Three out of four countries affected by excessive microparticle pollution

Three-quarters of countries experienced excessive microparticle pollution in 2020, responsible for numerous premature deaths, despite a significant drop in polluting activities due to the Covid-19 pandemic, according to a report published Tuesday March 16.

In total, 84% of countries experienced a drop in air pollution levels from fine PM2.5 particles (less than 2.5 micrometers) according to this report, compiled by the research branch of the Swiss company IQAir and Greenpeace based on data from terrestrial monitoring stations, two thirds of which are operated by public institutions.

But out of 106 countries with available data, only 24 met the World Health Organization (WHO) standards for these particles, the diameter of which corresponds to one-thirtieth of a human hair . This smallness allows them to enter the blood system via the lungs, causing asthma, lung cancer or heart disease. The majority of the seven million premature deaths worldwide attributed by the WHO to air pollution are caused by PM2.5, from sandstorms, forest fires, agriculture, industry and the combustion of fossil fuels.

Asia hardest hit

“Many regions around the world experienced unprecedented, but temporary, improvements in their air quality in 2020, as Covid restrictions led to a sharp drop in air quality. consumption of fossil fuels”, underlined Lauri Myllyvirta of the Center for Research on Energy and Air (CREA), who also collaborated on the study. For this analyst, quoted in a press release, this reduction made it possible to “avoid tens of thousands of deaths” around the world. Studies have also suggested that exposure to air pollution increases vulnerability to Covid-19 and perhaps promotes the circulation of the virus.

This improvement in air quality in 2020 has already been noted in numerous regional studies, as well as an increase in pollution with the lifting or relaxation of restrictions. As in previous years, South and East Asia were the regions most affected by PM2.5 in 2020: Bangladesh, India and Pakistan account for 42 of the 50 most polluted cities in the world, 49 out of 50 if we add China, where 86% of the cities measured recorded an overall improvement. Among the capitals, New Delhi was the most polluted (as in 2019), with more than eight times the maximum dose recommended by the WHO. Dhaka, Ulaanbaatar, Kabul and Doha follow. Islamabad is 11th, Beijing 15th. At the other end of the table, Stockholm, Helsinki and Wellington are the least affected capitals.

A rare exception to the global decline, the United States recorded an average increase of 6.7% in PM2.5 pollution, attributed to the mega fires which ravaged the north in particular. west of the country. To the point that 38% of American cities studied did not comply with WHO standards in 2020, compared to 21% in 2019.