(IME 2007 - Adaptada)
Wi-Fi? Why Worry? (Adapted from BBC, April 2007)
Scare stories about the dangers of wireless networks lack credibility, argues Bill Thompson
1 Students at Canada"s Lakehead University have to be careful how they connect to the internet
because Wi-Fi is banned on large parts of the campus.
2 University president Fred Gilbert, whose academic interests include wildlife management,
environmental studies and natural resources science, is worried about the health impact of the
2.4 GHz radio waves used by wireless networks
3 Last year he decided to adopt the precautionary principle and refused to allow Wi-Fi in those areas
that have what he calls "hard wire connectivity" until it is proved to be safe.
4 Mr Gilbert believes that "microwave radiation in the frequency range of Wi-Fi has been shown to
increase permeability of the blood-brain barrier, cause behavioural changes, alter cognitive
functions, activate a stress response, interfere with brain waves, cell growth, cell communication,
calcium ion balance, etc., and cause single and double strand DNA breaks".
5 Unfortunately the science says he is wrong, and his students are suffering as a result.
Smog talk
6 While the heating effects of high exposures to electromagnetic radiation can be damaging, the
power levels of wireless connections are much lower than the microwave ovens and mobile phones
which share the frequency range, and treating them in the same way is the worst sort of
scaremongering.
7 Yet Mr Gilbert is not alone.
8 In 2003 parents sued a primary school in Chicago because it had dared to provide children with
easy access to computing resources over a wireless network.
9 And there are a number of pressure groups, campaigning organisations and ill-informed individuals
who believe that wireless networks pose a threat to health and want to see them closed down.
10 Now it seems they have been joined by the editor of the UK newspaper the Independent on Sunday,
which this weekend filled its front page with a call for research into the "electronic smog" that is
permeating the nation"s schools and damaging growing children"s brains.
11 An accompanying editorial with the even-handed headline "high-tech horrors" called for an official
inquiry, while the article outlining the perceived dangers asked "Is the Wi-Fi revolution a health time
bomb?"
12 The answer, of course, is "no".
13 That will not stop the newspaper stoking up a wave of opposition to one of the most liberating
technologies to have come out of the hi-tech revolution, limiting children"s access to networked
computers at schools and even blocking plans to develop municipal wireless networks in our towns
and cities.
14 If the journalists were really concerned about the dangers of radio frequency electromagnetic
radiation on the sensitive brains of the young, they should be calling for the closure of TV and radio
transmission towers rather than asking us to turn off our Wi-Fi laptops.
15 The modulated frequencies that carry Radio 4 and ITV into our homes are just as powerful as the
wireless networks, and a lot more pervasive.
16 And my wireless network is only carrying data when im online, while Radio 3 burbles all day long,
possibly exciting electrons in my brain and causing headaches.
17 Then there is the danger from photons of visible light streaming down onto us as we work, since
these carry more energy than microwaves and could surely do more damage.
18 Perhaps we should demand that our children work in the dark.
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What critics does the author of the text make against Fred Gilbert? Support your answer.
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