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Wireless networks — known as Wi-Fi or wLAN (wireless local area
network) — are increasingly used in schools, offices and other public places to connect computers and laptops
to the internet using radiofrequency transmitters with no need for complex cabling. In future, whole town
centres will be transformed into wi-fi “hot spots”, enabling people to access the internet wherever they are
through hand-held devices, including mobile phones. Indeed, Milton Keynes, Norwich and the borough of
Islington, in North London, already have this WiMax technology.
It has taken the public a while to wake up to the idea that wireless
transmitters could be less than benign. As with mobile phones, we first embrace the liberating new
technology and only later ask the awkward questions. Perhaps, as with pharmaceuticals, the order should be
reversed. The official line on the health implications of wi-fi is that exposure to low level
electromagnetic radiation from wireless networks is well below recommended levels and that there is no evidence
of risk. But despite these soothing words, the groundswell of concern is mounting, with some people
blaming everything from headaches to cancer on exposure to radio-frequency fields.
As reported in this newspaper, a number of schools have dismantled
their wireless networks after lobbying from worried parents, and others are under pressure to follow suit.
In Austria the public health department of Salzburg has advised schools and kindergartens not to use wLAN or
cordless phones.
Lakehead University in Ontario, Canada, which has 7,400 students, has removed wi-fi because of what its
Vice-Chancellor, Dr Fred Gilbert, calls “the weight of evidence demonstrating behavioural effects and
physiological impacts at the tissue, cellular and cell level”.
Some experts have also expressed concerns. In September, 30
scientists from all over the world signed a resolution calling for a “full and independent review of the
scientific evidence that points to hazards from current electromagnetic field exposure conditions worldwide.”
Closer to home, the Irish Doctors Environmental Association (IDEA) has asked its country’s Government to carry
out “a full assessment of the health impacts of electromagnetic radiation”.
“There has been no research specifically looking at the effects of
wireless networks on human health,” admits Alasdair Philips, the scientific and technical director of the
lobby group Powerwatch. “But I have seen enough anecdotal material to be convinced that some people are
affected by them.”
David Dean, 43, a councillor in Merton, South London, and the
managing director of a publishing company, describes himself as a human antenna. “The moment I go into
people’s houses I know whether they have wi-fi because my head starts to buzz. I had to leave my last
job because I couldn’t stand up for more than ten minutes in the office and my boss would not remove the
wi-fi. My heart raced, I had double vision and really bad headaches. It felt as though my head was in an
arm lock. Twice I have been into homes where the children were screaming monsters. After I suggested
to the parents that they turn off the network for two days, the kids were transformed.”
Anxiety about wi-fi has focused on the effect of electromagnetic
radiation on children because they have thinner skulls, less fully developed nervous systems and will undergo a
lifetime of exposure to cellphone technology. In his report on mobile phones, Professor Sir William
Stewart, the chairman of the Health Protection Agency (HPA), acknowledged that radiation below guideline levels,
while thought to be safe, may have effects on the body. He therefore advocated a precautionary approach,
including close monitoring of radiation from masts near schools and a recommendation that the beam of greatest
intensity from a mast should not fall within the grounds of a school.
“The emissions from wireless networks are very similar to those
from mobile phone base stations in terms of frequency and signal modulation,” says Philips, who, it must be
said, runs a company selling electromagnetic radiation detectors and blockers. “Many published reports
have shown ill-health affects apparently associated with living and working close to mobile phone masts.
In a Latvian study of 966 children, motor function, memory and attention were significantly worse in the group
exposed to radiation from a pulsed radio location station. The exposure levels were low, but similar to
those that children in classes with wLANs will be exposed to.”
Dr Michael Clark, of the HPA, says published research on mobile
phones and masts does not add up to an indictment of wi-fi. “All the expert reviews done here and abroad
indicate that there is unlikely to be a health risk from wireless networks,” he says. “The few studies
on mobile phone masts that have appeared in peer-reviewed journals claiming to observe health effects are not at
all conclusive. The real problem is deciding what level of precaution is appropriate.
“When we have conducted measurements in schools, typical exposures
from wi-fi are around 20 millionths of the international guideline levels of exposure to radiation. As a
comparison, a child on a mobile phone receives up to 50 per cent of guideline levels. So a year sitting in
a classroom near a wireless network is roughly equivalent to 20 minutes on a mobile. If wi-fi should be
taken out of schools, then the mobile phone network should be shut down, too — and FM radio and TV, as the
strength of their signals is similar to that from wi-fi in classrooms.”
Philips is not reassured: “Electromagnetic radiation exposure
guidelines in the UK are designed to protect against gross heating effects. They are not meant to protect
against long-term exposure to low levels of pulsing microwaves, such as laptops emit when downloading. We
believe that these interfere with the body’s own normal internal electrical and electro-chemical signalling
systems, leading to serious health problems, and growing children may be more affected than adults, whose cells
are not changing as rapidly.”
One of the problems in conducting research is that not everybody is
affected by electromagnetic radiation in the same way. “A growing, consistent body of literature
demonstrates that a subgroup of the population appears to suffer distressing symptoms when exposed to this type
of radiation,” says Dr Elizabeth Cullen, of IDEA. Sleep disturbances, depression, blurred vision, heart
and breathing problems, nausea and headache are among the most common symptoms.
Up to 5 per cent of the population is thought to have this
sensitivity, which is recognised in Sweden as a disability. In Stockholm sufferers can have their homes
adapted to remove or screen out sources of electromagnetic radiation. If this proves ineffective, they can
even rent council-owned cottages in areas of low radiation.
However, Dr Clark is not persuaded that electromagnetic fields are
the cause of sensitivity. “While we accept that some people experience genuine symptoms, which can be
distressing, what causes them is another matter. Most scientists are very sceptical because of the
published laboratory investigations of electrosensitivity. People who are convinced that they can tell
when they are in the presence of electromagnetic radiation cannot detect the fields in double-blind laboratory
conditions.”
An important study by the University of Essex, due to be published
next year in a peer-reviewed journal, may settle the matter. During the trial, 55 people who believe that
they are hypersensitive and 120 non-sensitive controls were subjected to tests of concentration and memory while
signals from second and third generation mobile phone masts were switched on and off. The trial was double
blind: neither the researchers nor the subjects knew when the signals were firing.
Some believe that sensitivity symptoms are not the only threat posed
by electromagnetic radiation. A Swedish study suggests that there is an increased risk of acoustic neuroma
(an auditory nerve cancer) in people who have used mobile phones for more than ten years. Conversely, last
week the results of the largest and longest-running study on mobile phones and the risk of cancer, published in
the Journal of the National Cancer Institute, found that there was no link.
A literature review conducted by the International Commission for
Non-Ionising Radiation Protection concluded: “Results of epidemiologic studies to date give no consistent or
convincing evidence of a causal relation between exposure from radio frequency fields (RFs) and any adverse
health effect. On the other hand, these studies have too many deficiencies to rule out an
association. Despite the ubiquity of new technologies using radio frequency fields, little is known about
population exposure from RF sources, and even less about the relative importance of different sources.”
And here lies the nub of the problem. Not enough research has
been done over long enough periods on the effects of various levels of exposure on different populations to draw
any firm conclusions about the dangers, if any, of wireless networks. As to whether the convenience is
worth the risk – only you can decide.
‘I FELT DIZZY AND NAUSEOUS’
“Electrosensitivity” is a rather misleading term. I’m
fine around electricity. But put me next to a BlackBerry or a wireless laptop accessing the internet and I
feel dizzy, slightly nauseous and my flesh tingles as if it’s being scrambled. It sounds bonkers I
know. But after years of denial I have had to come to terms with the fact that aspects of this fantastic
new technology do not agree with me.
We installed wi-fi in our house two years ago. We loved
it. The whole family could be online at the same time. I imagined myself working in the garden
during the summer (although I never did), and I could work in bed. But from the moment wi-fi arrived I
felt peculiar.
I mentioned casually to my husband that I could tell when he was
sending an e-mail, but he dismissed that as laughable: I must be imagining it. So I put the idea out of my
mind. But as the weeks and months passed I began to feel iller, overwhelmed at times by intense giddiness,
headaches and a sense that I was moving through a dense fog. Sleep was fitful and I seemed to feel
constantly at a low par.
Then we went away for the Easter break to stay with friends in the
depths of remote countryside. I felt great as you tend to do when you’re on holiday. But the
moment we walked back into our house I felt giddy and nauseous again and then I knew. I wasn’t neurotic.
This was real.
I changed our router back to wired internet access. I had the
computers reconfigured so that they no longer sent out signals searching for wi-fi and we binned the dect phones
(digital cordless phones) just to make doubly sure. My husband began to notice the change in me within days and,
finally, he believed me.
The trouble is that you can’t talk about this without people
thinking that you’re mad. My symptoms are minor compared to others I have heard of. Sometimes I
notice wi-fi in the wider world when it’s heavy — my local bookshop, the Apple Mac shop, airports and an
expensive hotel we recently went to stay in. Other times I feel this scrambled fog only when I’m near a
device using this technology — the hand-held machine in restaurants that you tap your pin number into and
laptops surfing the web.
After months of monitoring, I’m happy knowing that it is wi-fi that
makes me feel this odd and not some other unknown disease. I avoid it when I can. I don’t see much
difference between someone smoking a cigarette or shouting into a mobile phone next to me in a public
place. If anything I think I’d prefer the cigarette.
Poppy Rhodes |
