Ninety-four percent of hospitals in London contain asbestos, according to an article on the BBC website.
About 1,000 people have died from mesothelioma since 2011 in London, seven of which were doctors and nurses.
The government said many parts of the NHS estate date from an era when asbestos was widely used but it is considered safe if left undisturbed. The Health and Safety Executive also claims that white asbestos — the type used in hospitals — does not pose a risk.
But experts described the number of people who are developing mesothelioma as like a "ticking time bomb".