Panorama: Wi-Fi – A Warning Signal
Wi-fi networks in schools can give off three times the height of the
signal radiation of phone masts, a BBC Panorama investigation has discovered.
The Chairman of the Health Protection Agency, Sir William Stewart, calls
for a review of the health effects of wi-fi in the programme, to be
broadcast tonight on BBC One.
Current Government advice – from a report published by Sir William in
2000 – recommends that phone masts are not sited near schools, without
consultation with parents and the school, because children are thought to
be more vulnerable to radio frequency radiation emissions than adults.
Panorama visited a comprehensive school in Norwich and measured the
radiation signal strength from a classroom wi-fi enabled laptop.
programme found the height of the signal strength was three-times higher
than the height of the signal strength of a typical phone mast.
Children's skulls are still growing and are thinner than adults' – tests
have shown children absorb more radiation than adults when using mobile
phones – which could raise questions about the safety of children working
bent over computers being exposed to radiation at very close-quarters.
The school Panorama visited had nine classrooms with wi-fi nodes in operation,
with plans for more.
Seventy per cent of secondary schools in the UK already have wi-fi and nearly 50% of
all primary schools do.
Panorama spoke to nearly 50 of those schools and
only one had been alerted that there might be possible health risks. Some
others had been told that there was no risk.
Sir William Stewart, scientific adviser to the last three governments,
says: "I believe that there is a need for a review of the wi-fi and other
areas... I think it's timely for it to be done now."
Philip Parkin, General Secretary of the Professional Association of
says: "I think schools and parents will be very worried about it...
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 Government says there is no health risk from wi-fi.
It cites the
World Health Organisation's view which states there are "no adverse health effects from low level, long-term exposure".
However, Sir William believes they are wrong to stick to that statement: "There is evidence and the Stewart report pointed out some of that
In 2000 Sir William was commissioned to produce a report to examine
mobile phones, masts and health.
Speaking about the findings of that
report, in relation to mobile phones, masts and health, he says: "... 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 and these were issues that we
had to bear in mind."
The levels of radiation Panorama found in the Norwich classroom are 600
times lower than the levels deemed dangerous by the Government.
Government relies on the data supplied by ICNIRP, an international group
of scientists, for radiation safety limits.
However ICNIRP does not take into account biological effects of radio
frequency radiation and bases exposure limits on a thermal effect.
other words, the radiation has to be so strong it causes a heat affect
before it is restricted.
Professor Henry Lai of Washington University is a biologist respected by
both sides of the argument.
He did his own review of all the experiments
on mobile phone to see how many found an effect. He has found health
effects at similar levels of radiation to wi-fi in over 30 years of
says: "I think it's about 50-50; 50% found an effect and 50% did not find an
effect at all."
"I think it's irresponsible to just set standards using a thermal
standard... if you set it just based on a thermal effect you are
neglecting a large amount of data."
Dr Olle Johansson of the world-renowned Karolinska Institute in Sweden
has also carried out experiments on radiation similar or lower than wi-fi
and found biological effects.
When asked if the ICNIRP is right to set limits based on thermal effect,
the doctor says: "That's just rubbish, I would say, you know. You cannot, er, put any er,
emphasis on such guidelines."
Panorama asked the Government for an interview on the issue but was
referred back to the Health Protection Agency, the Chairman of which is
Sir William Stewart, the man who has told Panorama he is uncomfortable
with the speed with which wi-fi is being rolled out.
Panorama: Wi-Fi – A Warning Signal, Monday 21 May 2007, 8.30pm, BBC One
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