Londoners have been warned that high levels of fine particulate matter have been monitored across the capital today (27 September).
The warning has prompted City Hall to issue an air quality alert, which has seen warning messages featured across the cityâ€™s travel network.
According to London Air, the capitalâ€™s air quality monitoring network, which is operated by Kingâ€™s College Londonâ€™s Environmental Research Group, the high air pollution reading has been sparked by a large high pressure system centred over northern Scandinavia, which has resulted in an easterly air feed from the continent.
In a forecast this morning, London Air added: â€œThe air arriving on Wednesday will have again travelled slowly and at low altitudes across industrialised parts of Europe giving it time to pick up emissions on the way.
â€œThis will add to the preceding dayâ€™s pollution and combined with London’s own emissions to likely produce ‘High’ levels of PM2.5 and ‘Moderate’ levels of PM10 particulate pollution across areas of London and the South East.â€
Commenting on the conditions, the Mayor of London, Sadiq Khan, said: â€œThe shocking and illegal state of Londonâ€™s filthy air means once again I am triggering a â€˜highâ€™ air pollution alert today under my new comprehensive alert system. This is the seventh time in 13 months that we have had to use the alert system and shows just why air pollution is a public health crisis.â€