Millions of lives around the world could be saved if countries commit to tougher air pollution targets, the World Health Organization has said.
The global health body has set new guidelines for air quality, with the recommended safe level of pollutants now half what it was when the standards were last reviewed in 2005.
Since then, the WHO said, there has been a slew of evidence showing the dangers of air pollution, which is linked to around seven million premature deaths a year.
The new guidelines recommend air quality levels for six pollutants – particulate matter (PM), ozone, nitrogen dioxide, sulfur dioxide and carbon monoxide – that come from a range of sources such as transport, energy, agriculture and burning of wood and fossil fuels.
However, reducing the level of PM to less than 10 and 2.5 microns in diameter could have the biggest impact on health, the WHO said. Both PM2.5 and PM10 can penetrate deep into the lungs but PM2.5 can enter the bloodstream, resulting in cardiovascular and respiratory disease.
Dr Tedros Adhanom Ghebreysus said air pollution was a threat everywhere but the burden is greatest in low and middle income countries.
"Air pollution is a health threat in all countries, but especially for vulnerable groups in low and middle income countries with poor air quality due to urbanisation and rapid economic development as well as pollution in the home caused by cooking, heating and lighting," he said.
"I urge all countries and all those fighting to protect our environment to put [the guidelines] to use to reduce suffering and save lives," he said.
WHO added that although air quality has been gradually improving in high-income countries, most places do still exceed current air quality standards. More than 90 per cent of the global population in 2019 lived in areas where concentrations exceeded the 2005 guidelines for exposure to PM2.5.
WHO calculates that countries that meet the new targets could reduce air pollution related deaths by around 80 per cent and the biggest impact would be seen in low and middle income countries.
WHO highlighted how during the pandemic there was an important – although short-term – reduction in air pollution across cities, particularly in the case of nitrogen oxide, which is related to traffic.
The report stated: "Covid-19 has been a tragedy but, at the same time, the response measures have show how policies related to transport and the way people work, study and consume can contribute to a better air quality, something that should be taken into consideration for the post-pandemic recovery policies that many countries are already working on."
Dr Hans Kluge, WHO regional director for Europe, said clean air was a "fundamental human right".
"However, despite some improvement in air quality over the past three decades, millions of people continue to die prematurely, often affecting the most vulnerable and marginalised populations," he said.
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