However, the situation seems to have improved slightly, as last year Brixton Road reached its annual limit in just five days and in 2016 Putney High Street reached the limit in eight days.

 

European Union rules state that air quality monitoring stations must not exceed 200 micrograms of nitrogen dioxide per cubic metre of air during the course of an hour more than 18 times in a year.

 

London Assembly Green Party member Caroline Russell described the exposure of residents in Brixton to illegal levels of air pollution as “a public health catastrophe” which requires “an urgent response”.

 

She added: “The Mayor’s clean bus corridor, where he moved out the dirtiest buses from this route, has given people in Brixton an extra three weeks of clearer air, but it’s still January and they’re already breathing dangerously dirty air.”

 

Caroline Russell added that the Mayor “has a lot of work to do” to restore London’s air quality to legal and safe limits.

 

Friends of the Earth clean air campaigner Oliver Hayes said: “Tougher action is needed to protect more Londoners, sooner. The Mayor should beef up the planned Ultra Low Emissions Zone to include all vehicles in an enlarged zone so it protects people throughout the capital, not just inner London.

 

“But central Government action is also critical,” he added. “A decent scrappage scheme to compensate diesel drivers must go hand in hand with a network of genuinely effective Clean Air Zones across the country.”

 

News of Brixton’s air quality problem came on the same day as London’s Mayor announced that he is to make it easier for schools and community groups to get hold of air quality monitoring sensors.

 

Sadiq Khan has also appointed King’s College London to continuously monitor air pollution in the capital and notify a wider group of stakeholders than is currently the case, so that the alerts are disseminated more widely and targeted at Londoners who are most vulnerable to the impacts of poor air.

 

“At long last we are seeing some improvements in our toxic air, but there is a long way to go before we can breathe easy,” the Mayor said. “I want more Londoners to engage with air quality issues. But I can’t tackle London’s killer air on my own – and it is vital that the Government steps up to the plate and matches my ambition.”