A section of the London Marathon route saw an 89 per cent drop in air pollution on race day, according to new figures.
The research, published by Global Action Plan, utilised data collected by monitoring stations managed by Kings College London .
Monitoring over a 12-hour period - from 7am to 7pm - experts found the air quality along Upper Thames Street improved by almost nine tenths.
Larissa Lockwood, Head of Health at Global Action Plan said, “Taking collective action to tackle air pollution every day can make a massive difference, as shown at the London Marathon.
“With traffic free streets pollution levels dropped by 89 per cent. Imagine if more people left the car at home every day.
"We would suffer far fewer health problems from air pollution.”
Analysis of the King’s College pollution data on the day of the London Marathon compared to the previous three Sundays in April 2018 found a significant drop in pollution levels across all pollutants.
The group cited the data as it renewed its calls for a "car-free day" in London on June 21.
A leading engineering organisation recently called for more research to be done on he effects of commuters breathing in dust on the London Underground.
The Institution of Mechanical Engineers called for "urgent action" to tackle the capital's "dangerous" levels of air pollution, including blackspots on the Tube network.
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