Main Tehran Air Pollution Culprit: 100,000 Dilapidated Passenger Cars

There are over 100,000 dilapidated passenger cars in Tehran, spewing poison into air and endangering the citizens’ health, the head of Tehran Air Quality Control Company said.
Hossein Shahidzadeh added that over 3.43 million passenger cars ply the capital’s streets every day, 100,000 of which are over 18 years old and have outlived their usefulness, Mehr News Agency reported.   
He added that these old cars emit 579,000 tons of toxins into the air annually, which means 1,586 tons a day.
Giving more specific information, Shahidzadeh noted that of all the pollutants spewed into Tehran’s air annually, these dilapidated cars are responsible for 82% of sulfur oxide, 23% of PM2.5 and PM 10 (atmospheric particulate matters that have a diameter of less than 2.5 and 10 micrometers respectively), 46% of carbon monoxide and 45% of nitrogen monoxide.
He also said PM2.5 is the most harmful pollutant due to its ability to penetrate deep into the lungs and bloodstreams unfiltered, causing heart attacks, respiratory disease and premature death.