# WHO tightened global air quality guidelines, cutting annual PM2.5 target to 5 µg/m³

Date: 2021

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## Drivers

- Air Pollution: https://factrail.ai/drivers/air-pollution

## Sources

_Sources are listed on the canonical page._

## Methodology

https://factrail.ai/methodology

Canonical: https://factrail.ai/facts/who-global-air-quality-guidelines-2021