London Underground ‘polluted’ with metallic particles that can enter bloodstream

The London Underground is “polluted” with ultrafine metallic particles that are small enough to enter passengers’ bloodstream.

A new study by Cambridge University says high levels of iron oxide, called maghemite, are thrown into the air by the grinding of wheels, tracks, and brakes.

These fragments have previously been linked to cancer, dementia, and cardiovascular disease, but the study outlines it “not clear whether these particles pose a health risk.”

The particles are so small, the report says, that they’re likely being “underestimated” in surveys of pollution in the tube.

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