The World Health Organisation (WHO) has recently released their 2022 Air Quality Database, bringing attention to the global issue of polluted air. Shockingly, it reports that almost 99% of the world’s population breathes air exceeding WHO’s air quality limits. The report was released ahead of World Health Day on April 7th.
Comprehensive Ground Measurements
For the first time, WHO has taken ground measurements of annual mean concentrations of nitrogen dioxide (NO2), a harmful air pollutant. The study also includes measurements of Particulate Matter with diameters equal or smaller than 10 μm (PM10) or 2.5 μm (PM2.5). These harmful particulates can penetrate deep into our respiratory system, causing significant health issues.
A Call-to-action for Air Pollution Reduction
The alarming findings have spurred WHO to emphasize the urgency of reducing fossil fuel use and implementing practical measures to lower air pollution levels. Contextualizing this urgent call is the 2021 World Air Quality Report by the Swiss group IQAir, which noted that India had 11 out of the 15 most polluted cities in Central and South Asia that year.
The Stark Findings: Unhealthy Air and Increased Data Collection
Despite increased efforts to monitor air quality in over 6,000 cities across 117 countries, residents continue to breathe unhealthy levels of fine particulate matter and nitrogen dioxide. People in low to middle-income countries suffer the worst exposure. Notably, data collection has increased, with about 2,000 more cities actively monitoring particulate matter compared to the last update in 2018.
Damaging Impact of Air Pollution
Broader evidence continues to show that even low levels of major air pollutants can cause significant harm to human health. Particulate matter, notably PM 2.5, can penetrate deep into the lungs and bloodstream, leading to cardiovascular, cerebrovascular (stroke), and respiratory impacts. NO2 is linked with respiratory diseases such as asthma, leading to symptoms like coughing, wheezing, or difficulty breathing and increased hospital admissions.
Compliance with WHO Air Quality Guidelines
Reviewing the 117 countries monitoring air quality, only 17% of cities in high-income countries have air that falls below WHO’s air quality guidelines for PM 2.5 or PM 10. In low and middle-income countries, less than 1% of the cities comply with WHO’s recommended thresholds.
New Air Quality Guidelines by WHO
To tackle this environmental crisis, WHO’s 2021 guidelines recommend new air quality levels to mitigate key air pollutants, some of which also contribute to climate change. The guidelines recommend air quality limits for six pollutants known to have detrimental health effects: PM 2.5 and 10, ozone (O3), nitrogen dioxide (NO2), sulfur dioxide (SO2), and carbon monoxide (CO).
Strategies for Improved Air Quality and Health
WHO suggests several measures to improve air quality. These include revising and implementing national air quality standards, monitoring air quality, transitioning to clean energy sources for household use, building efficient public transport systems, implementing stricter vehicle emissions and efficiency standards, investing in energy-efficient housing, improving industry waste management, reducing agricultural waste incineration, and including air pollution education in health professional curricula. Through these comprehensive measures, it’s hoped that we can combat this global threat to public health and our environment.
