According to the World Health Organization (WHO), Chad and Bangladesh topped the list of the world’s most polluted countries in 2024. Their average pollution levels were more than 15 times higher than WHO’s air quality guidelines. IQAir, a global air quality monitoring agency, reported that only seven countries met WHO’s air quality standards: Australia, New Zealand, the Bahamas, Barbados, Grenada, Estonia, and Iceland. The battle against pollution is expected to become more challenging, especially after the U.S. discontinued its global air quality monitoring initiative.