WHO research shows majority of people breathe harmful air

Almost every person on the planet is exposed to air pollution that exceeds safe limits, the World Health Organization warned as it launched a new air quality database.

Ninety-nine per cent of people breathed in air that sometimes or always exceeded harmful levels, the health body said on Monday as it highlighted the urgent need to curb pollution caused mainly by burning fossil fuels.

“It is unacceptable to still have 7mn preventable deaths and countless preventable lost years of good health due to air pollution,” said Maria Neira, WHO director of environment, climate change and health. “Too many investments are still being sunk into a polluted environment rather than in clean, healthy air.”

The WHO has tightened its guidelines for healthy levels of the most hazardous pollutants, nitrogen dioxide (NO2) and fine particulates with diameters of less than 10 microns (PM10) or 2.5 microns (PM2.5), in response to growing evidence of the damage they cause to human health.

People living in low and middle-income countries suffered the most exposure to PM10 and PM2.5 pollutants, but air pollution shortened lives even in wealthier regions, said Neira, adding that it caused an estimated 400,000 deaths a year in Europe alone.

In the eastern Mediterranean region and south-east Asia, average PM10 levels are six to eight times above safe levels, with particularly high readings recorded when fine desert dust supplements man-made pollution.

Fewer than 1 per cent of cities in low and middle-income countries comply with WHO guidelines for PM10 and PM2.5 particles, which can penetrate deep into the lungs and enter the bloodstream, potentially causing heart and brain disease.

“They can damage almost every organ in our body,” said Neira.

Patterns of NO2 pollution show a different pattern, with wealthier countries suffering almost as much as their poorer counterparts. NO2 is associated with respiratory diseases, especially asthma, leading to breathing problems that may require hospital admission.

The WHO insisted it did not want to create a league table that highlighted the place with the dirtiest air after about 6,000 towns and cities around the world contributed to its database.

But the data show New Delhi in India and Dhaka in Bangladesh had particularly bad PM10 pollution, with average annual levels that were more than 10 times higher than WHO recommended levels. Mexico City stood out for NO2 pollution, with an average that was eight times higher than the safe limit.

The drive to improve air quality meshes with the broader battle against climate change, said WHO director-general Tedros Adhanom Ghebreyesus.

“High fossil fuel prices, energy security and the urgency of addressing the twin health challenges of air pollution and climate change underscore the pressing need to move faster towards a world that is much less dependent on fossil fuels,” he added.