Pollution from Heathrow planes is reaching central London, study shows [Evening Standard, 03/01/20]

Pollution from planes using Heathrow airport has been detected in central London, researchers revealed today.
A breakthrough study by King’s College London is the first to find that airports are a major source of ultra-fine particles that are harmful to health.
Results from air quality monitoring stations in north Kensington and in Marylebone Road — about 14 miles from the airport — were used to estimate levels of the particles in the air.
These were greatest when blown in from the airport on a westerly wind.
Ultra-fine particles are produced by fuel burning and are a subset of PM2.5 particles that are most commonly emitted from traffic brakes and tyres.
The smaller the particle, the deeper they can penetrate into the lungs. Ultra-fine particles have been linked to brain cancer.
The King’s study, in Environment International, measured emissions from four European airports — the others were Barcelona, Zurich and Helsinki — between 2007-17.