How to win the war on air pollution | Letters

Damian Carrington is half right (The war against air pollution has begun - and it will be fought in cities, 13 February) in that cities bear a terrible burden from air pollution and municipal action is critical to address it. However, city governments cannot succeed alone. Much of urban pollution stems from outside city limits and significant progress will only be achieved with policies that also require national, regional and even international commitment.

A significant part of city air pollution drifts in from regional sources like wood-burning rural households, coal-fired power plants, industries and the open burning of agricultural waste and rubbish. Commuters driving in from car-centric suburbs and transport between cities contribute to urban congestion and pollution too, stymying smart city initiatives like investments in public transportation and safer streets for walking and cycling.