toxicovigilance activities that use toxicological analysis data compiled by coroners and medical examiners on deceased persons. Given the absence of scientific literature on such toxicovigilance activities, the objective was revised in order to collect information on substances and populations targeted by similar surveillance activities, namely activities using toxicological analysis data compiled by coroners and medical examiners on deceased persons in Canada and around the world. This review also describes the main advantages and disadvantages of using data from ongoing coroners’ and medical examiners’ investigations for toxicovigilance purposes.
It was possible to determine that the vast majority of substances investigated or detected through surveillance activities or population surveys (related to deaths by poisoning) are drugs or medications. However, this observation must be qualified by the fact that most toxicological analyses carried out on deceased persons prioritize some of these substances at the expense of others, such as pesticides or industrial products. Nevertheless, in Québec, drugs and medications alone are responsible for a very high proportion of deaths due to poisoning. It is important to keep in mind, however, that health surveillance initiatives must also address rare or unusual phenomena that are not necessarily detected using existing surveillance activities.