Teheran heavily polluted

In Tehran, 80% of the pollution is due to exhaust fumes. The fleet is valued at 5 million vehicles and 3.5 million two-wheelers. Although the number of highly polluted days per year has dropped from 98 to 48 days over the last 5 years, this figure is rising again in 2017 to 58 highly polluted days. Due to the altitude at which it is located, the agglomeration is subject to the phenomenon of thermal inversion. The pollution clouds stagnate in the region. The absence of rain at the end of the year did not help to improve the situation.