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Éxcelente artículo en la revista americana ODE

How dangerous is my mobile?

Martes 19 de diciembre de 2006 · 1681 lecturas




How dangerous is my mobile?

Kim Ridley
This article appeared in Ode issue: 39

growing body of research suggests that radiation from cellphones and other electronic devices may harm our health. How worried should we be and what can we do about it?

Perhaps more than any other technology, wireless communication is incredibly seductive and increasingly cheap. We can gab on our cellphones for hours, thanks to gazillions of “free minutes”; keep up with our email from practically anywhere on our BlackBerries; and Wi-Fi our way around the planet free. These technologies “connect” us like never before. But like many things sexy and cheap, there’s a downside.
All wireless devices-from cellphones to “CrackBerries”- contribute to rising levels of electronic smog, an invisible miasma of electromagnetic radiation blanketing the planet. Consisting mainly of radio frequency (RF) radiation emitted by wireless technologies and electromagnetic fields (EMFs) emanating from power lines and anything electrical, electronic smog is likely the fastest-growing form of pollution today. We may be exposed to one trillion times more electromagnetic radiation than our ancestors were 150 years ago.
This sounds unbelievable until you consider that levels of RF alone have skyrocketed over the past two decades since the advent of cellphones. An estimated 2.5 billion cellphones are in use around the planet, along with more than 1.3 million base station antennas installed on towers and rooftops around the world. Levels of RF will continue to rise as Wi-Fi, WiMax and other wireless technologies proliferate. We are altering our environment in unprecedented ways.
How much should we worry? It depends on whom you ask. While many studies have found no ill effects from electronic smog, some scientists say their research raises concerns. Many of these findings implicate cellphones. The radiation that makes the marvels of wireless communication possible may also harm our health.
Researchers around the world are reporting that cellphone radiation can affect everything from the electrical activity of the brain to cell function. Scientists in Europe and the former Soviet Union have reported associations between RF and a host of human ailments, including headaches, fatigue, learning and memory problems, sleep disturbances, disruption of immune and hormonal systems and brain tumours. Animal studies have found that RF can make the blood-brain barrier more permeable and actually break strands of DNA-potentially damaging the blueprints of life itself.
As compelling as these findings are, however, they don’t conclusively prove that RF causes health problems, a valid point that the telecommunications industry repeatedly makes. Of course, it would. Any industry says “prove it” when people raise concerns over possible health effects of new substances or technologies. In the past, society has often paid the price.
“If we wait for definitive proof, we’re back in the days when the tobacco industry was able to hold off regulations for years by claiming that there was no conclusive evidence that cigarette smoking causes lung cancer,” says Cindy Sage, a California EMF expert. “It’s just like any other argument about a potential carcinogen. The question is, do we take reasonable precautions now or do we wait 30 years until the industry has to admit there is proof and we’ve lost another generation or two?”
Sage is among scientists around the world who say the weight of evidence is powerful enough to take practical measures right now to protect ourselves from electromagnetic exposure. In the absence of certainty, they are urging precaution. Their recommendations are largely based on the precautionary principle, a policy-making tool that involves choosing the safest alternative to any technology, chemical or activity that poses potential harm, even in the absence of scientific certainty.
In September, 31 scientists from 13 countries signed the Benevento Resolution, a new international call for independent research and increased measures to protect the public from hazardous exposure to all forms of electromagnetic radiation. But as alarming as that sounds, you don’t need to jettison your cellphone. Not yet, anyway.

Don’t safety standards for wireless communications technologies already exist? Yes, but a number of researchers say these standards are outdated and inadequate. A growing body of evidence supports that contention.
The RF radiation emitted by wireless devices, as well as EMFs from power lines and all electrical equipment, are forms of non-ionizing radiation that is too weak to break chemical bonds. The World Health Organization (WHO) and governments around the world set safety standards below levels at which this radiation can heat or burn tissue. These standards are based on the assumption that if the radiation can’t “cook” you, it can’t hurt you.
Among the first to challenge this assumption in a big way was American epidemiologist Nancy Wertheimer. When children in Denver, Colorado, experienced higher-than-average rates of leukemia in the 1970s, Wertheimer went looking for answers. What she found shocked her and sparked a controversy that still rages.
Wertheimer and physicist Ed Leeper reported in 1979 that the children who lived closest to electrical transformer boxes were two to three times more likely to die of cancer, particularly leukemia and brain cancer, than children living farther away. Subsequent findings from studies elsewhere in the world have been mixed, but this summer, Japanese scientists again found a possible link between EMF exposure and childhood leukemia.
Though controversial, Wertheimer’s findings broke new ground for research on potential health effects of EMFs and RF radiation that continues today. “If you believe there is a link between EMFs and childhood leukemia, you have to accept that some type of biophysical interaction is going on,” says Louis Slesin, Ph.D., who has reported on non-ionizing radiation for 25 years as editor of Microwave News. “And then you have to ask the question: ‘What else may be happening?’ Once you allow that the ‘impossible’ is possible, you have to take the other potential effects seriously.”
In the years since Wertheimer’s work in Colorado, researchers have found possible connections between EMFs and a number of cancers. “Electromagnetic fields can affect many different body systems, and the relationships are complicated,” notes B. Blake Levitt, author of Electromagnetic Fields: A Consumer’s Guide to the Issues and How to Protect Ourselves. “Researchers are finding statistically significant increases in leukemia, brain cancers, melanoma and male breast cancer. The increases on average are small-between 1 and 5 percent-but whenever a consistent pattern above the expected appears, it is generally considered important, and often the tip of the iceberg.”
Today, some researchers suspect that EMFs and RF radiation may trigger other illnesses and symptoms in the estimated 3 to 30 percent of people who are sensitive to electronic smog. These “electro-sensitives” report symptoms ranging from headaches and sleep disturbances to confusion and chronic fatigue. Some say their conditions are so debilitating that they’ve had to quit their jobs and, in the worst cases, live without electricity.
EMFs from “dirty electricity” also may contribute to chronic illnesses including diabetes and multiple sclerosis, according to Magda Havas, a professor of environmental and resource studies at Trent University in Peterborough, Canada. Although her studies so far are small, her preliminary findings are provocative.
Havas defines dirty electricity as a mishmash of electromagnetic signals ranging from RF radiation from base stations to surges from home electronics that course through electrical wiring. It’s a problem that can be fixed in industrial and office settings by using large capacitators to filter out polluting frequencies. But that’s hardly ever done in the home. Havas has been testing the Graham/Stetzer filter, developed for residential use, in the homes of people with chronic illness.
At first, Havas herself couldn’t believe some of her findings. She reported that cleaning up the electrical environments of a portion of people with diabetes reduced their symptoms. In some cases, diabetics’ fasting blood-sugar levels dropped so dramatically that many required less insulin. She found similarly surprising results in the homes of a few people with multiple sclerosis. In one case, a man in his late 20s with progressive MS was able to walk without a cane after the dirty electricity in his home was filtered.
Havas-who receives no funding from Stetzer Electric, the company that distributes the filters-is quick to point out that she has studied only small numbers of people-20 diabetics so far and a few more people with MS-and that many do not experience any improvement in their symptoms after their homes are electrically cleaned. She hypothesizes that those who do respond are electrically hypersensitive. She presented case studies at a WHO workshop on electro-hypersensitivity in Prague in 2004. She calls diabetics whose symptoms improve after electrical filters are installed “type 3 diabetics” and is submitting a paper on her findings to international scientific journals.

While the health effects of EMFs remain uncertain, concern has shifted in recent years to the potential dangers of RF radiation accompanying the rise of wireless technology. The main issue: Every time you use a cellphone handset, you’re planting a microwave antenna next to your brain.
Cellphone radiation isn’t strong enough to fry your grey matter, but it might do damage in other ways. How could such weak radiation possibly harm us? No one knows exactly. What is known is that certain frequencies of electromagnetic radiation interact more directly with living organisms and even disrupt them, just as cellphone radiation can interfere with an airplane’s navigation system. In addition, some scientists are finding that the pulsed digital RF used by newer cellphones and cordless phones may have greater biological effects. It turns out that our bodies are finely tuned instruments.
Human beings most readily absorb frequencies in the FM radio and VHF television bands, but radios and TVs are passive receivers and don’t pose a health threat (living right next to a powerful broadcast transmitter, however, may be another matter). Cellphones and other wireless technologies use higher radio frequencies on the electromagnetic spectrum, including the microwave band. The higher the frequency, the shorter the wavelength. The shorter the wavelength, the more easily the body absorbs the energy and the more likely the biological effects.
One of the first scientists to demonstrate biological effects of cellphone radiation was Henry Lai, a bioengineering professor at the University of Washington in Seattle. Lai and his colleague Narendra Singh have reported that mobile phone radiation can break strands of DNA in the brain cells of rats. They observed this effect after the rats were exposed for only two hours.
Lai hypothesizes that cellphone radiation breaks DNA strands by increasing the formation of free radicals in exposed tissue. These unstable molecules are believed to damage cells and DNA in a process that may underlie everything from cancer to aging. If Lai is correct, the implications are huge. If not properly healed, DNA damage in neurons can give rise to cancer and has been linked with Alzheimer’s, Parkinson’s and neurodegenerative diseases.
“The largest human biological experiment ever” is how Dr. Leif Salford, chairman of the department of neurosurgery at Lund University Hospital in Sweden, describes global exposure to RF radiation.

What worries most people is whether or not cellphones cause brain tumours. Many studies have found no association with brain tumours. Two teams in Sweden, however, have reported that heavy use of cellphones for more than 10 years increases the risk of acoustic neuroma, a benign tumour of the auditory nerve. One of the groups, led by professor Lennart Hardell of Öreboro University and Kjell Hansson Mild of the National Institute for Working Life, also found a higher risk of brain tumours associated with heavy use of cellphones or cordless phones for more than a decade.
Concern is also rising over the possible health effects from cellphone base stations. Although exposure to RF radiation from a cellphone is about 1,000 times higher because you press the phone against your head, people who live near base stations are exposed 24/7.
Some people who live near base stations, particularly in Europe, are reporting health problems. Researchers in France, Germany, Austria and elsewhere have investigated these “clusters” and some have found higher rates of sleep disturbances, fatigue and headaches. The French group found that symptoms were worse among those living within 100 metres, with many subjects also reporting problems including depression, memory loss, irritability, dizziness and nausea.
Are such findings mere coincidences? It’s too soon to jump to that conclusion, says Dr. Michael Kundi, an epidemiologist at the Medical University of Vienna who has investigated potential EMF health effects for decades. “Even though there might be a chance relationship between base stations and some diseases occurring near them, I think we have to take people’s symptoms seriously,” Kundi says. “There also needs to be an investigation into possible relationships between base stations and the development of chronic disease. It would be complicated, but it can and should be done.”

The kinds of studies Kundi and many of his colleagues want to see, however, would take years to complete, especially given that independent funding for this kind of work is rare in Europe and non-existent in the U.S. Like many other industries, the $570 billion mobile phone market has a powerful influence on research.
How much of an influence? Anke Huss and Matthias Egger of the Institute of Social and Preventive Medicine in Berne, Switzerland, recently examined that question, reviewing findings from 59 studies on the health effects of mobile-phone use based on funding sources. In a paper published in Environmental Health Perspectives (September 2006), the researchers report that “studies exclusively funded by industry were indeed substantially less likely to report statistically significant effects on a range of end points that may be relevant to health.” They conclude: “The interpretation of results from studies of health effects of radio frequency radiation should take sponsorship into account.”
Industry’s influence on research is one of the main issues that scientists signing the Benevento Resolution want to change. The resolution calls for independently funded and publicly monitored research on the potential effects of EMFs and RF radiation, which in turn will inform the best strategies to protect public health.
As of today, only a handful of countries have policies to minimize public exposure to non-ionizing radiation. Italy, Switzerland and Luxembourg have implemented the strongest measures, and Greece and Israel have adopted less-stringent guidelines. Switzerland, which in 1983 applied the precautionary principle to all environmental laws, passed legislation in 1999 regulating emissions of non-ionizing radiation from all stationary sources including power-transmission lines and cellphone base stations.
Swiss law regulates the construction of mobile phone base stations contingent on maximum exposure levels of 4 to 6 volts per metre in “sensitive locations” such as homes, schools, businesses and playgrounds. Before installing a new station, a cellphone company must apply for a permit and include precise calculations demonstrating that the RF radiation doesn’t exceed the legal limit. The application is then submitted for review by the local government authority and made available for public comment. If calculations show that RF levels approach 80 percent of the limit, the local authority will usually require radiation measurements by an independent agency after the base station is installed. The company must turn down the power if the base station exceeds radiation limits.
Although Switzerland’s precautionary approach initially met with resistance from industry, that’s no longer the case, says Jürg Baumann, head of the non-ionizing radiation section of the Swiss Agency for the Environment. “There is a broad acceptance in all concerned circles that if there might be negative effects from this technology, we should deal with them,” Baumann says. “Before this, preliminary reports and findings were simply ignored by those who didn’t want to listen to them.”
Why aren’t more countries following the example of Switzerland and other nations that have adopted a pre-emptive approach? Baumann says they’re probably waiting for new recommendations from the WHO, which still bases safety guidelines on radiation levels that can heat or burn tissue. He says he doubts that the WHO will change its position any time soon for fear that recommending further reductions would call the current guidelines into question.

The 31 scientists who signed the Benevento Resolution aren’t waiting for further recommendations from the WHO. Drafted in Italy in 2006 at a workshop organized by the new International Commission on Electromagnetic Safety, the resolution represents an emerging movement among scientists advocating that practicing precaution makes sense-especially in the absence of certainty.
“[We] believe that there is strong evidence of health risks associated with exposure to electric and magnetic fields, and electromagnetic radiation,” says Martin Blank, associate professor of physiology and cellular biophysics at Columbia University. “The great increase in EMF exposure in our environment may be contributing to the growing health problems we see in society,” says Blank, who has noted significant changes in cells due to low levels of EMF exposure. “The public should be made aware of the biological effects of EMFs and should start taking action to protect themselves.”
In addition to calling for independent funding and research monitoring, the resolution urges governments to develop precautionary guidelines now to protect public health. Specific recommendations include promoting alternatives to wireless technologies, requiring manufacturers to provide hands-free kits with all cellphones and cordless phones, limiting cellphone use by young children and designating wireless-free zones in cities and public buildings.

But we don’t have to wait on governments to protect us. We can take plenty of steps now to minimize our exposure to EMFs and RF radiation (see sidebars). At the same time, we can begin to ask ourselves as individuals and societies whether new technological innovations truly make life better in meaningful ways.
Thoughtful choices like these can help us find our way through the electronic smog to a future in which technology serves us well without compromising our health. And public concern is a powerful force for change. “I’m actually quite hopeful,” says Magda Havas of Trent University. “We’ve seen incredible strides in cleaning up asbestos, DDT, acid rain, PCBs, tobacco smoke and lead, so I’m convinced we’re ultimately going to have proper legislation that will limit where cellphone antennas can be placed and where you can use your cellphone and we’ll have wireless-free zones. I’m just hoping it will be a matter of a few years rather than decades. How quickly it happens will depend on how informed and wise a population we are and how much we care about health.”

Reducing radiation at home
The typical home with an Internet connection has nearly 11 electronic gadgets, according to a worldwide study published in 2006. At the same time, the average modern home contains about 30 appliances and electrical tools. Top it off with RF radiation from cordless phones and wireless routers, and it becomes clear that we’re bombarded with electromagnetic radiation every waking-and sleeping-moment. What can we do in our houses to protect ourselves?
• Computers - Because so little is known about the possible health effects of low-level RF radiation from wireless technologies, EMF expert Cindy Sage advises staying wired. She says the best option is CAT-5 cable, which allows high-speed Internet access. (Satellite receiver dishes for TV and Internet access are fine, by the way, because they only receive signals and therefore do not emit RF radiation. Satellite Internet sends outgoing information through a phone line.)
• Kitchen - Keep microwave ovens up on a shelf at one end of the kitchen and not on a work surface. And avoid induction cooktops. While energy-efficient, they emit high levels of EMFs.
• Bedroom - Don’t keep electric or digital alarm clocks or cordless phones on your nightstand. Skip electric blankets and “unplug” your bedroom as much as possible.
• Phones - Don’t use a cordless phone, which emits RF radiation similar to cellphones, when you can use an old-fashioned corded one. To keep your children off cordless phones and mobiles at home, give them a corded phone for their bedrooms. It’s fine to keep a cordless to use when you’re in the yard or garden, but come in the house to use a corded phone for longer conversations. Avoid DECT [digital enhanced cordless telecommunications] phones, which are often the strongest source of RF radiation at home. Unlike other cordless phones, DECTs are emitting RF radiation all the time, not just while the phone is in use.

Talk safely
And other simple ways to reduce your exposure to radiation
• Limit the length and number of cellphone calls. Use a land line whenever possible.
• Use an air-tube headset if you can’t avoid long hours on a cellphone, advises Alasdair Philips of Powerwatch, a British group that has been monitoring EMF issues for almost two decades With non-metal earpieces like those of a doctor’s stethoscope, it keeps RF radiation away from your head and ears.

• Keep your cellphone in a purse or briefcase, rather than clipped to your belt. Even on standby, cellphones emit radiation, usually out of the back of the phone, which can be absorbed by the liver and kidneys.
• Have the cellphone antenna hook-up installed outside your car.
• Be skeptical of shielding devices for handsets. They can block the signal and make the phone work harder, potentially emitting more RF radiation.
• Hang up and drive. Although not linked with radiation issues, talking and driving can be more dangerous than drinking and driving, according to a recent study by researchers at the University of Utah.
• When buying a new cellphone, choose one with the lowest possible SAR (specific absorption rate) value. For ratings, go to www.sarvalues.com.

Protect yourself
A wide range of Internet products claim to offer protection against the damaging effects of cellphone radiation. However no proof substantiates most of these claims. More to the point: Some protective measures have the opposite effect. For example, they can block the signal, which means the phone has to work harder, emitting more radiation. The authoritative British medical newsletter What Doctors Don’t Tell You reports on two of the more promising devices for protecting us from radiation and EMFs:

Q-Link
Though the Q-Link doesn’t eliminate radiation, many believe the pendant balances “subtle energies in the body” which affect our health. When the pendant is worn on a nylon cord hanging over the chest above the heart, the manufacturer Clarus claims it strengthens our resilience to stress and enhances our mental performance, boosting our overall capacity to function in EMF-saturated environments.
Several studies have been conducted on the effects of the Q-Link. Clarus says some users report that it helps relieve discomfort, improve sleep, increase energy and instill a greater ability to cope, both mentally and physically. Others report increased clarity and focus.
The problem is that the studies were performed on a very small scale and have not been published in recognized medical journals. The issue apparently remains too controversial. Nevertheless, the results-which include research conducted at Stanford University-are intriguing. Tests in humans showed that after wearing the Q-Link pendant for 72 hours, the negative effects of EMF radiation from a range of sources (including mobile phones, computers and power lines) on brainwave patterns were reduced. In a control group studied, however, the effects of the radiation remained in the blood.

More information:www.qlinkworld.co.uk and www.q-linkproducts.com

Tecno AO
This invention attaches to the radiation source-cellphone, video screen or cordless phone. According to the distributor, the Tecno AO emits a healing frequency that helps stabilize the body’s electromagnetic structures and enables them to better resist disturbance from random radiation.
Again, the scientific proof of the effectiveness of the Tecno AO is not yet completely convincing. One study into the effect of electromagnetic radiation on hatching eggs published in a medical journal revealed that 50 percent fewer eggs died when protected by the Tecno AO. Nonetheless, limited research, tests and descriptions of experiments show improvement in hormonal and immunological responses. These results indicate that the Tecno AO’s effect is more than just anecdotal.

More information: www.tecnoao.uk

Children and cellphones
In 2004, the Health Council of the Netherlands said it “sees no reason to recommend limiting the use of mobile phones by children.” The U.K. International Expert Group on Mobile Phones advised the opposite. The reality, says the Medical University of Vienna’s Dr. Michael Kundi, is that there’s very little research on children and cellphones. “There are no studies in children and few in young animals,” Kundi says. “We don’t know how the developing organism might react to this exposure, so if there are theoretical possibilities that it might cause harm and if there is no evidence showing that this is unfounded, then we should take precaution.”
Kundi also points out that children have thinner skulls than adults do and children’s skulls still contain bone marrow, which produces stem cells, blood cells and lymphocytes. And, he adds, the properties of brain tissue in children are different from adults because their brains are still developing. “This is known to every physician, but some still don’t think there are issues with children and mobile phones,” Kundi says. “I’m not so sure.”
How do you apply precaution in the real world with real kids? Environmental consultant Cindy Sage advises that children should not use cellphones, period. Yet, the phones are deeply embedded in our culture. Alasdair Philips of Powerwatch, a UK group monitoring radiation issues offers the same advice for young children, but it gets tricky when kids reach their teens. If you must buy a cellphone for your teenager, Philips advises teaching them to use it responsibly. “We need to tell children that there are significant health issues involved with a mobile and to treat it carefully.

A towering problem
Some communities in Europe are challenging the construction of cellphone towers or mobile masts (it’s not the structures themselves that are a problem, but the base-station antennas mounted on them, which emit RF radiation). For example, a group of German physicians has called upon the prime minister of Bavaria to stop additional masts and take other protective measures after documenting high rates of headache, fatigue, concentration problems and other symptoms among some patients who live near mobile masts.
Residents of Warwickshire, England, took matters into their own hands. They tore down a mobile-phone mast after 34 of 50 people living within 500 metres of it developed medical problems, including seven cases of cancer.
In the U.S., the federal Telecommunications Act of 1996 essentially prevents individuals and communities from expressing concerns about the siting of base stations near schools, neighbourhoods and other sensitive areas. But the national EMR Policy Institute in Marshfield, Vermont, pushes federal agencies and Congress to address public-health questions.
At the same time, some communities and states are calling for safer policies and effective action. For instance, the Los Angeles Unified School District has banned all new cell sites on its school property. The Connecticut Parent Teacher Association passed a voluntary resolution to keep cell towers and high-tension power lines at least 1,500 feet from schools. Connecticut is also the first state to require new high-tension power corridors in suburban areas to be buried underground. In addition, some towns around the country have successfully fought the construction of cell towers in sensitive areas.
Such local initiatives may be the first stirrings in a global groundswell to protect the public from the potential dangers of electronic smog. Though the challenges are significant, we can find ways to reduce exposure without forgoing the technology, such as siting cell towers and power lines a safe distance from sensitive areas.

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