Not a single country has managed to meet the World Health Organisation’s (WHO) PM2.5 annual air quality guidelines, researchers have said.
Fine particle pollution, known as PM2.5, is commonly accepted to be the most harmful, widely-monitored air pollutant and has been found to be a major contributing factor to health effects such as asthma, stroke, heart and lung diseases. It leads to millions of premature deaths every year.
Last year, MPs urged the UK government to amend the Environment Bill to include targets for lower concentrations of PM2.5.
In an analysis of the WHO data, IQAir found that only the territories of New Caledonia, US Virgin Islands and Puerto Rico met the WHO’s updated guidelines, alongside 222 out of 6,475 global cities covered in the report.
Furthermore, 93 cities in the report had annual PM2.5 concentrations exceeding 10 times the guidelines.
The report covered 2,408 cities in the United States and found that average PM2.5 concentrations actually rose from 9.6 µg/m3 to 10.3 µg/m3 in 2021 compared to 2020. This may have been partially caused by soaring road congestion last year as Covid restrictions were eased across the world.
Of the major cities in the United States, Los Angeles was the most polluted, although it did see an overall decrease in PM2.5 pollution of 6 per cent compared to 2020.
IQAir identified Bangladesh, Chad, Pakistan, Tajikistan and India as the top five most-polluted countries in 2021.
Air quality in China continued to improve in 2021. More than half of the cities in China included in the report saw lower levels of air pollution when compared to the previous year.
China has faced significant public health impacts from its high pollution levels over the years. One report estimated that around 49,000 people in the cities of Beijing and Shanghai had died due to air pollution in the first half of 2020 alone.
The IQAir report found that Beijing had continued its five-year trend of improved air quality, driven by emission control and reduction of coal power plant activity and other high emission industries.
Central and South Asia had some of the world’s worst air quality in 2021 and was home to 46 of the world’s 50 most polluted cities.
Air quality monitoring remains sparse in Africa, South America and the Middle East, although progress has been made by low-cost air quality sensors often operated by non-profit organisations and citizen scientists.
“It is a shocking fact that no major city or country is providing safe and healthy air to their citizens according to the latest World Health Organisation air quality guidelines,” said Frank Hammes, CEO of IQAir.
“This report underscores just how much work remains to be done to ensure that everyone has safe, clean and healthy air to breathe. The time for action is now.”