Professor Julian Peto says taking out the asbestos would lead to the release of more deadly fibres than leaving it undisturbed.
A leading cancer expert says a campaign to get asbestos removed from all schools in the UK is unnecessary and could cause more deaths.
Trade unions want the government to spend billions of pounds to take asbestos out of schools, echoing a 2015 report by MPs calling for the removal of asbestos from every workplace.
But Professor Julian Peto, Britain’s leading expert on asbestos cancers, has told Sky News that much of the most dangerous asbestos has already been removed and trying to take out the remainder is not advisable because it would release more fibres.
“It isn’t clear to me that the exposures are high enough,” he said.
“And in particular it isn’t clear to me that to do something about it wouldn’t increase the risk.”
Asbestos was used for insulation and fire protection but was banned in 1999 because it can cause a range of diseases decades after being breathed in, including mesothelioma – a fatal lung cancer.
Professor Peto, Cancer Research UK Chair of Epidemiology at the London School of Hygiene and Tropical Medicine and the Institute of Cancer Research, says the risk of dying from mesothelioma depends on when you were born and whether you worked indoors or outdoors.