Our cities are polluted?

The pollution is mainly in large cities or industrial sites, but it varies in time and space. Since the 70s, there was a significant improvement in air quality and pollution are some way of 'be controlled. These include pollution by sulfur in most French cities. But today, most of us are exposed to pollution from cars and road transport. The proximity of many industrial sites is affected by discharges from factories. In space, air quality varies even within the city. It is rather good in protected areas and places where traffic is low. It becomes bad when you are in an area of significant traffic.
Other factors can affect the air quality. Examples of weather. How about the air quality? By the ATMO index ranging from 1 (excellent) to 10 (horrible), which gives an average over the city. It is calculated from the measured concentrations of major pollutants like sulfur oxides, nitrogen oxides, ozone and particulates. Moreover, the development of networks for measuring air quality, will in future to better understand the state of pollution and its distribution.