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Post by Watchman on Aug 30, 2007 10:39:46 GMT -5
By Nic Fleming, Science Correspondent
Fresh fears over the health hazards linked to using mobile phones have been raised after scientists found that handset radiation could trigger cell division.
A study found that exposure to mobile phone signals for just five minutes stimulated human cells to split in two - a process that occurs naturally when tissue grows or rejuvenates, but that is also central to the development of cancer.
Previous research on the safety of mobile use has led to conflicting conclusions, with some suggesting links with tumours in the nervous system and others finding no risks.
The six-year Mobile Telecommunications and Health Research Programme, which provided £8.4 million of Government and industry funding for 25 studies, is expected to present its final report next month.
Official guidance that mobile phones were safe was based on the mainstream scientific assumption that electromagnetic radiation from such devices could damage cells and tissue only by heating them.
But the new research, reported in this week's New Scientist, supports the position of those researchers who argue that handsets can trigger potentially harmful changes to cells irrespective of temperature changes.
Prof Rony Seger, a cancer researcher at the Weizmann Institute of Science in Rehovot, Israel, and colleagues exposed rat and human cells to electromagnetic radiation at a similar frequency to that emitted by mobiles but at only about one tenth of the power.
After just five minutes the researchers identified the production of extracellular signal-regulated kinases (ERK1/2) - natural chemicals that stimulate cell division and growth.
Cancers develop when the body is unable to prevent excessive growth and division of cells in the wrong place.
Prof Seger said yesterday: "The real significance of our findings is that cells are not inert to non-thermal mobile phone radiation.
"We used radiation power levels that were around one tenth of those produced by a normal mobile. The changes we observed were clearly not caused by heating."
The UK has adopted international safety standards for electromagnetic radiation. These state that the amount of energy absorbed from an electric field or radio wave cannot exceed two watts per kilogram (W/kg) when averaged over 10 grams of tissue. Almost all mobile phones emit less that than one W/kg.
Graham Philips, of Powerwatch, a lobby group that campaigns on mobile phones, masts and powerlines, said: "Current safety guidelines assume health effects from mobiles can occur only when significant heating of body tissue occurs.
"This study shows biological changes in response to low-level mobile phone radiation - something that could have implications for health. Further research is required. However, guidance based purely on thermal effects is clearly out of date."
Other scientists pointed out that cell division occurred naturally as tissue grew or rejuvenated within the body, and that the preliminary study did not prove any health effects.
Simon Cook, a biochemist at the Babraham Institute near Cambridge, said: "The reason people are intrigued is that this pathway is frequently activated in cancer.
"The research is certainly interesting. However, they saw a very transient activation of this pathway, which we know is not sufficient to promote cell division.
"In cancer you see a much stronger, persistent and sustained activation and even this is just one of many changes required for cancer development."
Simon Arthur, from the University of Dundee, said: "The ERK1/2 pathway can be turned on by a huge variety of different things such as natural compounds produced by the body that regulate cell growth, and various forms of environmental and chemical stress.
"The research shows the effect on cells in culture in tightly-controlled laboratory conditions. In a living person there are lots of different processes occurring at the same time, so we do not know whether the signal from radio waves would produce a similar measureable effect."
The health debate
• May 2000: Parents left confused after an official report, chaired by Sir William Stewart, then chairman of the National Radiological Protection Board (NRPB), concluded that there were no proven health risks associated with mobile phones but that children should minimise their use as a precaution.
• Feb 2001: The Mobile Telecommunications and Health Research Programme (MTHR) set up to encourage further research into potential health hazards of handsets and masts.
• May 2001: Research in America suggested children's brains absorbed 50-70 per cent more radiation from handsets than adults because their skulls were smaller.
• Oct 2004: Swedish research concluded that those who used mobiles for 10 years were almost twice as likely to develop an acoustic neuroma - a tumour on a nerve connecting the ear to the brain.
• Jan 2005: Chairman of the Health Protection Agency advised parents not to allow children under nine to use mobiles because of potential but unproven risks.
• Dec 2006: A Danish study of people with brain tumours concluded there were no increased risks for heavy users.
• Jan 2007: A study in Finland of people with nervous system tumours called gliomas found no link with mobile use until it separated out long-term, regular users. It was concluded that they were 39 per cent more likely to get a glioma on the side of their head where they held their handset.
• Sept 2007: MTHR expected to present final report, including results of several unpublished studies. Prof Lawrie Challis, the chairman, expected to say there are no proven risks from short-term use, but to announce large-scale monitoring of health of handset users over 10 years.
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Post by Watchman on Sept 14, 2007 10:42:06 GMT -5
Mobile phones 'could cause brain tumours in long-term users' By JENNY HOPE -
Britain's biggest-ever study into mobile phone safety has warned that a long-term cancer risk cannot be ruled out.
Scientists say possible dangers to children are also unknown - despite the millions of pounds spent during six years of research.
As a result, investigators say they cannot update "precautionary" advice issued in 2005. That warned parents to limit children's use of mobiles and said those under eight should not use them at all.
The results from the Mobile Telecommunications and Health Research programme show no shortterm harm to brain and cells among adults from mobile phone signals or base stations, or from signals used by the emergency services.
But the scientists found a "very slight hint" of increased cases of some type of brain tumours among people who had been using mobiles for more than 10 years.
The data was "at the borderline of statistical significance" but should be investigated further, they said.
Little research was commissioned on children, largely because the programme prioritised adult research for ethical reasons and on the basis that it would produce information relevant to the youngsters.
The researchers called the results "reassuring", but stressed that further studies would be needed for the foreseeable future as mobile phone use continues to grow.
MTHR chairman Professor Lawrie Challis admitted that only a small proportion of the research had included adults using mobile phones for longer than a decade, usually the time needed for cancer symptoms to appear.
He said: "We cannot rule out the possibility at this stage that cancer could appear in a few years' time.
"There is no way we can do that, both because the epidemiological evidence we have is not strong enough to rule it out and because most cancers cannot be detected until 10 years after whatever caused them.
"With smoking there was no link of any lung cancer until after 10 years."
Professor Challis said two other studies had failed to find any adverse effects of mobile use on children.
But he accepted they reacted differently from adults to a number of other environmental agents such as lead and ionising radiation. Further research in the pipeline would look specifically at children.
In the meantime, there was nothing in the report that would change advice to parents about minimising their children's use of mobile phones, he said.
The MTHR programme was set up in 2001, with joint funding from Government and industry totalling £8.8million. Professor Challis stressed that it was run by independent experts so the "public can believe the results".
There are now 70 million mobile phone handsets in the UK, and around 50,000 masts.
Both emit radio signals and electromagnetic fields that can penetrate the brain, and campaigners fear this could seriously damage health.
Roger Coghill, of Coghill Research Laboratories in South Wales, which specialises in the effects of electromagnetic radiation, said the new report made "selective" choices for research which ignored growing evidence about brain effects.
He said "Normal use of a mobile phone for a couple of minutes may not cause any health effects, but what about calls of 20 minutes? Tradesman are among those making heavy use of their phones.
"There are many omissions in this report, not least important work on children, and there are biological reasons why we should have concerns about children and old people."
Yasmin Skelt, of the campaigning group Mast Sanity, which campaigns against base stations, said: "Mast Sanity believes that pulsed microwave radiation at current exposure levels represents a risk to health and that the MTHR programme doesn't go far enough and has ignored many independent studies showing the risk.
"They have only reviewed their own small sample of studies and ignored the thousands of existing studies showing a risk."
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Post by Watchman on Mar 31, 2008 12:11:06 GMT -5
Mobile phones 'more dangerous than smoking'
Brain expert warns of huge rise in tumours and calls on industry to take immediate steps to reduce radiation
By Geoffrey Lean Sunday, 30 March 2008
Mobile phones could kill far more people than smoking or asbestos, a study by an award-winning cancer expert has concluded. He says people should avoid using them wherever possible and that governments and the mobile phone industry must take "immediate steps" to reduce exposure to their radiation.
The study, by Dr Vini Khurana, is the most devastating indictment yet published of the health risks.
It draws on growing evidence – exclusively reported in the IoS in October – that using handsets for 10 years or more can double the risk of brain cancer. Cancers take at least a decade to develop, invalidating official safety assurances based on earlier studies which included few, if any, people who had used the phones for that long.
Earlier this year, the French government warned against the use of mobile phones, especially by children. Germany also advises its people to minimise handset use, and the European Environment Agency has called for exposures to be reduced.
Professor Khurana – a top neurosurgeon who has received 14 awards over the past 16 years, has published more than three dozen scientific papers – reviewed more than 100 studies on the effects of mobile phones. He has put the results on a brain surgery website, and a paper based on the research is currently being peer-reviewed for publication in a scientific journal.
He admits that mobiles can save lives in emergencies, but concludes that "there is a significant and increasing body of evidence for a link between mobile phone usage and certain brain tumours". He believes this will be "definitively proven" in the next decade.
Noting that malignant brain tumours represent "a life-ending diagnosis", he adds: "We are currently experiencing a reactively unchecked and dangerous situation." He fears that "unless the industry and governments take immediate and decisive steps", the incidence of malignant brain tumours and associated death rate will be observed to rise globally within a decade from now, by which time it may be far too late to intervene medically.
"It is anticipated that this danger has far broader public health ramifications than asbestos and smoking," says Professor Khurana, who told the IoS his assessment is partly based on the fact that three billion people now use the phones worldwide, three times as many as smoke. Smoking kills some five million worldwide each year, and exposure to asbestos is responsible for as many deaths in Britain as road accidents.
Late last week, the Mobile Operators Association dismissed Khurana's study as "a selective discussion of scientific literature by one individual". It believes he "does not present a balanced analysis" of the published science, and "reaches opposite conclusions to the WHO and more than 30 other independent expert scientific reviews".
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Post by Watchman on May 22, 2008 15:05:38 GMT -5
Cell Phones Increase the Risk of Two Types of Brain Tumor According to Study
By Cancer Monthly on December 10, 2007 9:17 AM |
Using mobile phones for more than 10 years gives a consistent pattern of increased risk for at least two different types of brain tumors. This was the conclusion of a summary that reviewed sixteen other research studies from seven countries – USA, Finland, Sweden, Denmark, United Kingdom, Germany, and Japan.(1)
Cell Phones Are Like Radios
Cell phones are more like radios than traditional telephones in your home. They emit low levels of radiofrequency energy (RF) in the microwave range while being used. They also emit very low levels of RF when in the stand-by mode. Using a cell phone can place the radiation antenna close to the user’s brain and this can lead to the absorption of comparatively large amounts of electromagnetic energy.
There has been an on-going debate about the safety of cell phones for many years. While, not surprisingly, the cell phone industry and various health authorities have assured users that the technology is safe, recent research has suggested otherwise.
Researchers at the Department of Oncology, University Hospital in Sweden reviewed sixteen published studies that looked at cell phone use and the rate of brain cancers. They concluded that:
“For both acoustic neuroma and glioma (two types of brain cancer), overall risk was increased in the whole group, but significantly increased for ipsilateral exposure (tumor on the same side of the brain as cell phone exposure)…These results are certainly of biological relevance, as the highest risk was found for tumors in the most exposed area of the brain, using a latency period that is relevant in carcinogenesis.”
Increased Risk of Acoustic Neuromas
Acoustic neuromas, also called schwannomas, are a non-cancerous tumor that develops on the nerve that connects the ear to the brain. The tumor usually grows slowly. As it grows, it presses against the nerves responsible for hearing and balance. Radiosurgery is usually the standard treatment.
Signs and symptoms of acoustic neuromas may include hearing loss, usually gradual — although in some cases sudden — and occurring on only one side or more pronounced on one side, ringing (tinnitus) in the affected ear, dizziness (vertigo), loss of balance, facial numbness and tingling. The tumor also may press on the brainstem and in rare cases, it may grow large enough to compress the brainstem and be life-threatening.
After reviewing the previous studies that looked at cell phone usage and neuromas, the authors found “an association with acoustic neuroma…in four studies in the group with at least 10 years use of a mobile phone.”
Their discussion of this issue included the following observations:
• Acoustic neuroma might be a “signal” tumor type for increased brain tumor risk from microwave exposure, as it is located in an anatomical area that receives high exposure during calls with cellular or cordless phones.
• Three studies did not have follow-up of at least 10 years, but two of them showed a somewhat increased risk for shorter latency periods.
• Three of the four studies with data on over ten years use showed a statistically significantly increased risk overall or for ipsilateral exposure to microwaves. (In this context, ipsilateral exposure means the tumor is on the same side of the brain as cell phone exposure).
• In one study, no association was found but the result was based on only two cases.
• The tumors were significantly larger among mobile phone users.
Increased Risk of Gliomas
The researchers also found that the risk of glioma increased significantly per year of use.
A glioma is a type of primary central nervous system (CNS) tumor that arises from glial cells. The most common site of involvement is the brain, but they can also affect the spinal cord or any other part of the CNS, such as the optic nerves. Gliomas can be either benign (slow growing) or malignant (fast growing). Types of gliomas include:
• astrocytomas • ependymomas • oligodendrogliomas • mixed gliomas
Treatment for a glioma — and survival odds — depends on tumor type, size and location, and the patient’s age and overall health. Often, treatment is a combined approach, using surgery, radiation therapy, and chemotherapy. High grade gliomas like anaplastic astrocytomas and glioblastoma multiforme can be particularly difficult to treat.
Symptoms of gliomas depend on which part of the central nervous system is affected. A brain glioma can cause headaches, nausea and vomiting, seizures, and cranial nerve disorders as a result of increased intracranial pressure. A glioma of the optic nerve can cause visual loss. Spinal cord gliomas can cause pain, weakness or numbness in the extremities.
In respect to gliomas and cell phones, the researchers concluded “that using a ten year or more latency period gives a consistent pattern of association between use of mobile phones and malignant brain tumors, especially high-grade glioma.” The researchers also found an increased overall risk more pronounced for ipsilateral use of the cell phone (tumor on the same side of the brain as cell phone exposure).
What to Do?
This study did not say that cell phone use leads to brain tumors, only that long-term use may increase one’s statistical risk of certain brain tumors. In addition, it should be noted, that other studies have concluded that there is no connection between cell phones and increased risk of cancer. This issue is far from resolved. But for those heavy cell-phone users who want to err on the side of caution, it may be wise to use one of the various non-RF devices (such as headphones) that can place some distance between a cell phone and the user’s brain.
Endnotes
(1) Hardell L, et al., Long-term use of cellular phones and brain tumors: increased risk associated with use for > or =10 years. Occup Environ Med. 2007 Sep;64(9):626-32.
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