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 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

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

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

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

Figure 4: Air pollution sources in New Zealand (Source Ministry for the Environment)

Air pollution can vary across the r