Wire: Global air quality is deteriorating, posing a risk to public health, in what has become just the latest of a series of warnings from the World Health Organization on the state of the world's skies.
Air quality in most cities fails to meet the organization's health guidelines, according to the new report, and it looks set to increase the risk of developing or worsening respiratory illnesses and other health problems. The WHO's Urban Air Quality database covers 1,600 cities in over 91 countries...