SINGAPORE (Reuters) – In 2024, only seven countries worldwide met the World Health Organization's (WHO) air quality standards, highlighting the growing global struggle with air pollution. According to data released on Tuesday by Swiss air quality monitoring firm IQAir, Chad and Bangladesh ranked as the most polluted countries, with smog levels exceeding WHO recommendations by more than 15 times.

The countries that successfully met WHO air quality criteria were Australia, New Zealand, the Bahamas, Barbados, Grenada, Estonia, and Iceland, IQAir reported.

However, significant data gaps remain, especially in parts of Asia and Africa, which complicates the global understanding of air pollution levels. Many developing countries, especially those in Africa, have heavily relied on air quality data provided by sensors mounted on U.S. embassy and consulate buildings. But this crucial source of information has been cut off after the U.S. State Department ended the monitoring program due to budget constraints. Last week, more than 17 years' worth of air quality data was removed from the U.S. government's air quality site, airnow.gov, including vital readings from countries like Chad.

Christi Chester-Schroeder, air quality science manager at IQAir, noted that while some countries still have other sources of data, Africa would be disproportionately impacted by the loss of U.S. embassy sensors, as many regions in the continent rely on these real-time air quality readings for public information.

Chad, which was excluded from IQAir's 2023 rankings due to data gaps, topped the list as the most polluted country in 2022. The country's average levels of PM2.5, tiny airborne particles that can harm human health, reached a staggering 91.8 micrograms per cubic meter (µg/m³) last year. The WHO recommends a maximum of 5 µg/m³ for safe air quality, a standard only achieved by 17% of cities globally in 2024.

India, which ranked fifth in the pollution list, showed some improvement in its air quality, with PM2.5 levels decreasing by 7% from the previous year to 50.6 µg/m³. However, it remained home to 12 of the top 20 most polluted cities worldwide, including Byrnihat, a heavily industrialized area in the northeast, which topped the global chart with a PM2.5 average of 128 µg/m³.

Climate change is also worsening the air quality crisis, with rising temperatures leading to more intense and prolonged wildfires across Southeast Asia and South America. These fires significantly contribute to elevated pollution levels, further exacerbating the smog problem.

Christa Hasenkopf, director of the Clean Air Program at the University of Chicago's Energy Policy Institute (EPIC), warned that at least 34 countries would lose access to reliable air quality data due to the cessation of the U.S. embassy monitoring program. This initiative, she explained, had already been instrumental in improving air quality in the cities where sensors were placed, contributing to increased life expectancy and even reducing health hazard allowances for U.S. diplomats. Its termination, she emphasized, was a major setback for global air quality efforts.

In summary, while some countries continue to meet air quality standards, global pollution levels are worsening, with data gaps and climate change posing additional challenges to fighting air pollution worldwide. The loss of crucial air quality data will only add to the difficulties in addressing this growing crisis.