Air quality in the Auckland region
Having clean air is essential for good health.
Auckland’s outdoor air quality (also called 'ambient air quality') meets New Zealand and international standards and guidelines in most places and most times of year, and is better than many cities of similar size.
Auckland’s air quality has improved over the last 20 years, but there are areas where air pollution causes problems and pollution sources that could be improved. The city’s growth and transport system will continue to put pressure on our air quality. Around the world, air pollution is a major cause of illness and early death.
Auckland’s air quality is monitored by Auckland Council. Auckland’s Air Quality Report Card 2016 found that our air quality is generally good, and identifies the main sources of air pollution in Auckland as (1) transport; and (2) home heating in winter (mostly from wood burners). Our air quality is worse in winter than summer.
Figure 1: Air quality measures in Auckland 2005 – 2015 (Source: Auckland Council: Air Quality Report Card 2016)
Every four years Statistics New Zealand and the Ministry for the Environment produce a major report on air quality across the country. Key findings in the 2018 report, Our Air, include that air quality is improving over time in most places; burning wood and coal for home heating is the largest human-made source of fine particles in outdoor air pollution that causes most harm; and that there are a number of areas, especially around major roads, industrial areas and ports, where air pollution is of concern.
Air pollution affects our health in several ways, by increasing asthma and bronchitis, heart disease and stroke, and other conditions like diabetes. The effects that are specific to the lungs and heart happen because the extremely small particles can get into the bloodstream, and can cause chronic inflammation.
Even though Auckland’s air quality is relatively good, estimates based on international research indicate that about 430 adults died prematurely in Auckland from air pollution in 2016, compared with about 320 in 2006. The increase is mainly due to population increase even though the rate of deaths has decreased.
Figure 2: Health effects of particles (Source: Ministry for the Environment)
The main outdoor air pollutants that affect people’s health include:
- Fine particles – called PM10 and PM2.5.
- Gases, including oxides of nitrogen, sulphur dioxide, ozone and carbon monoxide
- Other hazardous pollutants, including metal particles like arsenic
Fine particulate material (PM), which is smaller than 10 micrometres (PM10) or 2.5 micrometres (PM2.5), gets into the lungs and causes or worsens respiratory illness (such as asthma and bronchitis) and heart disease. The smallest particles have the worst effects on our health.
Figure 3: Air pollution particle sizes. Source Ministry for the Environment 2014
Polluting gases include oxides of nitrogen, (NOx), sulphur dioxide (SO2), carbon monoxide (CO) and ozone (O3). These come directly from burning fuels, or indirectly from chemical reactions in the air involving other pollutants.
Other hazardous air pollutants include arsenic (from burning treated timber), lead (from burning old painted wood) and organic compounds from incomplete burning of fuel or fires.
Follow this link for more information on how air pollution affects health.
This diagram shows the main sources of air pollution. In Auckland the main sources of air pollution are vehicles (all year), and fires and wood burners for home heating (in winter). These affect air quality across the whole city. Air pollution from fine particles increases in winter by more than 10 tonnes a day, more than trebling air pollution.
Figure 4: Air pollution sources in New Zealand (Source Ministry for the Environment)
Air pollution can vary across the region. Some types of air pollution (such as PM) affect air quality across the whole city. Some types of pollution from vehicles (such as NOx) are worse near busy roads and in the central city (where tall buildings create a canyon where air doesn’t move much). Services such as childcare centres and residential care centres near busy roads can be noticeably affected by air pollution. Some places require childcare centres and other residential care centres to be away from busy roads and industrial air pollution sources, but in Auckland there are few such restrictions.
The Auckland Port is a source of SO2 and PM pollution from ships’ engines.
Local air pollution sources can have serious effects on health. Burning old timber, for example, can release arsenic (from tanalised timber) and lead (from old painted timber) into the local air.
People spend most of their time indoors, so indoor air quality needs to be considered too.
The most important indoor air pollution is tobacco smoke. ARPHS supports smokefree environments at home, especially where there are children.
Portable and free-standing gas heaters (called 'unflued' gas heaters) release air pollutants – including oxides of nitrogen and carbon dioxide – and moisture inside your house, increasing illness from air pollution, and encouraging growth of mould. The best thing to do is get rid of these heaters and replace them with electric heaters or heat pumps.
Domestic fires and wood burners are an important source of indoor and outdoor air pollution. If your house has an open fire or old wood burner, we recommend replacing it with a heat pump, new wood burner or other efficient heating. Open fires and old wood burners might look great, but they’re not good for you.
There are many other potential sources of indoor air pollution, including some building products, some furnishing fabrics, adhesives, solvents, cleaning products and chemicals used at home. If these materials are used inside, ensure the house is well ventilated.
Auckland Council monitors air quality, sets local air quality targets, controls air discharges through the Unitary Plan and resource consents, and responds to air pollution incidents.
NIWA carries out air quality research to improve our understanding of air quality and air pollution in urban areas such as Auckland.
Auckland Regional Public Health Service provides a supporting role to Auckland Council, assists with assessing air pollution sources and resource consent applications, and responds to complaints.
- Air quality report card, Auckland area 2018 (Auckland Council Research and Evaluation Unit)
- Environmental reporting (Ministry for the Environment)
- Ambient (outdoor) air quality and health (World Health Organisation)
- Air quality: Interactive site on air pollution in New Zealand (Land Air Water Aotearoa)
- Air quality (NIWA)
- Carbon monoxide poisoning (Centre for Disease Control and Prevention)
Last updated 13.3.2024