New research from the University of Southampton has revealed that working or travelling on the Tube could be bad for your health.
Experts say the small dust particles in the air at underground railway stations differ from the dust breathed in every day and these could have health implications, affecting the brain, liver and kidneys.
PhD student Matt Loxham, at the University of Southampton, explains: "We studied the ultrafine dust found in an underground station in Europe. Typically, ultrafine dust is composed of inert matter that does not pose much of a risk in terms of its chemical composition.
"However, in the underground station we studied, the ultrafine dust was at least as rich in metals as the larger dust particles and therefore, taken together with their increased surface area to volume ratio, it is of potential significance in understanding the risks of working and travelling in the underground. These tiny dust particles have the potential to penetrate the lungs and the body more easily, posing a risk to someone's health."
Mr Loxham added: "Underground rail travel is used by great numbers of people in large cities all over the world, for example, almost 1.2 billion journeys are made per year on the London Underground.
"The high level of mechanical activity in underground railways, along with very high temperatures is key in the generation of this metal-rich dust, and the number of people likely to be exposed means that more studies into the effects of particulate matter in the underground railway environment are needed, as well as examining how the levels of dust and duration of exposure might translate to effects on health."
Meanwhile, London Underground's Chief Operating Officer, Howard Collins, told the Evening Standard: "We have carried out monitoring of dust levels on the Tube for many years to re-assure our passengers and staff. That research has consistently shown that mineral levels within the dust are perfectly safe and that dust levels are less than a third of the limit set by the Health and Safety Executive for general dust.
"That standard remains the level required by the Health and Safety Executive and would be amended if they felt there was any danger to our passengers or staff.
He adds: "It is clearly wrong to attempt to draw any conclusions about London Underground from this new research that studies one station elsewhere in Europe."
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