Tehran and several other industrial cities will face a severe decline in air quality beginning on Monday, according to Iranian meteorological reports.
The head of Air and Weather Predictions, Abdolreza Omidvar, told the Mehr News Agency that on Monday and Tuesday, increased emissions will result in heavy pollution in Tehran, Isfahan, Arak, Karaj and Mashhad.
Each year from the end of fall until the beginning of winter, Tehran and other industrial centres endure severe air pollution.
In recent weeks, heavy pollution has prompted the closure of elementary schools in Tehran. According to some reports, 50 people die every day in Tehran due to air pollution.
The southwestern Iranian city of Ahwaz was recently highlighted by the World Health Organization as the most polluted city on Earth.