But recent research has shown how air pollution even in comparatively clean cities in the United States and Europe continues to cause health problems — largely due to the prevalence of diesel vehicles — despite government initiatives to address it. (health.com)
«Efforts should be made to limit air pollution emissions, with more emphasis on moving towards cleaner cities with fewer cars and more efficient public transport.» (ersnet.org)
: Ad ban in SÃ # o Paulo by Veja «A few months ago, the fourth largest metropolis SÃ # o Paulo put into effect a radical ban on outdoor advertising called «Lei Limpia Cidade» or «Clean City Law». (treehugger.com)