PASSENGERS and staff on the London Underground risk breathing in air pollution 18 times worse than above ground, according to scientists.
They absorb toxic particles known as PM2.5 — which have a diameter of less than 2.5 millionths of a metre — through iron-based dust on brakes, wheels and rails, fragments of clothing and passengers’ dead skin cells, found the University College and King’s College London study.
The Victoria Line was worst with a peak of 885 microgrammes per cubic metre, 22 times higher than World Health Organization limits.
UCL’s Brynmor Saunders told The Sunday Times that if the health impacts are the same as surface-level pollution, ‘a person with this exposure would have a seven per cent to 11 per cent higher chance of death due to increased risks of cardiovascular diseases’.
He went on: ‘Most people don’t spend that long down there but it is potentially very worrying for train drivers or maintenance staff. The concentrations are very high even compared to somewhere like Oxford Street.’
TfL challenged the findings, saying people face ‘high concentrations’ of PM2.5 at home, especially when cooking, and from exhaust fumes above ground.
Safety chief Lilli Matson said TfL spends £60million a year cleaning and monitors ‘to ensure that particle levels are well within Health and Safety Executive guidelines’. It has also commissioned new research.