Commuters using public transport are exposed to up to eight times more pollution than car users, research suggests.
Even though motorists produce the most pollution per commuter, they are the least exposed to harmful particulate matter as they are sealed off from the outside, the study by the University of Surrey found.
The team compared how commuters using cars, buses and the underground in different areas of London were exposed to a range of pollutants.
The study, published in the journal Environment International, found that commuters on some underground lines are the most exposed to poor air quality, followed by those on buses.
Monitors worn by commuters found those on the tube were exposed to 68 micrograms of PM10, tiny particles of soot that are breathed into the lungs, compared to eight micrograms of exposure experienced by motorists.