Adult notification rate was the lowest since 2014, while the rate for children has halved since 2018
There were a total of 44 hazardous substance notifications in 2020, 32 of which were adults (15 years and over), and 12 were children (0 to 14 years).
The hazardous substances notification rate for adults in 2020 (0.8 per 100,000) was the lowest since 2014. The rate for children remained fairly stable between 2014 and 2017, but increased in 2018. Since then, the rate has halved, dropping from 3.0 per 100,000 in 2018 to 1.2 per 100,000 in 2020 (Figure 1).
Lower notification rates in 2020 for both adults and children may have been impacted by the COVID-19 nationwide lockdown.
Figure 1: Hazardous substances notification rate, by age group, 2014–20 (crude rate per 100,000)
Males and females aged under 25 years have similar rates of hazardous substances notifications in 2014–20
From 2014–20, males and females aged under 25 years have similar rates of hazardous substances notifications (Figure 2). However, for people aged 25 years and over, the notification rates were statistically significantly higher for males than females.
Figure 2: Hazardous substances notification rate, by sex and age group, 2014–20 (Age-specific rate per 100,000)
A significant drop in the hazardous substances notification rate for children under five years in 2020
In 2020, the hazardous substances notification rate in the 0–4 year age group has dropped significantly, from 6.6 per 100,000 (20 notifications) in 2019 to 2.9 per 100,000 (9 notifications) in 2020 (Figure 3).
Figure 3: Hazardous substances notification rate, by age group, 2014–20 (Age-specific rate per 100,000)
Pacific peoples had a slightly higher hazardous substances notification rate than other ethnic groups
In 2014–20, Pacific peoples had a slightly higher hazardous substances notification rate than other ethnic groups, with the rate of 2.0 per 100,000 (44 notifications) (Figure 4).
Figure 4: Hazardous substances notifications rate, by ethnicity (prioritised), 2014–20 (crude rate per 100,000)
Higher hazardous substances notifications rates in Hutt Valley, Wairarapa and Capital & Coast DHBs
In 2014–20, people living in the Hutt Valley, Wairarapa and Capital & Coast DHBs had higher rates of hazardous substances notifications compared to other DHBs (Figure 5). This was the same in 2014–19. These are most likely due to increased use of the HSDIRT in these areas rather than an increased exposure to hazardous substances. Rates in Lakes, West Coast, South Canterbury and Southern DHBs were suppressed due to low numbers of notifications (<5) reported.
Figure 5:Hazardous substances notification rate, by District Health Board, 2014–20 (crude rate per 100,000)
Ammonia and carbon monoxide were the most commonly notified substances in 2020
In 2020, the most commonly identified substances were carbon monoxide (5 notifications) and ammonia (4 notifications) (Figure 6).
In 2020, 40.9% (18) of the substances were household chemicals, 36.4% (6) were industrial chemicals, 15.9% (7) were other chemicals and 6.8% (3) were agrichemicals.
In 2020, there were four incidents where accidental ingestion occurred due to inappropriate storage of chemicals in bottles other than their original containers. Three of these were children under the age of ten years old.
Figure 6: Number of hazardous substances notifications, 2020
The majority of hazardous substances injuries notified were unintentional across all age groups in 2014–20
When investigating hazardous substances injuries, intent is categorised as either intentional, unintentional or unknown by the public health unit.
In 2014–20, the majority of the hazardous substances injuries notified were unintentional across all age groups (Figure 7).
Figure 7:Hazardous substances notifications, by intent and age group, 2014–20 (% of total notifications)
The most common route of exposure for children under five was ingestion
In 2014–20, the most common route of exposure for children under five years was ingestion (60 out of 84 notifications) (Figure 8). Children, especially under the age of five, commonly spend time exploring their surroundings at home, with regular hand-mouth contact with items they encounter there. If they gain access to hazardous substances, especially if stored incorrectly or unsafely, this can lead to unintentional exposures (Safekids Aotearoa, 2015). Whereas for other age groups, their most common route of exposure was inhalation.
Figure 8: Number of notifications, by exposure route and age group, 2014–20
Information about the data
This indicator reports HSDIRT hazardous substances notifications from 2014 to 2020. The data was extracted from the HSDIRT system on 5 March 2021. Updates or additions made to HSDIRT after this date are not reflected in this factsheet.
Data have sometimes been pooled to give sufficient numbers for analysis.
Crude rates presented in this factsheet do not take into account varying age distributions when comparing between populations.
For additional information, see the metadata.
1. BPAC. 2014. Hazardous Substance poisoning in children:poisons in and around the house. URL: https://bpac.org.nz/BPJ/2014/March/hazardous.aspx (Accessed 7 October 2021)
2.Ministry Of Health. 2019. The Investigation and Surveillance of Poisoning and Hazardous-substance Injuries: Guidelines for public health units (4th edn). Wellington: Ministry of Health.
3. Safekids Aotearoa. 2015. Position Paper: Child Poisoning Prevention. Auckland, Safekids Aotearoa, 2015.
4. Worksafe – Mahi Humaru Aotearoa. 2017. Information on Hazardous Substances. URL: https://worksafe.govt.nz/topicand-industry/hazardous-substances/about-hazardous-substances/ (Accessed 21 September 2021)