In light of the astonishing results achieved in lowering air pollution by the introduction of the ultra-low emission zone (Ulez) in London by Sadiq Khan (Ulez led to better lung size and function among London children, study finds, 18 August), should we now not extend this philosophy into every city in the UK to save lives?

Surely it is a human right to breathe clean air? Why does Ofsted or the Department for Education not insist on air-quality monitors and give data for each school so parents are aware of the risks?
Lorna Henderson
Newcastle upon Tyne

Thank you, Sadiq Khan, for showing what can be achieved when politicians ignore the loudest voices and stand up for what they believe and act in the interests of the whole population (Introducing Ulez was my hardest decision as mayor of London – but now we know its astonishing impact, 18 August). At a time when the government’s ability to do the right thing to protect the people of this country against the multiple threats posed by climate change, he has demonstrated that it is possible to truly lead in the face of self-interest and populism.
George Coleby
Worthing, West Sussex

In the last decade, the fight for cleaner cities has become yet another culture war, and the ones suffering are the people living there every day. Sadiq Khan’s Ulez is an incredible way of addressing multiple issues such as traffic congestion, emissions and noise pollution, as well as creating space for pedestrians and cyclists.

We can only hope this is taken further still and we’ll see more bicycle-friendly streets, more low-traffic neighbourhoods, more trees and improved public transport. We only have to look across the Channel and notice how Paris has transformed itself with similar measures. Let’s make it a friendly competition of who can make their capital a healthier, more livable city.
Leonard Neamtu
Bucharest, Romania