Indicators at a glance - hazardous substances

This section summarises the latest Environmental Health Indicators about hazardous substances in New Zealand.

A hazardous substance is anything that can explode, catch fire, oxidise, corrode or be toxic to humans, as defined in the Hazardous Substances and New Organisms Act (HSNO) 1996. Substances that are covered by the HSNO Act, and the Health Act’s “poisoning arising from chemical contamination of the environment”, in particular carbon monoxide, are included.

Medicines in finished dose form, alcohol when classified as a food item, chemical toxins associated with food (food poisoning), and radioactive materials are excluded.

Health effects of hazardous substances Key findings

Hazardous substances-related deaths reported to the coroner in New Zealand

  • There were 10 hazardous substance-related deaths reported to the coroner in 2019, and eight in 2018. The rate continues to decrease over time, although the number of deaths fluctuated year-to-year, since 2008. 
  • Since 2008–12, the number of deaths for males have been consistently higher than for females 
  • Approximately 40% of the deaths occurred in the 15–34 year age group, while there were no deaths for children under five years old. 
  • Butane and other hydrocarbons were the most common cause of death for ages 15–24 and carbon monoxide poisoning for ages 25–74 in 2008–19. 
  • The percentage of butane and other hydrocarbons deaths in ages 15–24 has decreased by 73% from 2008–13 to 2014–19. 
  • The hazardous substances mortality rate for Māori has decreased from 2008 onwards, while the rate for non-Māori has remained unchanged. 
Unintentional hazardous substances-related hospitalisations                                                              
  • In 2020, there were 419 unintentional hazardous substances-related hospitalisations. The rate has fallen since 2001, and this was driven primarily by decreasing rates among males. 
  • Children under five years have had the highest hospitalisation rate every year since 2001. 
  • Children under five years have the highest hospitalisation rates for ‘Other and unspecified chemicals and noxious substances’, ‘Organic solvents and halogenated hydrocarbons and their vapours’ and ‘Pesticides’.
  • The hospitalisation rates for ‘Exposure to ignition of highly flammable material’ in the 15–24 year age group has dropped by 72.5% between 2001–05 and 2016–20.
  • The top three substances/substance categories resulting in hospitalisation in 2020 were chemical and noxious substances, petrol, corrosive substances and other gases. 
  • Māori had a higher hospitalisation rate than non-Māori in 2020.
  • People living in the most deprived areas (NZDep 2018 quintile 5) have a higher hospitalisation rate than those in the least deprived areas in 2020. 
  • The West Coast District Health Board had the highest hazardous substances-related hospitalisation rate in the last ten years. 

Occupational lead absorption notifications

  • The occupational lead absorption notification rate has decreased from 3.0 per 100,000 (122 notifications) in 2019 to 1.4 per 100,000 (59 notifications) in 2020. The lower rate in 2020 may have been impacted by COVID-19 nationwide lockdown.
  • Over 90% of the occupational lead notifications were males in 2014–20
  • There were no significant differences in blood lead levels from occupational exposures between age groups in 2014–20
  • Pacific workers had the highest occupational lead absorption notification rate in 2014–20
  • Painters have remained the most notified group with lead absorption since 2014. 
  • Workers living in the most deprived areas (NZDep2018 quintile 5) were nearly 2.5 times as likely to have occupational lead absorption as those in the least deprived areas in 2014–20.
  • The Wairarapa District Health Board (DHB) had the highest reported occupational lead absorption rate. The Public Health Unit (PHU) with the highest reported rate was Regional Public Health.
Non-occupational/unknown source of lead absorption notifications           
  • The non-occupational/unknown source of lead absorption notification rate has decreased from 2.1 per 100,000 (94 notifications) in 2014 to 1.2 per 100,000 (62 notifications) in 2020. 
  • Over 80% of the non-occupational/unknown source of lead absorption cases were males. Only boys in the 0–4 year age group had higher blood lead levels than girls of the same age group. 
  • Non-occupational/unknown source of lead absorption notification rate among European/Other ethnicity is over three times the rate among Māori. 
  • People living in the most deprived areas (NZDep2018 quintile 5) have a higher lead absorption rate than those in less deprived (NZDep2018 quintile 2) areas in 2014–20.
  • Lead-based paint has remained the most common source of non-occupational lead absorption since 2014.
  • People exposed to lead-containing cosmetics or traditional medicines have relatively higher blood lead levels.
  • The Wairarapa District Health Board (DHB) had the highest reported non-occupational/unknown source of lead absorption rate. The Public Health Unit (PHU) with the highest reported rate was Taranaki DHB Public Health Unit.

Hazardous substances notifications

  • In 2020, there were 44 (32 adults and 12 children) hazardous substances notifications. The rate for adults in 2020 was the lowest since 2014, while the rate for children has halved since 2018. 
  • Males and females aged under 25 years have similar rates of hazardous substances notifications in 2014–20. 
  • There was a statistically significant drop in the hazardous substances notification rate for children under five years only in 2020. 
  • Pacific peoples had a slightly higher hazardous substances notification rate than other ethnic groups in 2014–20. 
  • The hazardous substances notification rate was higher in the most deprived areas (NZDep 2018 quintile 5) than the least deprived areas (NZDep 2018 quintile 1) in 2014–20. 
  • Carbon monoxide and ammonia were the most commonly notified substances in 2020. [
  • Four of the incidents involved storage of chemicals in an inappropriate container in 2020. Three of these were children under ten years old. 
  • The majority of the hazardous substances injuries notified were unintentional across all age groups in 2014–20. 

Unintentional hazardous substances exposures in children (0–14 years); calls to the National Poisons Centre in 2017–2019

  • On average, there were more than 1,000 exposure calls per quarter between 2017 to 2019 relating to unintentional hazardous substance exposures involving children aged 0–14. 
  • Children aged one had the highest rates of exposures. 
  • Although boys were exposed to hazardous substances more often than girls, boys were only 1.1 times as likely as girls to be exposed to substances. 
  • Children of European/Other ethnicity had the highest rates of exposures when compared to other ethnic groups. 
  • Most exposures involved the ‘household anti-infective/cleaners’ category of substances, which was the most common cause of concern in children aged one. 
  • Approximately 93% of the exposures occurred in the home environment. The top three hazardous substances reported were: dishwashing liquid (645 exposures), toilet bowl discs (637) and essential oils (570). 
  • While 87% of the exposures were safe to manage without further medical assessment, every situation should be checked with the NPC to determine the safest course of action.
  • Two-thirds of the exposures contacted the NPC within an hour. Therefore, contacting NPC as early as possible is critical to provide appropriate advice to the patient for any exposure or suspected exposures.
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