The Burrow
Apr 22, 2026
With pollution a major concern in recent years, air quality is more important than ever. Pollution can come from car exhaust on busy highways and harmful gases from different factory operations. Although some air pollution can’t be seen with the naked eye, the air we breathe every day can be full of chemicals, many of which can have harmful effects.
Clean air isn’t only essential for humans but also for the environment, as plants and animals need it to survive. Polluted air exposure has been related to health concerns, including cancer, cardiovascular disease, respiratory diseases, diabetes mellitus, obesity, and reproductive, neurological, and immune system disorders.1
To explore which regions have the cleanest air quality and have been less? impacted by respiratory issues, the health insurance comparison experts at Compare the Market created the global air quality and respiratory health rankings to reveal which parts of the world are the least polluted and have reported fewer respiratory health issues. We analysed all states and territories in Australia, and the US, along with reviewing countries on a global scale, scoring each area and country from 0 to 100 in the overall index.
Our air quality and respiratory health Index ranks each state and territory in Australia using factors including the number of respiratory diseases per 100k residents, the prevalence of asthma in the region, the number of industrial toxins produced, and PM2.5 pollution levels (fine air pollutant particulate matter with a diameter of 2.5 micrometres). The higher the score, the cleaner the region’s air is. Here are the highest-scoring Australian regions:
| Australian state or territory | Fine pollution PM2.5 (µg/m³) | Industrial pollutant substances emitted | Asthma prevalence (%) | Respiratory diseases per 100k | Air quality and respiratory health score |
|---|---|---|---|---|---|
| Northern Territory | 11.70 | 65 | 7.8 | 14,620 | 65.00 |
| New South Wales | 6.32 | 72 | 8.9 | 28,010 | 55.63 |
| Australian Capital Territory | 6.60 | 57 | 11.5 | 37,710 | 50.13 |
| South Australia | 4.72 | 65 | 11.8 | 33,850 | 49.57 |
| Tasmania | 5.23 | 64 | 12.7 | 34,710 | 43.65 |
| Western Australia | 7.19 | 73 | 9.7 | 31,430 | 43.64 |
| Queensland | 6.30 | 75 | 11.4 | 26,690 | 41.13 |
| Victoria | 6.03 | 77 | 12.9 | 35,910 | 22.26 |
The Northern Territory was ranked first in our air quality and respiratory health Index for Australia. It had the lowest asthma rates in the country (7.8%), and the fewest respiratory disease cases per capita, with 14,620 cases per 100k residents. However, the NT had the highest PM2.5 pollution level of 11.7 µg/m³, which is the highest in Australia. Despite this, its overall score of 65.00 out of 100 was the best in the country.
New South Wales was ranked second in our air quality and respiratory health index, with a score of 55.63 out of 100 overall. It scored well across the board, with the third-fewest respiratory diseases per 100k residents (28,010), the second-lowest asthma prevalence (8.9%), and just 6.32 PM2.5 particles per µg/m³.
The Australian Capital Territory was ranked third and had the fewest industrial pollutants emitted in Australia, with just 57 recorded by the National Pollutant Inventory. Despite this, the ACT reported the highest incidence of respiratory diseases in the country (37,710 per 100k residents), paired with one of the higher rates of 11.5% of residents with asthma. It also reported one of the higher PM2.5 pollution rates (6.6 µg/m³) and an overall score of 50.13 out of 100.
South Australia was ranked fourth in Australia’s air quality and respiratory health index and can take pride in having the lowest PM2.5 pollution level (4.72 µg/m³) in the nation. Despite having the third-highest asthma rate in the country (11.8%), it had a moderate amount of industrial toxins emitted (65) in comparison to the rest of Australia. All of these contribute to its score of 49.57 out of 100.
Finally, Tasmania completes the top five for Australia’s air quality and respiratory health index with a score of 43.65 out of 100. The state’s PM2.5 pollution level was the second lowest in Australia (5.23), alongside the second lowest industrial toxins (64) recorded by the NPI. However, Tasmania reported the second-highest asthma prevalence in the country (12.7%).
Now that we’ve looked at Australia’s results, let’s take a trip across the ocean to see how the US fares in comparison. The factors used in the United States Clean Air Index included industrial toxins (pounds per square mile), asthma prevalence, respiratory deaths (per 100k of the population) and PM2.5 pollution levels (fine air pollutant particulate matter with a diameter of 2.5 micrometres). These are the five US states with the highest rankings on our clean air list:
| United States | Fine air pollution PM2.5 (µg/m³) | Industrial toxins (lbs per sq mile) | Asthma prevalence (%) | Respiratory deaths (per 100k) | Air quality and respiratory health score |
|---|---|---|---|---|---|
| Hawaii | 4.30 | 402 | 9.1 | 15.2 | 91.81 |
| South Dakota | 5.90 | 114 | 8.3 | 36.1 | 81.07 |
| Nebraska | 6.20 | 221 | 8.1 | 41.9 | 77.04 |
| New York | 6.90 | 351 | 10.3 | 21.2 | 75.50 |
| New Jersey | 7.40 | 1,499 | 8.9 | 20 | 72.78 |
With a score of 91.81 out of 100, Hawaii dominates the US air quality and respiratory health index. It boasts the lowest PM2.5 pollution level in the country (4.3 µg/m³) and the fewest respiratory disease-related deaths per 100k residents (15.2). The state also ranks relatively low for asthma prevalence (9.1%) alongside fairly low industrial toxin levels (402 lbs/sq mile).
Only two states in the US have fewer toxic pollutants than South Dakota’s 114 industrial toxins per sq mile (Vermont and New Hampshire), which is paired with one of the lower PM2.5 pollution levels (5.9 µg/m³). Despite a high rate of respiratory deaths (36.1 per 100k people), its low asthma prevalence of 8.3% helped drive South Dakota’s total score of 81.07 out of 100 in the US air quality and respiratory health index.
Only 8.1% of Nebraskans have asthma, which is the second-lowest prevalence of the condition in the US (Texas had the lowest with 7.9%). Although it records 41.9 deaths per 100k people due to respiratory issues, its PM2.5 pollution level stands fairly low (6.2 µg/m³), with moderate toxin levels of 221 lb/sq mile. These factors combined ranked Nebraska third with an overall score of 77.04 out of 100 in our US air quality and respiratory health index.
Big cities are typically associated with poor air quality, but surprisingly, New York was ranks fourth, given it’s the home of the most populous city in the US. However, at a state level, it scored well in our air quality and respiratory health index, earning a score of 75.50 out of 100. It has just 21.2 respiratory deaths reported per 100k residents, and an average PM2.5 pollution level of 6.9 µg/m³. Plus, its 351 lbs/sq mile of toxins is much lower than in other highly populated states, including Illinois (1,088) and Pennsylvania (1,277).
New Jersey ranks fifth in our air quality and respiratory health index, despite its high toxin levels of 1,499 lbs/sq mile. It reported a low asthma rate of 8.9%, and only 20 respiratory deaths per 100k residents, scoring 72.78 out of 100 overall, outscoring states Maryland (72.63), Minnesota (72.61), and Florida (70.12) to round out our rankings.
Now we’ve examined where in Australia and America has good air quality, what about globally? We analysed 88 countries worldwide using factors such as greenhouse gas emissions (CO2), asthma rates, respiratory deaths and PM2.5 pollution levels to find out which countries boast clean air and few respiratory issues on a global scale.
| Global country | Greenhouse gas emissions (t CO₂e) | Fine air pollution PM2.5 (µg/m³) | Asthma rate (per 100k) | Respiratory deaths (per 100k) | Air quality and respiratory health score |
|---|---|---|---|---|---|
| Estonia | 14,360,000 | 4.7 | 3,442.19 | 9.30 | 94.17 |
| Latvia | 10,960,000 | 8.0 | 3,783.45 | 7.19 | 93.12 |
| Lithuania | 20,680,000 | 10.4 | 3,214.88 | 7.60 | 92.77 |
| Albania | 7,670,000 | 16.7 | 3,879.33 | 6.81 | 88.89 |
| Moldova | 13,540,000 | 15.7 | 3,425.39 | 9.86 | 88.48 |
With a staggering score of 94.17 out of 100, Estonia scored the highest in our global air quality and respiratory health index. The country records just 3,442.19 asthma cases per 100k residents and only 9.3 respiratory deaths in the same sample size. Plus, Estonia’s PM2.5 pollution rates of only 4.7 µg/m³ are among the lowest in the world.
Just across the border, Latvia ranked second in our global air quality and respiratory health index, with an average PM2.5 concentration of only 8 µg/m³. The country emitted 10.96 million tons of greenhouse gas in 2023, which sounds like a lot, but is much lower than most other countries in the index! Plus, it reported only 7.19 respiratory deaths and 3,783.45 asthma cases per 100k residents. These add up to a total score of 93.12 out of 100.
Continuing with Baltic countries at the top of our global air quality and respiratory health index, Lithuania boasts an index score of 92.77 out of 100. It reported a low asthma rate of just 3,214.88 cases per 100k people, which played a role in its high rank, but it also has low PM2.5 pollution levels (10.4 µg/m³) and few respiratory disease-related deaths (7.6 per 100k residents).
Of all the countries in our top five, Albania has the lowest greenhouse gas emissions, with 7.67 million tons of CO₂ equivalent released in 2023. It also has a low number of respiratory deaths (6.81 per 100k), although its PM2.5 pollution level of 16.7 µg/m³ is higher than that of many other European countries. Still, with a total score of 88.89 out of 100, it’s ranked fourth-place in our global air quality and respiratory health index .
Scoring 88.48 out of 100, Moldova rounds out our top five countries in our global air quality and respiratory health index, just beating Ukraine (88.00) and Slovakia (87.86). This was reflected in the health indicators with 3,425.39 asthma cases reported and 9.86 respiratory deaths per 100k of residents. The country produces approximately 13.54 million tonnes of CO₂e, placing it in the mid‑range among peers in terms of greenhouse gas emissions.
Steven Spicer, Executive General Manager of Health at Compare the Market, comments: “Clean air plays a vital role in protecting our health, as long-term exposure can be linked to respiratory diseases, causing illnesses and impacting overall health. Having reliable private health insurance could be valuable, as it may help support access to medical care, early treatment, and ongoing management of any related conditions.”
This dataset ranks US states, Australian states and territories, and 88 countries globally based on air quality and respiratory health outcomes.
By combining air pollution indicators with health metrics linked to respiratory illness, the index highlights regions with cleaner air and stronger respiratory health outcomes.
Three separate indices were produced:
Each metric was normalised to a score between 0 and 1. If data was missing, a score of 0 was assigned. The scores were then averaged across all metrics to produce a total score out of 100, with regions ranked from highest to lowest. Higher scores indicate cleaner air and stronger respiratory health outcomes.
Australian Index
The Australian index ranks states and territories using air pollution indicators and respiratory health metrics.
Factors used
United States Index
The US index ranks states using air pollution indicators and respiratory health metrics.
Factors used
Global Index
The global index ranks selected countries based on pollution exposure and respiratory health outcomes. Countries were included based on data availability.
Factors used
Lower values across all of these metrics indicate better environmental and respiratory health conditions.
Sources: