To compile our ranking, we rely on Yale University’s Environmental Performance Index (EPI) (2024 report). The EPI evaluates key pollutants such as PM2.5, ozone, carbon monoxide, sulfur dioxide, volatile organic compounds, and more, providing a comprehensive view of a nation’s environmental health.
We also draw on the Air Quality Life Index (AQLI) from the University of Chicago (2022 data), which offers the latest PM2.5 figures—critical for assessing fine particulate matter that affects human health worldwide.
EPI rating: 6.1
PM2.5: 39.18 µg/m³
Nepal holds the unfortunate distinction of having the world’s highest air pollution levels. Both outdoor and household pollution are pervasive, driven by limited development, weak regulatory frameworks, and inadequate infrastructure.
Fine particulate matter accumulates in Nepal’s mountainous terrain, acting as a natural “pollution sink” that traps industrial and urban emissions from neighboring China and India. Additional contributors include aging vehicle fleets, widespread trash burning, and residual dust from the 2015 earthquake.
EPI rating: 6.3
PM2.5: 38.9 µg/m³
Pakistan ranks second, grappling with air quality challenges amid rapid urbanization and a mixed industrial-agricultural economy. Emissions stem from vehicle traffic, factories, seasonal crop burning, and the country’s geographical and climatic conditions.
EPI rating: 6.3
PM2.5: 54.17 µg/m³
Bangladesh, densely populated and rapidly industrializing, mirrors issues seen in India and China. The explosive growth of brick factories—both large and small—fuels pollution through coal and biomass combustion.
EPI rating: 6.8
PM2.5: 41.39 µg/m³
India’s air quality remains emblematic of the environmental cost of economic growth. Key sources include vehicular emissions (particularly from older models), industrial processes, stubble burning for agriculture, and domestic fuel combustion.
Despite increasing regulatory efforts, progress remains incremental, underscoring the complexity of the problem.
EPI rating: 8.1
PM2.5: 34.20 µg/m³
Despite its mineral wealth, the DRC suffers from severe indoor and ambient pollution. Wood stoves are ubiquitous, and urban areas experience high emissions from unregulated industrial activity and motor traffic.
Ongoing conflict hampers sustainable development and regulatory enforcement, perpetuating a public health crisis.
EPI rating: 8.4
PM2.5: 33.37 µg/m³
Rwanda’s air quality issues mirror those of its neighbor, the DRC. Indoor pollution from wood and charcoal cooking poses significant health risks, especially to vulnerable populations such as children, the elderly, and pregnant women.
EPI rating: 9.0
PM2.5: 28.64 µg/m³
Myanmar faces familiar pollution challenges as it undergoes urbanization and industrialization. Regional influences from neighboring countries exacerbate the problem, especially when prevailing winds transport pollutants.
EPI rating: 9.0
PM2.5: 34.04 µg/m³
Burundi contends with similar air quality pressures as Rwanda and the DRC. Indoor cooking on wood stoves dominates, while urban areas lack stringent pollution controls.
EPI Rating: 11.6
PM2.5: 27.87 µg/m³
Enclosed within South Africa, Lesotho’s air quality is affected by trash burning and emerging industrial activities. Developmental growth often sidelines environmental safeguards.
EPI Rating: 12.1
PM2.5: 31.94 µg/m³
While smaller than its namesake, the Republic of Congo also grapples with significant air pollution, posing substantial health risks to its population.
Across all ten countries, PM2.5 levels far exceed the World Health Organization’s safe limit of 10 µg/m³, highlighting urgent needs for comprehensive policy action and public health interventions.
