Philip Barlow, coroner for inner south London, said Ella Kissi-Debrah died in February 2013 as a result of acute respiratory failure, severe asthma and air pollution exposure.

The girl was exposed to nitrogen dioxide as well as particulate matter (PM) pollution at levels above World Health Organization guidelines.

The main source of the pollution was traffic emissions.

“Ella died of asthma contributed to by exposure to excessive air pollution,” the coroner said yesterday.

“The whole of Ella’s life was lived in close proximity to highly polluting roads. I have no difficulty in concluding that her personal exposure to nitrogen dioxide and PM was very high.”

He added that the effects of pollution had been known for many years and that children with asthma were particularly vulnerable.

The coroner said the health effects of air pollution had been known for many years, and children and those with asthma were particularly at risk.

A government spokesperson said: “Our thoughts remain with Ella’s family and friends. We are delivering a £3.8bn plan to clean up transport and tackle NO2 pollution, and going further in protecting communities from air pollution, particularly PM2.5 pollution, which we know is particularly harmful to people’s health.

“Through our landmark environment bill, we are also setting ambitious new air-quality targets, with a primary focus on reducing public health impacts.”