Air pollution threatens the health of 7.9 million people across 39 districts in Washington. The average PM2.5 level is 5.2 µg/m³—1.0× higher than the WHO guideline.
Brought to you by Amrit Sharma
Washington faces significant air pollution challenges. 41% of districts exceed the WHO guideline for clean air. This is putting 7.9 million across 39 districts at risk.
The average PM2.5 over 2023 was 5.2µg/m³. That's 1.0 times the WHO guideline for clean air of 5µg/m³.
This is equivalent of everybody, including children, smoking about 86 cigarettes in a year.
If Washington met the WHO guideline of 5 µg/m³, the average person would live 0.03 years longer.
That's 236K years of life stolen from 7.9 million people. Years of watching children grow up. Years of building a career. Years of quiet mornings and celebrations.
Lives cut short. Breathing kills.
The top 10 most polluted districts in Washington. These areas face the greatest health burden from air pollution.
Distribution of population across different PM2.5 pollution levels. The WHO guideline is 5 µg/m³—only populations below this threshold are breathing safe air.
Complete air quality data for every district in Washington, sorted by population.
| District | Population | PM2.5 µg/m³ | Years Lost |
|---|---|---|---|
| King | 2.5M | 5.4 | 0.0 years |
| Pierce | 907K | 4.8 | 0.0 years |
| Snohomish | 792K | 4.4 | 0.0 years |
| Spokane | 571K | 6.9 | 0.2 years |
| Clark | 482K | 5.2 | 0.0 years |
| Thurston | 296K | 4.0 | 0.0 years |
| Yakima | 264K | 6.5 | 0.1 years |
| Kitsap | 251K | 4.6 | 0.0 years |
| Whatcom | 230K | 4.7 | 0.0 years |
| Benton | 216K | 5.8 | 0.1 years |
| Skagit | 130K | 4.2 | 0.0 years |
| Cowlitz | 112K | 3.9 | 0.0 years |
| Grant | 102K | 5.2 | 0.0 years |
| Franklin | 100K | 5.7 | 0.1 years |
| Lewis | 85K | 3.6 | 0.0 years |
| Chelan | 83K | 6.8 | 0.2 years |
| Clallam | 78K | 4.5 | 0.0 years |
| Grays Harbor | 77K | 3.6 | 0.0 years |
| Island | 74K | 3.6 | 0.0 years |
| Walla Walla | 66K | 5.5 | 0.1 years |
| Mason | 62K | 4.7 | 0.0 years |
| Whitman | 51K | 4.5 | 0.0 years |
| Okanogan | 45K | 8.6 | 0.3 years |
| Kittitas | 44K | 5.2 | 0.0 years |
| Stevens | 44K | 7.1 | 0.2 years |
| Douglas | 40K | 6.6 | 0.2 years |
| Jefferson | 30K | 3.9 | 0.0 years |
| Pacific | 23K | 3.0 | 0.0 years |
| Klickitat | 22K | 4.3 | 0.0 years |
| Asotin | 21K | 6.5 | 0.2 years |
| Adams | 21K | 4.7 | 0.0 years |
| San Juan | 16K | 4.1 | 0.0 years |
| Pend Oreille | 13K | 7.0 | 0.2 years |
| Lincoln | 10K | 4.8 | 0.0 years |
| Skamania | 10K | 4.4 | 0.0 years |
| Ferry | 7K | 7.2 | 0.2 years |
| Columbia | 4K | 4.8 | 0.0 years |
| Wahkiakum | 4K | 3.3 | 0.0 years |
| Garfield | 2K | 4.5 | 0.0 years |
Showing 39 districts, sorted by population (largest first). PM2.5 values are for 2023. Years lost calculated against WHO guideline of 5 µg/m³.