The World Health Organization (WHO) has strengthened its air quality guidelines, or AQGs, as it warned that air pollution was one of the biggest environmental threats to human health, causing seven million premature deaths a year.
The United Nations health agency said on Wednesday that urgent action was needed to reduce exposure to air pollution, ranking its burden of disease “on a par with other major global health risks such as unhealthy diet and tobacco smoking”.
The WHO said the burden of disease attributable to air pollution was
“WHO has adjusted almost all the air quality guideline levels downwards, warning that exceeding the new … levels is associated with significant risks to health,” it said. “Adhering to them could save millions of lives.”
The new guidelines aim to protect people from the adverse effects of air pollution and are used by governments as a reference for legally binding standards.
The WHO last issued AQGs in 2005, which had a significant impact on pollution abatement policies worldwide.
However, the WHO said in the 16 years since, a much stronger body of evidence had emerged, showing how air pollution affects health at lower concentrations than previously understood.
“The accumulated evidence is sufficient to justify actions to reduce population exposure to key air pollutants, not only in particular countries or regions but on a global scale,” the organisation said.
Southeast Asia worst hit
The WHO’s new guidelines include recommendations for air quality levels for six pollutants, including ozone, nitrogen dioxide, sulphur dioxide and carbon monoxide.
The other two are PM10 and PM2.5 – particulate matter equal or smaller than 10 and 2.5 microns in diameter.
Both are capable of penetrating deep into the lungs but research shows PM2.5 can even enter the bloodstream, primarily resulting in cardiovascular and respiratory problems, but also affecting other organs, said the WHO.
In response, the PM2.5 guideline level has been halved.