“Air pollution can harm acutely, as well as chronically, potentially affecting every organ in the body,” conclude the scientists from the Forum of International Respiratory Societies in the two review papers, published in the journal Chest. “Ultrafine particles pass through the [lungs], are readily picked up by cells, and carried via the bloodstream to expose virtually all cells in the body.”

Prof Dean Schraufnagel, at the University of Illinois at Chicago and who led the reviews, said: “I wouldn’t be surprised if almost every organ was affected. If something is missing [from the review] it is probably because there was no research yet.”

The review represents “very strong science”, said Dr Maria Neira, WHO director of public and environmental health: “It adds to the very heavy evidence we have already. There are more than 70,000 scientific papers to demonstrate that air pollution is affecting our health.”