Tube air is safer than inside cars

Travelling on the Tube is healthier than driving on London's roads, doctors said today.

Research has shown that, although it may seem dusty, commuters are actually exposed to less fine-particle pollution on the Underground than they would be on London's roads.

The study, commissioned by London Underground and published today in the journal Occupational and Environmental-Medicine, said the Tube harboured larger and heavier particles.

These spend less time airborne and are less likely to be inhaled deeply, so are less dangerous, though not entirely safe.Harmful mineral levels were also well below those allowed in the workplace.

Researchers from the Institute of Occupational Medicine in Edinburgh tested the air at Holland Park, Hampstead Heath and Oxford Circus stations, as well as inside cars. Despite the positive findings they cautioned Tube bosses to continue efforts to reduce dust because it was "not without toxicity".

In an accompanying editorial Dr Roy Colvile, a pollution expert at Imperial College, said staff and passengers should be reassured by the findings - but bear in mind that no dust is without any risk.

He said: "As long as dust removal remains so poorly understood, staff and passengers will continue to be exposed to this air pollutant."

Past studies have shown that the fine dust levels on London's busy roads can lead to breathing disorders and even cancer.