Poisoning has been defined as injury to, and destruction of, bodily cells through the ingestion, inhalation, injection or absorption of toxic substances (World Health Organization 2008). In Western countries there are two demographic peaks of poisoning activity and deaths. The first is unintentional exploratory poisonings, where children younger than six years of age (but typically between two and three years of age) ingest toxic substances. In these unintentional exploratory poisonings, there is no intent to self-harm, and substances ingested typically include household items such as cleaning agents, toiletries, medicines and plant materials. These poisonings account for a large number of health advice calls and medical consultations with significant numbers of hospital admissions, but very few deaths. As a result of education, identification of hazards and strategic interventions, the trend across developed countries has been a gradual decline in these poisoning deaths.
The second demographic peak increases from adolescence onwards to young adulthood and is related to risk-taking behaviour, recreational drug use and suicidal intent. Opioid drug use and alcohol account for significant numbers of deaths among New Zealand youth, while volatile substance abuse (VSA) has been the cause of most unintentional deaths. This issue was highlighted in the recent report from the Office of the Chief Coroner, in which 55 of the 63 deaths from recreational inhalation of volatile substances between 2000 and 2012 were young people under 24 years (Office of the Chief Coroner 2012).
New Zealand’s overall poisoning mortality statistics are in line with international findings (Belanger et al 2008; Beasley and Reith 2005; Hoppe-Roberts et al 2000), except that New Zealand has fewer cases of death under age five, with no unintentional poisoning deaths in New Zealand between 2002 and 2008 in this age group. This suggests that countrywide initiatives to decrease infant deaths by unintentional poisoning over the last 20 years have had a positive impact. Internationally, the highest fatality rate from unintentional poisonings is found in infants and preschool children, with a further peak around 15 years of age (World Health Organization 2008).
Over the last two decades, campaigns to increase parental awareness of storing household hazardous substances have had a positive impact. An increased responsiveness from the National Poisons Centre to emergency medical care, together with improved industry standards for packaging and sealing hazardous substances (eg, child-resistant lids and blister packs), have likely helped to contribute to a decline in infant poisoning deaths. Despite this, infants and children up to three years of age still remain one of the greatest risk groups when it comes to unintentional poisoning. Figures released by the New Zealand Accident Compensation Corporation (ACC) show that 60 percent of all new poisoning claims lodged with ACC were for injuries to children three years of age and under, accounting for approximately 34 percent of total ACC poisoning-related costs between 2002 and 2009.
New Zealand, like many other comparable OECD countries, faces the problem of extreme risk-taking behaviours, including substance abuse, in children and young people. International trends suggest patterns of substance abuse differ by age. Solvent and hydrocarbon abuse (eg, glue sniffing and butane inhalation) are prevalent in young adolescents, whereas alcohol abuse and the use of controlled or regulated substances (eg, prescription medicines or Class A and Class B drugs, such as heroin, cannabis oil, psilocybin and MDMA14) are more common in older teenagers and young adults (Beasley and Reith 2005; Hoppe-Roberts et al 2000; Reith et al 2005; McDowell et al 2005; Doogue and Barclay 2005; Pan et al 2006). Issues related to risk-taking were reviewed in the CYMRC’s Fifth Report to the Minister of Health (CYMRC 2009).
Although the focus of this report is poisoning mortality in young people, it is important to remember that the numerical burden of poisoning morbidity and hospitalisation sits with children under the age of five. It is a remarkable success story that no children died in this age group over this time period, but the CYMRC is aware of some deaths outside this time period and a substantial number of hospitalised cases – 2041 children under the age of five were discharged from hospital over the same time period as the fatal cases of poisoning reported here. There must be continuing work to reduce the number of these cases, and there is no scope to let up on current initiatives.
The content of this report has been limited to unintentional poisoning deaths and those of undetermined intent. Information on intentional poisoning deaths in New Zealand is contained as part of an extensive review of youth suicide, including suicide by poisoning, in the CYMRC’s Fifth Report to the Minister of Health (CYMRC 2009) and in the 2012 analysis of all-ages suicide deaths by poisoning (Gallagher et al 2012). The methodology used in this report misses harm done to the developing foetus through alcohol, tobacco and other substances. The harm is significant, contributes to poisoning deaths later and supports a recurring cycle.
The analyses in this report identify patterns and trends in deaths due to unintentional poisoning and poisoning of undetermined intent in New Zealand during 2002–08, setting them in context and attempting to identify ways to reduce the toll. This report is focused on young people, with most of the analyses presented showing poisonings in young people aged 15–24 years.
Deaths due to poisoning were the second most common cause of unintentional deaths and deaths of undetermined intent in the period 2002–08 for young people between the ages of 14 and 25, accounting for 6.8 percent of total unintentional injury deaths in New Zealand16 (CYMRC 2009). A recent World Health Organization investigation reported poisoning as the fourth biggest unintentional injury killer worldwide – after road traffic injuries, fires and drowning. This study noted that 13 percent of all unintentional poisoning deaths occurred in those aged under 20 (World Health Organization 2008).