Air pollution in Istanbul increased by approximately 9% in February 2026 compared to the same month in 2025, according to a study conducted by Istanbul Technical University (ITÜ). The research, led by Professor Hüseyin Toros of the Department of Climate Science and Meteorological Engineering, examined nitrogen dioxide (NO2) levels across the city and highlighted the significant role of weather conditions in driving pollution.
The study analyzed data from air quality monitoring stations operated by the Ministry of Environment, Urbanization and Climate Change and the Istanbul Metropolitan Municipality (IBB). The average NO2 concentration across 17 stations in February 2026 was 44.1 micrograms per cubic meter, compared to 40.4 micrograms in February 2025, representing a 9% year-over-year increase.
Beşiktaş recorded the highest NO2 levels at 73.5 micrograms per cubic meter, followed by Aksaray at 62 micrograms and Yenibosna at 56.6 micrograms. The lowest concentration was observed in Beylikdüzü at 16.1 micrograms, while Arnavutköy and Avcılar recorded 26.6 and 29 micrograms, respectively.
Of the measured stations, ten saw an increase in nitrogen dioxide, while seven reported a decrease. The largest reductions were in Aksaray, with a 16% decline, followed by Sancaktepe, Selimiye, and Bağcılar, which saw decreases of 8% each. Conversely, the sharpest rises occurred in Çatladıkapı at 94% and Sarıyer at 77%.
Commenting on the findings, Toros said that although internal combustion vehicles and industrial facilities are major contributors to urban air pollution, no significant changes in traffic, heating, or industrial activity occurred in February.
He explained that the increase in pollution was largely driven by meteorological conditions, high-pressure systems can trap pollutants over the city, while low-pressure systems, wind, and rainfall help disperse pollutants and clean the air.
Toros also emphasized the public health impacts of air pollution. Referencing World Health Organization data, he noted that over 90% of the global population breathes polluted air, which adversely affects the respiratory system, cardiovascular health, and brain function. An average person inhales 10-15 kilograms of air daily, making polluted air a serious health concern that also contributes to economic losses and reduced workforce productivity.
To mitigate pollution, Toros advised following traffic rules and driving more calmly, as frequent stop-and-go traffic is a major contributor to emissions. He stressed that slower acceleration and braking reduce fuel consumption and lower pollution. Additionally, he highlighted the importance of industrial facilities adopting more efficient practices and minimizing emissions from fossil fuel use.
The study provides a detailed view of urban air pollution trends in Istanbul, demonstrating the combined influence of human activity and environmental conditions on air quality. It offers a data-driven foundation for public awareness and policymaking to reduce pollution and protect public health in the city.