The non-occupational/unknown source of lead absorption rate has decreased since 2014
In 2020, there were 62 non-occupational/unknown source of lead absorption notifications out of 110 lead notifications from all exposure sources. The non-occupational/unknown source of lead absorption notification rate has decreased from 2.1 per 100,000 in 2014 to 1.2 per 100,000 in 2020. The nationwide lockdown from COVID-19 may have contributed to the low rate in 2020.
Figure 1: Non-occupational/unknown source of lead absorption notification rate, by year
 There were 11 cases reported in both occupational and non-occupational/unknown categories. Therefore, these cases can add to more than the total number of lead notifications.
Over 80% of the non-occupational/unknown source of lead absorption cases were males
In 2014–20, 81% of the non-occupational/unknown source of lead absorption notifications were males (474 out of 587 non-occupational lead notifications), while 18% (105 notifications) were females and for 1% (8 notifications) sex was unknown.
Boys in the 0–4 year age group had higher blood lead levels than girls of the same age group
In 2014–20, out of all the age groups, only boys in the 0–4 year age group had higher blood lead levels than girls of the same age group. Other than that, there were no significant differences in blood lead levels from non-occupational exposures between sexes (Table 1).
Table 1: Median blood lead level, interquartile range and number of non-occupational/unknown source of lead notifications by age group and sex, 2014–20
Non-occupational/unknown source of lead absorption notification rate among European/Other ethnicity is over three times the rate among Māori
In 2014–20, people of European/Other ethnicity were 3.3 times as likely to have non-occupational/unknown source of lead absorption as Māori. European/Other ethnic group had the highest reported non-occupational/unknown lead absorption notification rate (1.7 per 100,000; 372 notifications), followed by Pacific Peoples (1.3 per 100,000; 28 notifications). However, 20% of the notifications listed ethnicity as ‘unknown’ (Table 2).
Table 2: Non-occupational/unknown source of lead absorption notifications and rates, by prioritised ethnic group, 2014–20
Lead-based paint remained the most common source of non-occupational lead exposure since 2014
In 2020, there were 62 non-occupational/unknown lead absorption notifications. Since 2014, the most common sources of non-occupational lead exposure were lead-based paint, indoor rifle range and bullet/sinker manufacture (Table 3). Sixteen notifications had an unknown lead source in 2020. Other common non-occupational sources identified in 2014–20 were pica, gunshot wound, bullet/sinker manufacture and traditional medicines or cosmetics.
Table 3: Number of non-occupational or unknown lead absorption notifications, 2014–20
Identifying people with potential lead exposure can be challenging, especially through recreational activities or hobbies, where signs and symptoms do not appear until dangerous amounts have accumulated (BPAC 2021). However, the primary source of lead exposure, especially for young children, is in their home. In 2020, there were four lead exposure notifications involving children aged under 15 years. Three of them had pica and had lead contamination in their homes.
People exposed to lead-based cosmetics or traditional medicines have relatively higher blood lead levels
In 2014–20, among those who were notified, people exposed to lead-based cosmetics or traditional medicines (eg, Ayurvedic remedies) had relatively higher blood lead levels compared to other sources of non-occupational/unknown source of exposures (Table 4).
Table 4: Median blood lead level, interquartile range by non-occupational/unknown source of exposures and number of notifications, 2014–20
Wairarapa DHB and Taranaki DHB Public Health had the highest reported rate of non-occupational/unknown lead absorption
In 2014–20, the Wairarapa DHB (6.5 per 100,000; 21 notifications) and Taranaki DHB Public Health Unit (4.6 per 100,000; 39 notifications) had the highest reported rate of non-occupational/unknown source of lead absorption among DHBs and PHUs respectively (Table 5).
Table 5:Non-occupational/unknown source of lead absorption notification rate and number of notifications, by DHB and PHU, 2014–20
Information about the data
This indicator reports HSDIRT non-occupational/unknown source of lead absorption 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.
Repeat blood lead tests taken within a year of the original test have been excluded from this data unless further investigation has resulted.
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.Armstrong R, Anderson L, Synnot A, et al. 2014. Evaluation of evidence related to exposure to lead. Canberra: National Health and Medical Research Council. URL: www.nhmrc.gov.au/guidelines-publications/eh58 (accessed 13 October 2021).
2.BPAC. 2021. Lead absorption notification levels have reduced. Occupational medicine: Public Health URL: https://bpac.org.nz/2021/lead.aspx (Accessed 8 September 2021)
3.Centers for Disease Control and Prevention. 2017. Pica behaviour and Contaminated Soil. URL: http://medbox.iiab.me/modules/en-cdc/www.cdc.gov/healthcommunication/toolstemplates/entertainmented/tips/Pica.html (Accessed August 2021).
4.Reuben A, Schaefer JD, Moffitt TE, et al. 2019. Association of childhood lead exposure with adult personality traits and lifelong mental health. JAMA psychiatry, 76(4), 418-425.
5.World Health Organization. 2020. Lead poisoning and health, URL: https://www.who.int/news-room/fact-sheets/detail/ lead-poisoning-and-health (accessed 13 October 2021).