Tehran experienced its cleanest air on November 29 with an Air Quality Index (AQI) of 63, while December 19 marked the most polluted day with an AQI of 174.
Particulate matter smaller than 2.5 microns was the primary pollutant on all polluted days, with one day also recording particulate matter smaller than 10 microns in the undesirable range.
Research shows that exposure to these fine particles, which are often byproducts of combustion and industrial processes, leads to several health complications.
These include premature death in heart and lung disease patients, nonfatal heart attacks, irregular heartbeat, lung cancer, worsened asthma, reduced lung function, and increased respiratory symptoms.
Tehran’s air quality on Saturday morning stood at an AQI of 91, indicating acceptable conditions after four continuous days of unhealthy air.
