Tehran Saw Unprecedented Polluted Days in Norouz

During the 13 days of the new Iranian year, which started on March 21 and coincides with the Norouz holidays, Tehran experienced five days of unhealthy air quality, an exceptional record in 10 years. 
Tehran is known for its less crowded streets and clean air during the springtime holiday season when many take trips outside the city. This year's figures, however, caused surprise. 
Vahid Hosseini, director of Tehran's Air Quality Control Company—a subsidiary of Tehran Municipality, attributed the condition to dust particles blowing from domestic sources, along with the exceptional traffic across the city.