In the past 18 months 1.6million wi-fi connections have been set up in the UK. This means children using computers at home could also be at risk.
The World Health Organisation, backed by the Government, says there are ‘no adverse health effects from low-level, long-term exposure’ to wi-fi radiation.
But Sir William said there was growing evidence of possible harm from radio-frequency radiation.
He explained: ‘There may be changes, for example in cognitive function.
‘There were some indications that there may be cancer inductions. There was some molecular biology changes within the cell.’
Philip Parkin, general secretary of the Professional Association of Teachers, said: ‘I am asking for schools to consider very seriously whether they should be installing wi-fi networks now and this will make them think twice or three times before they do it.’
The levels of radiation Panorama found were 600 times lower than those deemed dangerous by the Government, which bases its data on radiation safety limits provided by a group of scientists called ICNIRP.
But it does not take the biological effects of radio-frequency radiation into account, basing exposure limits solely on a ‘thermal effect’.
This means radiation only counts if it is so strong it causes a heat effect.
Sri Lanka, Colombo,
Mongolia, Ulan Bator,
Dominican Republic, Santo Domingo
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