Air quality & human development · 2022

Does a higher quality of life mean cleaner air?

Mostly yes, for the air people breathe. As countries develop, fine-particle pollution falls steadily, from about 38.5 µg/m³ in the least-developed countries to roughly 10.2 in the most developed. The pollution they emit per person tells a more complicated story.

Air-quality pollutants, meaning sulfur dioxide (SO₂), nitrogen oxides (NOₓ) and the fine particles (PM2.5) they form, harm health directly, unlike greenhouse gases. This page looks at how both the pollution countries emit and the pollution people breathe change with the Human Development Index. For the climate side, see carbon emissions per unit of human development.

Sources: Yale Environmental Performance Index 2024 (SO₂, NOₓ, PM2.5, HDI); Energy Institute Statistical Review of World Energy. Data year 2022. Site updated August 13, 2026.

Key facts · 2022

Cleanest air, high developmentSwitzerland
  · SO₂+NOₓ per person5.9 kg
Most polluting, high developmentKuwait
  · SO₂+NOₓ per person169.0 kg
PM2.5: least vs most developed38.5 → 10.2 µg/m³
High-HDI countries ranked52

Two different stories: emissions vs. exposure

Greenhouse gases and air pollutants behave differently as countries get richer. The air people breathe (PM2.5) tends to get cleaner with development, because wealthy countries fit scrubbers, catalytic converters and cleaner fuels. But the pollution a country emits per person often rises through industrialisation before falling again at the top, the classic “environmental Kuznets curve.” A country can also emit a lot yet have clean air if its pollution disperses (Australia), or emit and breathe badly at once (the Gulf states).

The air people breathe vs. development

Each point is a country: quality of life (HDI) on the horizontal axis, the fine-particle pollution people are exposed to (PM2.5) on the vertical. Exposure falls as development rises.

HDI vs. PM2.5 exposure, 2022

101 countries · WHO guideline is 5 µg/m³ · hover for names

The pollution countries emit: an inverted-U

Median sulfur dioxide and nitrogen oxide emissions per person rise through industrialisation, then fall in the most developed economies, even as the air people breathe keeps improving.

Emissions vs. exposure across development, 2022

Median by HDI band

Air pollution among high-development countries

Kilograms of SO₂ and NOₓ emitted per person, 2022, for the 52 countries of very high human development (HDI ≥ 0.8). Lower is cleaner. Click a column to sort.

Country SO₂+NOₓ per person (kg) SO₂ NOₓ PM2.5 (µg/m³) HDI
Switzerland5.90.45.510.20.967
Italy10.11.38.816.30.906
Netherlands10.31.29.19.60.946
Hungary10.81.39.414.00.851
United Kingdom10.91.89.110.00.940
Sweden11.41.59.85.60.952
Germany12.13.19.19.60.950
Slovakia12.12.69.613.80.855
France12.71.711.010.50.910
Slovenia12.81.811.013.90.926
Belgium13.12.011.010.10.942
Croatia13.11.611.516.50.878
Austria13.31.212.110.70.926
Denmark13.81.512.48.20.952
Romania13.93.710.217.00.827
Spain14.72.811.912.00.911
Portugal15.23.511.79.40.874
Ireland15.91.914.08.10.950
Cyprus16.68.28.520.60.907
Japan16.84.112.712.20.920
South Korea18.03.614.423.30.929
Latvia19.02.017.013.70.879
Czech Republic20.66.813.812.80.895
Finland22.24.417.85.00.942
Poland23.89.913.915.90.881
Thailand23.88.015.823.50.803
Lithuania23.96.717.111.10.879
Belarus24.68.216.411.40.801
United States25.45.020.37.50.927
Estonia26.110.016.16.60.899
Greece26.28.118.116.20.893
Argentina28.32.625.715.40.849
Hong Kong28.58.520.016.30.956
Norway35.32.932.55.60.966
Singapore40.020.819.115.00.949
Trinidad & Tobago42.313.728.614.20.814
Chile42.420.821.528.20.860
Malaysia42.617.924.715.20.807
Turkiye44.634.99.726.90.855
New Zealand47.512.634.96.90.939
Canada50.215.934.36.30.935
Oman51.014.736.450.50.819
Israel56.916.940.022.50.915
Russia66.436.330.111.70.821
Australia77.739.937.85.30.946
Bahrain78.942.436.560.40.888
Kazakhstan100.954.047.017.70.802
Serbia108.695.013.619.90.805
United Arab Emirates113.155.058.165.50.937
Qatar140.971.369.6108.20.875
Saudi Arabia159.793.366.476.10.875
Kuwait169.0100.868.268.50.847

Per-person emissions of SO₂ and NOₓ from the Yale EPI; PM2.5 is the population-weighted concentration people breathe. Some high-emitting countries (Australia, for example) still have low PM2.5 because pollution disperses; others rank badly on both.

Frequently asked questions

Do richer countries have cleaner air?

Largely yes for the air people breathe. Median PM2.5 exposure falls from about 38.5 µg/m³ in the least-developed countries to roughly 10.2 in the most developed, as wealthier nations adopt scrubbers, cleaner fuels and emission standards.

Which developed country has the cleanest air pollution record?

Among very-high-development countries in 2022, Switzerland emits the least, about 5.9 kg of SO₂ and NOₓ per person. Switzerland, the Netherlands, the UK and Sweden lead the group.

Which developed countries emit the most air pollution per person?

Oil- and gas-rich states top the list: Kuwait emits about 169.0 kg of SO₂ and NOₓ per person, with Saudi Arabia, Qatar and the UAE close behind, and their populations also breathe some of the world's highest PM2.5 levels.

What is the environmental Kuznets curve?

The idea that pollution rises during early industrialisation, then falls once a country is rich enough to invest in cleaner technology and demand better air. SO₂ and NOₓ emissions per person follow this inverted-U; per-person carbon emissions are far less likely to.

Can a country emit a lot of air pollution but still have clean air?

Yes. Australia emits a lot of SO₂ and NOₓ per person but has very low PM2.5 exposure because emissions disperse over a large, sparsely populated area. The air pollution people breathe depends on where and how densely it is emitted, not just the national total.

Related pages

Sources: Yale Environmental Performance Index 2024 (SO₂, NOₓ, PM2.5, HDI). See methodology.