Sarajevo, choked by toxic air: Bosnia's capital, once again tops the world's pollution rankings

Sarajevo, the capital of Bosnia and Herzegovina, was once again at the top of the world's most polluted cities last week, after levels of fine particles in the air reached values considered extremely dangerous to health. The situation prompted local authorities to declare a state of alert, according to data provided by the Swiss company IQAir, which monitors air quality globally, information taken over by AFP.

• A city caught under the lid of a thermal inversion

Severe episodes of pollution are nothing new for Sarajevo, a city of around 400,000 inhabitants, located in a valley and surrounded by mountains. Especially in winter, the phenomenon of thermal inversion becomes a key factor: a layer of warm air sits above cold air, blocking the dispersion of pollutants and transforming the city into a real closed container. In these conditions, emissions from individual heating with wood and coal, combined with intense road traffic, remain trapped above the city, leading to rapid accumulations of harmful particles.

• "Dangerous” levels and seasonal records

According to IQAir, the concentration of PM2.5 particles - microparticles small enough to enter the bloodstream and associated with an increased risk of cancer and cardiovascular disease - reached 299.3 micrograms per cubic meter (µg/m³). The value exceeds almost 20 times the daily limit recommended by the World Health Organization (WHO). Last Thursday, the air quality index even climbed to 462 micrograms per cubic meter, placing it in the "hazardous” category, one of the worst classifications used internationally. "Daily concentrations of fine particles were the highest on Thursday since the beginning of winter and there is a risk that they will remain at a similar level on Friday,” Enis Krecinic, an environmental expert at the Meteorological Institute in Sarajevo, told AFP.

• "Extremely polluted”: the worst possible scenario

According to the expert, the situation is also critical in national assessments. "And in our ranking, which includes six categories of air quality, the index is at the worst possible level, category 6, that of extremely polluted air,” Krecinic explained. At most monitoring stations in the Bosnian capital, average daily concentrations of PM10 - particles with a diameter of up to 10 micrometers - exceeded 200 micrograms per cubic meter, reaching as high as 230 to 270 micrograms per cubic meter. The threshold considered acceptable is 50 micrograms per cubic meter, which means that current values are four to five times higher than the tolerated limit.

• A chronic problem, with lethal effects

The seriousness of the situation is also confirmed by European data. According to a study published in December 2025 by the European Environment Agency (EEA), Bosnia and Herzegovina is among the countries most affected by air pollution in Europe. In 2023, 199 premature deaths per 100,000 inhabitants were attributed to exposure to fine particles. These figures place Bosnia in the negative top of the continent, highlighting the structural nature of the problem: outdated energy infrastructure, high dependence on solid fuels and insufficient measures to reduce urban emissions.