The 2025 IQAir World Air Quality Report places Colombia 88th out of 143 countries in global pollution rankings, with a national PM2.5 average of 11.1 micrograms per cubic meter. The report compiles data from 9,446 cities across 143 countries, drawing on more than 40,000 monitoring stations and sensors worldwide.
Colombia’s PM2.5 level is 2.2 times the World Health Organization’s annual guideline value. Still, the country is heading in the right direction. The national PM2.5 average dropped from 13.8 μg/m³ in 2024 to 11.1 μg/m³ in 2025. Researchers confirm that concentrations fell across all highlighted cities, including Bogota, Medellin, Bello, and Envigado.
Colombia makes steady gains on air quality
Bogotá recorded the strongest progress. The capital posted an annual PM2.5 average of 10.0 μg/m³ in 2025. The IQAir report notes this marks the first year Bogotá met the WHO Interim Target 2 guideline, which sets an annual cap at or below 10 μg/m³. The city has cut air pollution by 24% since 2018.
It launched 1,400 electric buses, built Latin America’s largest cycle network, and restricted heavy freight traffic. Bogota also opened its first Urban Zone for Clean Air in Bosa, designed to integrate safer walking and cycling in a high-density, low-income neighborhood. These efforts earned the city the prestigious “Clean Our Air” Earthshot Prize.
Other cities in Colombia posted moderate readings. Medellín recorded 13.4 μg/m³, Envigado came in at 12.8 μg/m³, and Bello registered 14.6 μg/m³ in 2025.
Key factors behind Colombia’s global pollution rankings
Colombia’s pollution comes from several sources. Inside cities, vehicular exhaust, dust from unpaved roads, and industrial emissions are the main contributors. In rural areas, the burning of wood and coal for cooking and heating keeps background pollution levels high.
Beyond local sources, the IQAir report points to longer-range factors. Nevado del Ruiz, an active volcano, pumps around 7 μg/m³ of background PM2.5 into the atmosphere through sulfate aerosol formation. Northeast trade winds also carry particulate matter from biomass burning in Venezuela’s Orinoco River Basin into Colombia, driving sharp seasonal spikes in the Andean region between January and May.
Temperature inversions during February and March push monthly readings higher than the rest of the year. Even so, no city in Colombia exceeded a monthly average of 25 μg/m³ in 2025. That compares favorably to 2024, when several cities crossed 30 μg/m³ during March.
The country’s position in 2025 global pollution rankings reflects real gains, but the gap between current levels and WHO targets means sustained effort remains essential.
Most polluted countries in the world in 2025
1. Pakistan (67.3 μg/m³)
2. Bangladesh (66.1 μg/m³)
3. Tajikistan (57.3 μg/m³)
4. Chad (53.6 μg/m³)
5. Democratic Republic of Congo (50.2 μg/m³)
6. India (48.9 μg/m³)
7. Kuwait (45.7 μg/m³)
8. Uganda (43.0 μg/m³)
9. Egypt (40.6 μg/m³)
10. Uzbekistan (38.1 μg/m³)