Scientists at the Health Impact Institute in the US have published a new report on global air pollution, reports The Guardian. In their analysis, they used satellite and ground-based measurements of airborne particulate matter (PM2.5) and nitric oxide (NO2).
Moscow and St. Petersburg were in the top four most polluted with nitric oxide among more than 7,000 cities in the world. In the first place - Shanghai, in the third - Tehran. Several more cities from the post-Soviet space made it into the top ten: the capital of Turkmenistan, Ashgabat, and the capital of Belarus, Minsk, took seventh and eighth places. The study included NO2 data for the period from 2010 to 2019.
Study leader Pallavi Pant commented: “Finding several Russian cities at the top of the list [for NO2 air pollution] was quite unexpected for us. This is probably mainly due to traffic pollution and an outdated fleet.”
Vehicles are considered a major source of nitric oxide pollution, with older cars producing much more of it than modern models. NO2 is not as strongly associated with mortality as particulate pollution, but it can cause respiratory problems such as asthma in children.
If cities in relatively prosperous countries are at the top of the anti-ranking for nitrogen oxide pollution, then poorer countries suffer from PM2.5 pollution. The source of particulate matter in the air is usually coal-fired power plants, the burning of waste and agricultural products, and vehicles. The most unfavorable situation with PM2.5 is in Asia, Africa and Eastern and Central Europe. In the first places are Delhi and Calcutta (India), Kano (Nigeria), Lima (Peru).