After cancer warnings on mobiles, could your home phone be putting your health in danger?
By TESSA THOMAS – Last updated at 22:57pm on 18th February 2008
Like many of us, David Dean enjoyed the freedom a digital cordless phone gave him to walk about the house while on calls.
Then the 44-year-old company director from Wimbledon started getting headaches – when he stopped using his cordless phone the headaches went overnight.
There has been much controversy over health problems linked to mobile phones and masts. Only this week, a new report – based on research revealed in the Mail last year – claimed that people who use a mobile phone for hours a day are 50 per cent more likely to develop mouth cancer.
But some experts believe that digital wireless phones – used in millions of homes – could be just as problematic.
These phones operate using the same technology as wi-fi computer systems and mobile phones – with the base station acting like a miniature mobile phone mast.
A recent survey by the Dutch Electrohypersensitivity Foundation has found that digitally enhanced cordless telephones – Dects – are the main source of radiation in homes that have them.
The researchers claimed that they frequently cause headaches, fatigue, heart palpitations and concentration and sleep problems.
According to cancer specialist Professor Lennart Hardell from the University Hospital, in Orebro, Sweden: “The risks are the same as for mobiles, but they haven’t been studied because researchers thought the Dect operated like a landline.”
One of the few scientists to have included cordless phones in his studies, Professor Hardell’s research suggests that habitual users have a three-fold risk of acoustic neuroma (a benign tumour between the ear and brain) and a four-fold risk of a malignant brain tumour.
But other experts dispute his findings.
A Dect phone sits in a cradle on a base that charges it up between calls.
“Although people treat a Dect phone as if it’s an ordinary landline, its base station constantly emits radiation, so the health risks are the same as for a regularly used mobile,” says Professor Hardell.
It is not only their constant output that elevates these risks, he says. “They are usually in rooms where people spend a lot of time and people tend to spend longer on them than they do on a mobile.”
According to Dr Andrew Goldsworthy, an honorary lecturer in biology at Imperial College London: “The effect is you have a double whammy, because the base station is powering up 24-hours-a-day and the handset is picking up and sending signals whenever it’s held to the head.”
The signal can travel though walls and ceilings, too.
Ron Butlin, a 58-year-old novelist, from Edinburgh, had already been suffering from mild heart palpitations when he got a Dect phone. But in a matter of weeks, they became severe.
“I was rushed to hospital and put on various drugs until they found a combination that worked, fortunately – but it was frightening.”
He got rid of the Dect phone and has had no palpitations since.
So what is going on? Goldsworthy believes that the microwave signals from the phone weaken cell membranes, which then leak. Enzymes can then get into the cell and start digesting it.
In Germany, hundreds of doctors signed a petition calling for a ban on Dect phones in public places.
The German Federal Agency for Radiation Protection has backed this with a warning that Dect devices, “have no control to regulate power output according to the power needed”.
In Europe, you can now now buy digital cordless phones that do not emit microwaves when on standby. But in Britain, the response is more conservative.
Dismissing studies like Hardell’s a a one-off, the Health Protection Agency – which advises the UK Government on radiation issues – argues that as a Dect signal is weak, it is not harmful.
“Only the base station unit in a Dect system is operating like a mast and the health risks around it are no greater than from a mobile mast,” says the HPA’s Dr Michael Clark.
However, critics say that it is not the signal strength that matters. One of the worries is that the radiowaves are pulsed, coming in sharp intermittent bursts that can disrupt the brain’s signalling.
The two sides do agree that a Dect base station is constantly emitting, like a mini phone mast in the home.
The HPA has advised manufacturers that base units need not be designed to be on all the time.
“But it’s an international industry standard and we can’t regulate,” says Dr Clark.
They also agree that exposure of children is a concern, as their developing tissues are more susceptible to damage.
The Government recommends that under-eights should not use mobile phones at all and under-16s only for “essential calls”. The HPA says that although, “there is no clear evidence of harm from cordless phones, parents can take a precautionary approach and prevent children using them”.
Christine Garnier, a 45-year old company bookkeeper from Jersey, has no doubt this is a good idea.
She had two cordless phones in her house when a local protest against a mobile mast made her think again about the technology she used. She got rid of them, “and within 24 hours I felt a sort of pressure in my head go. But the real change was in Thomas”.
Her six-year-old son had been having sleep problems, often said he felt sick after being in the house after school and was temperamental. “As soon as I got rid of the phones, he became calmer and slept much better.”
Dr Goldsworthy believes that “probably everyone is being affected to some degree”.
Others say that only “electrosensitive” people are significantly affected and, although their resulting conditions can be serious, they account for only three per cent of the population.
Professor Hardell claims that, whatever the disagreement over the source or severity of short-term symptoms, in the longer term, “we can expect an increase in diseases such as Alzheimer’s and Parkinson’s due to neurological damage and tumours.”
While there is no consensus on the degree of risk from mobile and Dect apparatus, both sides recognise that the UK’s accepted exposure limit is the highest in Europe.
At the Human Health in an Electro-Technological World conference where Professor Hardell presented his findings last November, the scientists who helped set these levels were roundly criticised. David Dean, among others, is quietly applauding.