The place is no longer safe. According to the first global study on air pollution, only 0.18 percent of the earth’s surface and 0.001 percent of the world’s population live in pollution levels that are considered safe by the World Health Organization.
The study – the first to measure PM2.5 particulate pollution in the world – indicates that, in the last 20 years, Europe and North America have reduced their air pollution levels while Asia, Australia, New Zealand, Latin America and the Caribbean have. increased
For decades, the lack of air pollution control stations has made it possible to identify information on local, national and global exposure to PM2.5 (the microparticles most harmful for environmental health).
Now, for the first time, a team of scientists led by Yuming Guo, from Monash University in Melbourne (Australia), has published a map of the evolution of PM2.5 over the last two decades. The results were published Tuesday in The Lancet, Planetary Health.
In conducting the study, the air quality team used traditional monitoring observations, satellite weather and air pollution detectors, and statistical and machine learning methods to more accurately estimate global concentrations of PM2.5.
The paper concludes that annual PM2.5 concentrations and days of high PM2.5 exposure have been decreasing in Europe and North America over the two decades of study, while exposures have increased in South Asia, Australia and New Zealand, and Latin America and the Caribbean. .
The research details that, despite a slight decrease in daily high exposure to PM2.5 worldwide, in 2019 more than 70 percent of days continued to have PM2.5 concentrations above 15 μg/m³.
In Southeast and East Asia alone, more than 90 percent of days had daily PM2.5 concentrations greater than 15 μg/m³.
Additionally, Australia and New Zealand recorded an increase in the number of days with high PM2.5 concentrations in 2019.
Globally, the annual average PM2.5 from 2000 to 2019 was 32.8 µg/m3, according to the study.
The highest PM2.5 concentrations were recorded in Asia (50.0 µg/m3) and South Asia (37.2 µg/m3), followed by North Africa (30.1 µg/m3), and last in Australia and New Zealand (8.5 µg/m³ ), other regions of Oceania (12.6 μg/m³) and South America (15.6 μg/m³).
These data, against WHO 2021 guidelines, show that only 0.18 per cent of the global land area and 0.001 per cent of the global population are below this limit (annual average of 5 μg/m³) in 2013.
The study also shows different seasonal patterns, such as lower pollution levels in northern China and northern India during the winter months (December, January, February), and higher levels of PM2.5 in northeastern areas of the United States during the summer months of June, July and August).
“We also have relatively high PM2.5 air pollution in August and September in South America and from June to September in sub-Saharan Africa,” adds Guo.
For Guo, this information is important to know because “they provide a very deep understanding of the current state of air pollution and its impact on human health.”
“With this information, policy makers, officials and public health researchers can better assess the short and long-term effects of air pollution on health and develop strategies to mitigate it,” defends the researcher.