Tube's high dust levels

Tube passengers are breathing in dust levels up to 14 times higher than the recommended safety level, an Evening Standard investigation reveals today.

The findings emerge from a survey of some of the capital's busiest Tube stations just days after London Underground admitted its only vacuum train for removing dust has broken down.

A leading scientist today warned dust levels were so high that warning signs should be displayed at stations to inform people of the risks. Professor Nick Priest, head of the Urban Pollution Research Centre at Middlesex University, said: "These levels could potentially cause premature death. I see no reason why people, particularly those in at-risk groups like asthma sufferers, should not be given a precautionary warning." Using an air-quality measuring device of the same kind employed by environmental scientists, the Evening Standard found levels of dust in the Tube which far exceed the Government's recommended safe outdoor level of no more than 50 micrograms of dust per cubic metre for each person.

Readings were taken on the Northern line, one of the busiest and deepest on the network. Recorded at stations in the evening rush-hour, the readings revealed dust levels up to 14 times above the safety limit.

They included 726 micrograms of dust per cubic metre on the southbound platform at Goodge Street and 635 micrograms per cubic metre on the southbound platform at Euston.

The dust includes particles of iron and silicon which have been linked to heart and liver problems and lung disease.

Professor Priest said: "If this level of dust is regarded as a health risk which should be regulated above ground, it should be regulated below ground as well."

Dr Barry Gray, consultant in respiratory medicine at King's College Hospital, also believes the dust particles carried significant health risks.

He said: "Exposure to fine particles has been linked to early death for those with chronic heart disease, an increased risk of attacks for asthmatics and inflamed airways even for those who aren't sufferers."

In 2001 scientists from University College warned that a 20-minute journey through central London on the Northern line had the same effect as smoking a cigarette.

A spokeswoman for London Underground said: "We are working with our business partners to ensure proper cleaning standards are maintained."