The mayor of London triggered the high air pollution alert on Wednesday (September 27) due to an “air quality crisis” in the capital.

The “shocking and illegal state” of London's air, which Sadiq Khan has declared a public health risk, has led to the alert being triggered for the seventh time in 13 months.

Responding to issuing an urgent "high" pollution alert, the mayor of London urged people to use bikes, public transport or walk instead of using a car.

“The shocking and illegal state of London’s filthy air means once again I am triggering a ‘high’ air pollution alert today under my new comprehensive alert system,” he said.

“Safeguarding the health of Londoners from toxic air is an important priority for me as Mayor.

“I am implementing the boldest policies of any city in the world, which includes introducing the T-charge next month to tackle emissions from the oldest polluting vehicles and bringing forward the Ultra Low Emission Zone with even tighter standards in April 2019.

London is facing an "air quality crisis"

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“I have doubled funding to improve London’s air quality to £875 million and I am cleaning up the capital’s bus and taxi fleets.

“I am doing everything with the powers I have at City Hall and it’s now time for the government to step up by introducing a national diesel scrappage fund to rid our streets of dirty diesels, and to give me the powers I need to tackle non-transport sources of pollution.”

According to the mayor of London, this latest episode was caused by toxic emissions blown over from Europe, coupled with London's “filthy air”.

This, he suggests, means Britain must work closely with the European Union post-Brexit to effectively address the “air quality crisis our city faces”.

Sadiq Khan has triggered the 'high' pollution alert

He added on Twitter: “If you have any pre-existing medical conditions or breathing difficulties, such as asthma, please carry medication with you.

“Walk, cycle or use public transport if you're able to, to help us cut emissions and pollution.”

The government's advice during "high" pollution suggests adults and children with lung problems, and adults with heart problems, should reduce strenuous physical exertion, particularly outdoors, and particularly if they experience symptoms.

People with asthma may find they need to use their reliever inhaler more often and older people should also reduce physical exertion.

Anyone experiencing discomfort such as sore eyes, cough or a sore throat should consider reducing activity, particularly outdoors.

The last recorded high pollution in London was on June 21 this year.

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