New WHO Global Air Quality Guidelines calls for lower limits on air pollution to save millions of lives

Millions of deaths could be avoided if the world adopts tough new air pollution limits set out by the World Health Organization (WHO).

The new Global Air Quality Guidelines calls for much lower daily and annual levels of exposure to six pollutants - particulate matter (PM₁₀ and PM₂.₅), ozone (O₃), nitrogen dioxide (NO₂) sulphur dioxide (SO₂) and carbon monoxide (CO).

The guidelines have been reviewed for first time since 2005 after five years of systematic review of more than 500 research papers and including several rounds of peer review. On the basis of this evidence it concluded that air pollution was harmful to health at lower concentrations and produced a wider range of damage than was previously thought.

Seven million deaths a year are attributed to air pollution, and hundreds of millions of years of healthy life are lost, WHO said, this makes burden of disease attributable to air pollution on a par with other major global health risks such as unhealthy diet and tobacco smoking. 

At the focus of campaigning efforts is particulate matter equal or smaller than 10 and 2.5 microns (µm) in diameter (PM₁₀and PM₂.₅, respectively) as health risks associated with are of particular public health relevance. Both PM₂.₅ and PM₁₀ are capable of penetrating deep into the lungs but PM₂.₅ can even enter the bloodstream, primarily resulting in cardiovascular and respiratory impacts, and also affecting other organs.

Under the new advice, annual limits on people’s exposure to PM₂.₅ are halved and annual exposure to nitrogen dioxide is cut by 75 per cent. A summary of the new limits is shown below.

Though not legally binding, the new rules offer a guide to governments across the world looking to reduce the impact of air pollution on their citizens. Meeting the new limits will require leaders to take tougher action against fossil fuel burning, heavy vehicle traffic and highly polluting industries.

 

Pollutant

Averaging Time

2005 AQGs

2021 AQG

PM2.5,μg/m3

Annual

10

5

24-hour

25

15

PM10, μg/m3

Annual

20

15

24-hour

50

45

O3, μg/m3

Peak Season

-

60

8-hour

100

100

NO2, μg/m3

Annual

40

10

24-hour

-

25

SO2, μg/m3

24-hour

20

40

CO, mg/m3

24-hour

-

4

 

REHIS is a registered charity in Scotland, SC009406

Web design by Peacock Carter Ltd