In December, a commuter rode a bicycle through the polluted air of Noida, India. A new report reveals that six of the world’s ten most polluted cities are located in India, with California having the worst air pollution in North America. The 2024 World Air Quality Report, published by IQAir, indicates that New Delhi is the most polluted capital city globally, followed by N’Djamena in Chad, a country with the world’s severest air pollution. The report also highlights that ten out of the 15 most polluted cities in North America, including Ontario and Bloomington, are found in California, making the United States the most polluted country in the region for 2024.
Despite a 7% reduction in PM2.5 concentration in India in 2024, air pollution remains a significant health concern, reducing life expectancy by an estimated 5.2 years. Major sources of pollution in the country include industrial emissions, construction dust, and the burning of crop residues. PM2.5, tiny particles that can penetrate deep into the lungs and bloodstream, mainly originate from sources like gasoline and oil combustion, leading to health issues such as premature death, heart problems, and respiratory difficulties.
While the World Health Organization recommends that average annual PM2.5 concentrations should not exceed 5 micrograms per cubic meter, only 17% of global cities meet this standard. In contrast, Chad’s PM2.5 levels were over 18 times higher than the WHO guideline, primarily due to mineral dust from the Sahara Desert. Oceania stands out as the cleanest region globally, with 57% of its cities meeting the WHO air quality standard.
Neighboring countries Bangladesh and Pakistan rank as the second and third most polluted countries, respectively. Last November, Pakistan experienced hazardous air quality levels due to factors like festival celebrations, emissions from brick kilns, and adverse weather conditions. China, the largest emitter of greenhouse gases, saw reduced air pollution levels in more than 300 cities in 2024. Despite setting ambitious goals to lower annual average PM2.5 concentrations, China still exceeds the WHO guideline by a significant margin.
The report also highlights the disparities in air quality monitoring worldwide, with only 21% of the global population having access to hyper-local, real-time air quality information. While North America boasts a robust monitoring infrastructure, regions like Cambodia, Africa, and West Asia lack sufficient monitoring capabilities. Overall, air pollution remains a critical threat to human health and the environment worldwide.
“Many people are unaware of their exposure levels despite the importance of mental stability,” stated Frank Hammes, the global chief executive of IQAir. He emphasized the significance of air quality data in saving lives, raising awareness, shaping policies, guiding public health interventions, and empowering communities to combat air pollution and safeguard future generations. Recently, U.S. embassies and consulates ceased air quality monitoring abroad, discontinuing a program that had supplied crucial public health information for over a decade. Studies revealed that the data provided by the U.S. had led to tangible enhancements in local air quality in countries like China, resulting in reduced premature deaths and cost savings linked to lower mortality rates. According to the WHO, air pollution caused 8.1 million deaths worldwide in 2021, with children under 5 being particularly vulnerable to health issues such as premature birth, low birthweight, asthma, and lung disease.
