Less than 1% of the land area is regarded as safe for the concentration of fine particulate pollutants. This finding is highlighted in a report informed by sources from The Lancet Planetary Health.
Researchers have tracked atmospheric pollution driven by PM2.5 particles, which are as small as 2.5 microns. Medical professionals have long linked elevated levels of these particles in inhaled air to cardiovascular disease, and there are inquiries into their ability to penetrate multiple organs with outcomes that remain under study. The data set spans meteorological records from 2000 to 2020 and surveys conducted by environmental monitoring stations across 65 countries.
The analysis indicates that the majority of people live in zones where PM2.5 concentrations exceed the doctor-recommended threshold of 5 µg per cubic meter.
In 2019, only 0.18% of land and 0.001% of the global population experienced average annual PM2.5 exposure below 5 μg/m3, according to the study. The researchers point to the highest pollution levels in East Asia, South Asia, and parts of North Africa. In contrast, regions such as Australia, New Zealand, other parts of Oceania, and much of South America recorded lower average annual PM2.5 levels, even as the number of days above the norm climbed in some areas. Daily PM2.5 concentrations exceeded 15 μg/m3 for more than 90% of days in 2000, 2010, and 2019 in parts of South and East Asia.
The authors hope the findings prompt authorities to acknowledge the threat posed by microscopic particulates and to consider establishing separate environmental standards to curb exposure.
Public health advocates have long called for practical solutions—such as improved urban planning, stricter industrial controls, and greener transportation—to minimize airborne PM2.5 and protect vulnerable communities. The evidence underscores the need for clear, actionable policies that translate scientific insight into healthier air. The conversation now shifts toward accountability, monitoring, and measurable targets that cities across Canada and the United States can adopt to reduce exposure and improve air quality for residents.
What are the best trees to purify the air in the city? This question often arises in conversations about urban air quality, and while vegetation can help, it should be viewed as part of a broader strategy that includes emissions reductions, enhanced filtration in buildings, and community engagement to monitor air conditions. The overall message is simple: better air starts with stronger standards, consistent monitoring, and collaborative action among governments, industry, and citizens.