WHO updates Air Quality Guidelines


The World Health Organization (WHO) has revised its 2005 Global Air Quality Guidelines (AQGs) to decrease the burden of disease that results from exposure to air pollution worldwide.

The updated guidelines provide recommendations on air quality guideline levels as well as interim targets for six key air pollutants.

Whilst not legally-binding, like all WHO guidelines, AQGs are an evidence-informed tool for policy-makers to guide legislation and policies to reduce levels of air pollutants.

WHO Regional Director for Europe, Dr Hans Henri P. Kluge, commented on the announcement: “Annually, WHO estimates that millions of deaths are caused by the effects of air pollution, mainly from noncommunicable diseases.

“Clean air should be a fundamental human right and a necessary condition for healthy and productive societies. However, despite some improvements in air quality over the past three decades, millions of people continue to die prematurely, often affecting the most vulnerable and marginalized populations.

“We know the magnitude of the problem and we know how to solve it. These updated guidelines give policy-makers solid evidence and the necessary tool to tackle this long-term health burden.”

The guidelines focus on so-called classical pollutants, particulate matter (PM₂.₅ and PM₁₀), ozone (O₃), nitrogen dioxide (NO₂), sulfur dioxide (SO₂) and carbon monoxide (CO).

According to WHO, PM is primarily generated by fuel combustion in different sectors, including transport, energy, households, industry, and from agriculture.

Solutions to improve air quality include investing in energy-efficient power generation, providing universal access to clean, affordable fuels and technologies for cooking, heating and lighting, as well as building safe and affordable public transport systems and pedestrian- and cycle-friendly networks.

Every year, exposure to air pollution is estimated to cause 7 million premature deaths and result in the loss of millions more healthy years of life.

According to WHO, the health risks associated with particulate matter equal or smaller than 10 and 2.5 microns (µm) in diameter (PM₁₀ and PM₂.₅, respectively) 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 affecting other organs.

According to WHO, almost 80% of deaths related to PM₂.₅ could be avoided in the world if the current air pollution levels were reduced to those proposed in the updated guideline.

In 2019, more than 90% of the global population lived in areas where concentrations exceeded the 2005 WHO air quality guideline for long term exposure to PM₂.

A recent analysis by City Hall found that 3.1m English children are attending schools in areas exceeding WHO limits for PM₂.₅.

According to this analysis, the poor air quality stunts the growth of children’s lungs and worsens chronic illnesses, such as asthma, lung and heart disease.

More information about the updated air quality guidelines is available on the World Health Organization website.