It is unfortunate however, that apparently no current Australian breast cancer research is examining the growing evidence that low level exposures to 50-60 hertz electromagnetic fields (EMF) may block melatonin's ability to suppress breast cancer cells and reduce the pineal gland's nocturnal production of melatonin, thereby increasing susceptibility to breast cancer. This evidence is supported by both human and laboratory studies, some of which are summarised in this paper. Many of these studies are still awaiting the peer review process and as such do not yet constitute part of the body of substantiated scientific evidence, often referred to by national and international expert regulatory groups. The peer review process can take years to complete.
Considering the prevalence of breast cancer in western society and the extensive body of evidence pointing to a connection with EMF exposure, it is the position of this paper that with breast cancer patients, avoiding excessive EMF exposure should be part of the treatment, under the Precautionary Principal, which in this case could be defined as:
The precautionary principal should guide decision-makers when confronted by potential threats to human health. The lack of full scientific certainty should not be used as a reason for postponing measures to prevent exposure to these potential threats. If measures generally reducing exposure can be taken at reasonable expense and with reasonable consequences in all other respects, an effort should be made to reduce exposures to a level below that level which evidence indicates may be harmful to health.
Both human and animal circadian rhythms are driven by the day/night cycle and are synchronized with natural geomagnetic electromagnetic fields. The major control gland over this natural cycle is the pineal gland and its secretion of the neurohormone melatonin. During the day light falling on the eye's retina produces signals which are biochemically amplified to stimulate the pineal gland to reduce its melatonin output. At night the absence of light with sleep stimulates the pineal gland to produce melatonin. The circadian production of melatonin is thought to control important processes in the eyes, including restoration of rods (for night vision) at the end of the night, and renewal of cones (for colour vision) at the end of the day. One theory on how man made EMF's may affect the pineal gland is that the pineal gland may 'sense' EMF's as light and therefore reduce melatonin production. A possible cause for this effect is from insoluble granular material contained within the pineal gland.
Research by Dr. Sidney Lang, an expert on piezoelectricity, which is the production of electric fields by pressure on crystalline structures, has shown that the pineal gland has piezoelectrical activity. Dr Lang hypothesizes that this activity is a function of this granular material and if so it may be responding to narrow wave lenghts. (1)
Once melatonin is produced, its ability to pass through the cell membrane allows it to pass directly into the blood stream. Once in the blood melatonin has access to every cell in the body where it passes through the cell membrane to the cell nucleus, which has receptors for it. A few cell membranes also have receptors for melatonin, which may control the 24 hour circadian rhythm of the endocrine system.
In the cell nucleus melatonin plays a role in regulating gene expression. The ability of melatonin to enter all cells is also essential for one of the other important functions of melatonin, which is to act as a scavenger of highly toxic oxygen-based free radicals. The production of these free radicals is a consequence of the utilization of oxygen by all organisms. About 1 - 2% of inspired oxygen ends up as toxic free radicals which can damage macromolecules such as DNA, proteins and lipids. This damage is referred to as oxidative stress.
Because of its ability to eliminate free radicals, melatonin is probably the most efficient natural cell protection and oncostatic agent in our bodies. At night, melatonin production floods our bodies, eliminating the build up of free radicals that are being produced, allowing the DNA synthesis and cell division to occur with a far lower chance of damage and hence producing more healthy cells. Melatonin also dampens the release of estrogen, prolonged exposure to which may increase the risk of breast cancer. (2)
Tamoxifen, which is the most widely used therapy for treatment of breast cancer, has proven effective in treating breast cancer in its early stages, is also used by over one million women throughout the world who have had breast cancer, to prevent its recurrence.
Electromagnetic Fields (EMF)
In 1987 Stephens et al. in the paper, "Electric power use and breast cancer; a hypothesis", suggested that electromagnetic fields (EMF's) reduce melatonin production by the pineal gland and that melatonin suppresses the development of breast cancer. (3)
Other researchers have also hypothesized that the possible suppression of melatonin by electromagnetic fields may provide a single mechanism for explaining how number of different types of cancer could be promoted by EMF's, however this suggestion has been hotly debated due to the previous failure to replicate several key studies. Replication is a key step in the scientific method for it takes an unproven hypothesis to a significant conclusion which can be acted upon.
Research in 1993 by Liburdy, et al. found that melatonin reduces the growth rate of human breast cancer cells (MCF-7) in culture, but that a 12mG 60 Hz magnetic field can block the ability of melatonin to inhibit breast cancer cell growth. (4)
This study has now been replicated four times. It is this replication and the three human exposure studies also mentioned herein, that have significant implications for the successful treatment of breast cancer and calls for immediate action from researchers and oncologists alike. The failure to do so, under the excuse of "more research needs to be done" is not acting in the best interests of breast cancer patients, to say the least.
In June 1996 at the 18th. Annual Meeting of the Bioelectromagnetics Society (BEMS) the following three replicated studies were presented which have important implications in the treatment of breast cancer, and by implication other cancer types as well.
1) ELF INHIBITION OF MELATONIN AND TAMOXIFEN ACTION ON MCF-7 CELL PROLIFERATION; FIELD PARAMETERS. J.D. Harland and R.P. Liburdy. Lawrence Berkeley National Laboratory, University of California, Berkeley, California, USA.
This study was designed to define the parameters by which a 12 milliGauss (mG) 60 Hz magnetic field can block the inhibitory action of melatonin and Tamoxifen, a widely used drug treatment for breast cancer. They found that a 12 mG field can significantly reduce the growth inhibitory action of melatonin and Tamoxifen on human breast cancer cells (MCF-7) in culture.
"Preliminary experiments suggest that at least three days exposure at 12mG is necessary to block the cytostatic action of Tamoxifen (from 27% growth inhibition, p<0.0001; to 5% growth inhibition, p>0.5 ) indicating that prolonged 12mG exposure may be required. This appears to be consistent with a "slow" interaction mechanism. This result also raises the possibility of field effects that may be cell cycle dependent, since measurable effects appear to be delayed or reversible until cell division begins. In addition, all field magnitudes of 12 mG or higher that have been tested thus far (12mG, 20mG, 1Gauss) have been effective at blocking melatonin." (5)
A lower field of 2mG did not have any significant effect, suggesting a threshold might exist between 2 and 12 mG.
2) INDEPENDENT REPLICATION OF THE 12-MG. MAGNETIC FIELD EFFECT ON MELATONIN AND MCF-7 CELLS IN VITRO. C.F.Blackman, S.G. Benane, D.E. House and J.P. Blanchard. National Health & Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, USA.
This study was specifically designed to attempt to replicate the previous study, with the cooperation of the originating laboratory. The results independently confirmed the previous study's findings. As follows:
1) Melatonin can inhibit the growth of human breast cancer cells MCF-7 in culture.
2) A 12 mG 60 Hz magnetic field can completely block melatonin's oncostatic action.
The authors of this study believe these results are particularly significant because these findings represent the first replication of a key magnetic bioeffect, and that these two studies represents a foundation for theorists to generate "testable" hypotheses for biological mechanisms of interaction. (6)
3) INHIBITION OF MELATONIN'S ACTION OF MCF-7 CELL PROLIFERATION BY MAGNETIC FIELDS ASSOCIATED WITH VIDEO DISPLAY TERMINALS: A PRELIMINARY STUDY. S.M.J. Afzal and R.P. Liburdy. Lawrence Berkeley National Laboratory, University of California, USA.
This study was undertaken to test the hypothesis that ELF and VLF magnetic fields associated with Video Display Terminals (VDT's) influence human breast cancer cell growth in vitro by altering melatonin's natural oncostatic activity. This hypothesis was based on the findings of the two previously mentioned studies.
The conclusions of this study appear to suggest that 12 mG VDT magnetic fields also inhibit the oncostatic action of melatonin in vitro and that the magnetic field component was the operative factor in the 12 mG 60 Hz exposures. Preliminary data from two seperate experiments indicated significant growth inhibition (33% and 22%) on day 6 in the 2 mG magnetic field conditions.(7)
A fourth replication study of a 12 mG effect on MCF-7 breast cancer cells was presented at San Antonio Texas in Nov.1996 by Dr Richard Luben, as follows:
4) REPLICATION OF 12 mG EMF EFFECTS ON MELATONIN RESPONSES OF MCF-7 BREAST CANCER CELLS IN VITRO . R.A. Luben, S.Saraiya and A.P. Morgan. Division of Biomedical Sciences, University of California, Riverside, California 92521, USA.
The objective of this study was to replicate, with the cooperation of the originating laboratories, the studies conducted by Liburdy and Blackman.
They "found that exposure of breast cancer cells to 12 mG 60 Hz EMF induced a reproductable net increase (mean +28%, p<0.001) in the growth rate of MCF-7 cells treated with a physiological dose of melatonin. This constitutes a replication of the observations reported previously by Liburdy and Blackman, in that EMF produced a blocking of the anti-cell-growth effects of melatonin. There are some variations between our findings and theirs: . . ."Nevertheless, the net differences between (melatonin+EMF)and (melatonin-EMF) groups is both qualitatively and quantitively consistent in all the studies. . ." (8)
It does not necessarily mean that these in vitro study conclusions can be directly applied to breast cancer patients. However it is important to note that some recent human exposure studies also indicate a melatonim/EMF effect, and that levels of 12 mG or higher can be routinely encountered in daily life, for example, electric blankets can give emissions in excess of 12 mG. Sleeping with an electric blanket on is a special concern, as it is at night that the pineal gland, located near the centre of the brain, produces melatonin. In the study by Liburdy and Harland, indications were that a prolonged exposure may be required, which is a further possible implication of electric blanket use while sleeping.
In a study by Yaofei Liu and Dr. Indra Chatterjee at the University of Nevada they found that with electric blankets, "The average current density (induced in the body) in the head is higher than the torso because of the smaller cross section of the head."(9)
Studies by B. Wilson et al at Battelle Pacific Northwest Laboratory have shown that melatonin synthesis is altered by exposure of animals to ELF electromagnetic fields, and he and others have proposed that disruption of the normal daily cycles of melatonin synthesis could be a risk factor for human breast cancer. (10) Battelle is currently running a replication study on the above mentioned three studies.
In a soon to be published follow up study by Dr. Henry Lai and Dr. Narendra Singh, who earlier found single and double strand DNA breaks in rats exposed to low level radiofrequency radiation (RFR) after a single two hour exposure, the treatment of either melatonin or a free radical scavenger (PBN) to the exposed rats immediately before and after RFR exposure prevented the DNA damage. (11) This indicates the importance of melatonin in DNA repair mechanisms, and therefore in cancer suppression, but not that the RFR is effecting is the rats own pineal melatonin production. The current body of evidence examines Extremely Low Frequency (ELF) 50-60 Hz fields and its effects on melatonin. At this point in time evidence for a similar effect from RFR does not exist. (12)
In a study by Tan et al in 1993, rats were injected with a chemical carcinogen, Safrole which damages DNA by inducing the production of large numbers of free radicals. Rats injected with Safrole were found to have extensive DNA damage after 24 hours. When melatonin was also injected, the DNA damage was reduced by 99%. (13)
A preliminary study of 60 workers at a Finnish garment factory found "a highly significant effect"of EMF's in reducing nocturnal melatonin levels. Magnetic field measurements were taken for the two types of machines used in the factory and operators were assigned to high or low exposure groups, based on the type of machine they were using, with average exposures either above of below 10 milliGauss. Unexposed non industrial workers were used as controls.
The results of this study found strong effects of both magnetic field exposure and smoking on night time levels of melatonin. No difference was found in melatonin levels on week nights and Sunday nights, indicating "that the possible suppression caused by magnetic field exposure is chronic, with little recovery during the weekend." (14) - consistent with the effect of chronic electric field exposure in the rat experiments of Wilson et al. (1986) (15)
In a study of 192 electric utility workers, Drs. John Reif and James Burch, from the Colorado State University, found that some EMF exposures are associated with lower levels of melatonin. They found a significant association between magnetic field exposures and lower daytime melatonin levels on the second and third of three days of measurement. The lack of an effect on the first day (following a weekend or equivalent) may indicate a cumulative effect of exposure. Some studies have suggested that EMF effects on melatonin may depend on whether the field is continuous or intermittent. Reif and Burch found that magnetic fields in the home that were "temporally coherent"(less intermittent) had a very significant association with lower melatonin levels at night. They concluded that, "The intensity and temporal characteristics of magnetic fields appear to be involved in melatonin suppression." (16)
Office workers who used computer monitors (VDU's) had a significant reduction in circulating levels of melatonin over a course of the working day, according to a study by researchers Drs. Bengt Arnetz of the Karolinska Institute, and Mats Berg of the Karolinska Hospital in Stockholn Sweden. No such change was found during days at the office with no VDU use. According to the researchers; "This suggests that there is a direct impact from the electromagnetic environment of the VDU on levels of melatonin." Levels of a different hormone, adrenocorticotropic hormone (ACTH), went up during the working day and this showed a strong correlation with worker's subjective assessment of mental strain. Arnetz and Berg note that ACTH is "known as a classic stress hormone that reacts to mental strain." But in contrast, "occupational strain did not correlate with melatonin levels." (17)
This finding supports the Boston University breast cancer study, in which Patrica Coogan and co-workers found a 43% increase in breast cancer among women with a high potential for occupational exposures to magnetic fields, notably those working with main-frame computers. In an interview with Microwave News, Coogan said,"This study lends credence to the idea that EMF's might influence breast cancer." (18)
Not all human exposure studies found a melatonin reduction effect. A study by Dr. Charles Graham et al at the Midwest Research Laboratory in Kansas City, MO. conducted for the Electric Power Research Institute (EPRI), found that a continuous 60 Hz, 200 mG magnetic field applied to people while they slept had no effect on nocturnal melatonin levels.
In a similar study published in 1994, Graham found no overall effect for intermittent EMF exposures, however, date from that study showed that men with preexisting low levels of melatonin had even lower levels when exposed to EMF's, suggesting that a person's prior melatonin level may be an important factor. Later research by Graham failed to replicate this finding however.
Graham cautions against a conclusion that EMF's do not effect melatonin. He points out that all of the volunteers in his studies were "healthy young men", and that the types of EMF's with which people come in contact in an industrialised society are much more varied than those created in the carefully controlled MRI exposure facility. (19)
In relation to this, Dr John Reif of Colorado State University comments,"Most natural observations appear to find melatonin changes, while controlled lab studies tend not to. . . In a general way, I'm concerned that the controlled lab trials may not mimic exposures in the real world."(20)
The International Breast Cancer Intervention Study
This study, which has been running for five years now, is aimed at discovering if the drug Tamoxifen can help prevent the disease in those who have not yet developed it but are at increased risk.
Women from the UK, Europe, New Zealand and Australia are participating in the study, which is open to women aged between 35 and 70 who have a strong family history of breast cancer.
Those aged 45 to 70 must have had a close family member diagnosed with breast cancer at the age of 50 or under, or in both breasts at any age, or must have two close blood relatives who have had breast cancer at any age. Those aged 35 to 45 must have had a close family member diagnosed with breast cancer before 40 or at least two close blood relatives who have had breast cancer before 50.
Each participant is encouraged to continue with the study for 5 years. During that time they take one tablet, which is either Tamoxifen or a placebo, each day and receive a clinical assessment every six months and a mammogram each year. If Tamoxifen is proved effective it could ultimately be provided to women at increased risk.
Considering the above mentioned studies, especially the study by Liburdy and Harland, "ELF Inhibition of Melatonin and Tamoxifen Action On MCF-7 Cell Proliferation; Field Parameters", which found that a 12 mG magnetic field can significantly reduce the growth inhibitory action of melatonin and Tamoxifen, participants EMF exposures should be included in the International Breast Cancer Intervention Study as a possible confounding factor. If EMF exposures are a possible confounding factor, the statistical model for analysis of the study should take into account this possible factor. If not, the possible EMF factor may put enough statistical noise to the study that the conclusions may well be affected as the effectiveness of Tamoxifen may be reduced in those participants with relevant EMF exposures.
If environmental EMF's, and electric blanket use are a confounding factor, this should be possible to check by questioning the subjects on their habits, maybe even taking home and workplace EMF exposure readings. If some participants are found to be exposed to prolonged EMF exposures in the order of 2 to 12 milliGauss (there appears to be a dose-response relationship from 2 to 12 milliGauss) it may be necessary to advise them to avoid these exposures.
It may also be advisable to do actual measurements of melatonin levels in those subjects identified as being prone to breast cancer. Women with breast cancer have shown a lower nocturnal increase in melatonin levels than control women. (21)
In the September 1996 issue of Epidemiology, Susan Preston-Martin reviews much of the data on topic. She also calls for including melatonin levels in breast cancer risk assessment studies and for obtaining an ELF exposure history.
A possible avenue for research would be to determine if the use of melatonin would have a similar protective effect as Tamoxifen, as breast cancer patients may have a better prognosis if their melatonin levels are high.(22)
Also on the Liburdy and Harland study: what do Tamoxifen and melatonin have in common, and why is their effectiveness mitigated by exposure to EMF's?
Professor Russell Reiter who has been researching the effects of EMF's on melatonin production has done a review paper on this subject. This review paper was prompted by a number of epidemiological studies in which an increased incidence of cancer was reported in individuals living or working in an environment of higher than normal artificial electromagnetic fields. His paper extract concludes with the following observation:
"Reduction of melatonin at night, by any means, increases cell's vulnerability to alteration by carcinogenic agents. Thus, if in fact artificial electromagnetic field exposure increases the incidence of cancer in humans, a plausible mechanism could involve a reduction in melatonin which is a consequence of such exposures."
Dr. Reiter also notes:
" Epidemiologists should look for other possible changes, including psychological depression, fatigue, sleep inefficiency, chronic feelings of jet lag, endocrine disturbances and other symptoms; all these may result from a chronically low melatonin rhythm." (23)
As a result of his latest study Dr. Reiter now proposes that melatonin is "more rapidly taken up into tissues during the exposure." He noted that if EMF's result in higher levels of free radicals, then an antioxidant like melatonin "would disappear from the blood more quickly than is normal because it would be required for the scavenging of free radicals." (24)
If Reiter's hypothesis is correct, then prolonged exposures may tax the pineal gland's ability to maintain adequate levels of melatonin to cope with the extra stress created by EMF exposure, and also Tamoxifen's ability to inhibit the growth of breast cancer cells.
The ground-breaking research suggests that people living within 20m of high-voltage lines are three times as likely to suffer from asthma and twice as likely to have major depression. Researchers believe the danger levels drop rapidly beyond this area.
The major new study also indicates that these people have a higher incidence of diabetes and are twice as likely to suffer from immune-related illnesses such as allergies and dermatitis.
Auckland is most affected because of the city's population density but high-voltage lines stretch throughout the country.
Although less than 1 per cent of New Zealanders live near the lines, the research has implications for the vast number of people exposed to electromagnetic fields at work. For example, industrial sewing machine operators, welders and some supermarket check-out operators are subjected to prolonged magnetic field exposure. But, although the evidence linking electromagnetic fields to health problems mounts, scientists are yet to prove the link.
The research is expected to stimulate worldwide debate when it is presented to an international symposium on electricity and magnetism in Italy next month. The study will also be published in the official journal on biological effects of electromagnetic fields.
An Auckland University academic involved in the research, Professor Ivan Beale, said the negative health effects of living close to high-tension power lines were more widespread than previous studies had shown.
Some 570 people in South Auckland, West Auckland and the eastern suburbs took part in the three-year Study. The participants consented to detailed measurements of magnetic fields being taken in their homes, to releasing their medical records and giving blood samples.
The study into the effect the power lines had on the nervous and immune systems revealed that adverse health effects became apparent in homes with magnetic field readings as low 5 milligauss or mG. (The reading is obtained by measuring the density of the magnetic fieId with a hand-held device.) One home recorded a 190mG reading.
Professor Beale, of the university's psychology department, said the research findings added weight to other studies which suggested the internationally accepted electric field exposure limits should be lowered.
The National Radiation Laboritory recommends 1000mG as a safe level, based on the guidelines.
Houses close to high-voltage lines, which already sell more cheaply because of the lines, could be under further price pressure as the result of the research.
"Personally, I would not want to live underneath those power lines - I would want to move as soon as possible, not because I'm certain I would be affected adversely but I would not want to live with the doubts," Professor beale said.
While research continued, Professor Beale advised people adopt a cautionary approach by avoiding magnetic fields where possible.
He likened it to earlier this century when agents like tobacco and asbestos were suspected of causing harm - but it was many years before there was conclusive proof.
When presented to 'Science' magazine for publication the study was rejected on the grounds that publication "would cause a panic". Three other prominent magazines including 'Nature' also later rejected the report, suggesting that they would not handle such important conclusions without the research being further confirmed.
The study looked at 200 mice, half exposed and half not, to pulsed digital phone radiation. The work was conducted at the Royal Adelaide Hospital by Dr Michael Repacholi, Professor Tony Basten, Dr Alan Harris and statistician Val Gebski, and it revealed a highly-significant doubling of cancer rates in the exposed group.
The mice were subject to GSM-type pulsed microwaves at a power-density roughly equal to a cell-phone transmitting for two half-hour periods each day; this was pulsed transmission as from a handset, not the steady transmission of a cell-phone tower.
A significant increase in B-cell lymphomas was evident early in the experiment, but the incidence continued to rise over the 18 months. The implications of the B-cell (rather than the normal T-cell) lymphomas here, is that B-cell effects are implicated in roughly 85 percent of all cancers.
The experiment was conducted as a blind trial, using absolutely identical equipment and conditions for two groups of 100 mice. The only difference between handling the two groups was that the power to one antenna was never switched on. Over the 18 months, the exposed mice had 2.4-times the tumour rate of the unexposed - but this was later corrected downwards to a more confident 2-times claim to remove other possible influences.
According to Dr Alan Harris from the Walter and Eliza Institute in Melbourne: "This is important because at present, there was no convincing evidence that radio fields (in contrast to X- and Gamma-rays, ultraviolet and atomic radiation) can directly cause the changes in genes responsible for cancer development."
In fact, until late 1996, most governments and all cell-phone companies have been claiming that the safety of their product has been proved - and that the only possible biological effect of radio frequency transmission is localised body heating.
The conduct of this experiment actually raises questions more about the potential for cell-phone handset radiation to affect people nearby (passive exposures) than just the user him/herself. The experiment was conducted in the 'far field', at distances greater from the mice than the cell-phone is normally held from the head.
Near-field biological effects in EMF effects are thought to be sustantially different from far-field, although the biomedical implications are not clear. Also, in close proximity, most of the energy transfers from the handset to the head by induction rather than just radiation, and this can raise the energy transfer by a factor of four.
The study therefore under-rates the potential power effects on the handset user, while over-rating those for people nearby.
The Adelaide study has been held back from publication for over two years while the B-cell implications were checked at a laboratory in Maryland, USA. Under their contract with Telstra, those involved in the study were prohibited from discussing their findings until after publication.
Increased tumours began to be recorded after about 9 months. It is important to note that these were transgenic mice, specially bred to be susceptible to cancers of the immune system. However susceptible mice are commonly used in these studies as 'proxies', since cancer-causing effects are believed to be cumulative at the cell level.
The total exposure period is very much less than can be expected from human use over a lifetime, so while one of the scientists downplayed the importance, saying, "humans are not rodents" another pointed out that "DNA is DNA".
Every attempt appears to have been made to hose down the significance of this report, however the importance of the finding will not be lost on the international scientific community. This research now places Australia at the fore-front of EMF-health research, and it demands a series of follow-up studies to investigate dose-related responses and near-field effects.
An expensive video-conference is being mounted on Wednesday by Telstra in Adelaide to officially release the report, with Dr Michael Repacholi speaking from Geneva. He has been prominent crusader on the side of "cell-phones are safe" lobby for many years. However, none of the technical or medical press involved in this debate have been invited to Adelaide conference.
The official press release issued by the chairman of the scientific committee, Professor Tony Basten of Sydney University, also leads with gentle fire-extinguisher statement that "In our opinion the findings are valid for this genetically-engineered mouse model, but they must be put in context. Mice and humans absorb energy from these fields differently so we cannot conclude from this single study that humans have an increased risk of cancer from the use of digital mobile phones. More focussed research needs to be done to resolve that issue"
I couldn't agree more on the last point, but nothing done in the last few years with the exception of the Drs. Lai-Singh work in Seattle has more obviously established that cell-phone safety has not yet been proved. There has been evidence accumulating over many years that the long-term effects of radio-frequency exposures may have serious consequences for a small percent of the population, but this has been ignored by the industry and by governments.
The fact that Prof. Tony Basten concluded his release with the statement "For the time being, at least, I see no scientific reason to stop using my own mobile phone," is largely irrelevant. At his age and in his occupation, the potential dangers from increased phone use are probably minimal.
The question is, would he buy his teenage child one?
This report follows two other fierce brush-fire in the cell-phone industry. The first was generated last year when Dr Henry Lai and Dr Singh at Washington State University reported enormous increases in double-strand DNA breaks in rat-brain tissue following microwave exposures of only two hours. The industry largely ignored these findings claiming that the frequencies used were not identical to cell-phones.
In addition, the Wireless Technology Research (WTR) group in the USA, which is funded by the cell-phone industry has become embroiled in a number of scandals. The WTR was promoted to the public and to the US Government as being an 'independent' and 'arms-length' body controlling $25 million in research funding.
Recent leaked documents show that it has been under the direct control of the industry association, and it has long operated as a PR front. In the last four years it has spent $17 million "without wetting a test-tube, " according to Microwave News editor, Louis Slessin.
Following the tobacco industry's problems, the WTR scientists recently went on strike for nearly a year, refusing to perform their contracted research until adequately covered for indemnity against law suits by the cellular phone industry association. Last week, the WTR was finally paid US$938,000 to fund indeminity insurance coverage.
The US scientists' sensitivity to this issue follows the filing of thirty-eight cases which are now before the courts over past tobacco-safety studies. Both the tobacco company lawyers and the scientists they funded have been charged as co-conspirators with the Tobacco Institute and the cigarette companies in suppressing evidence and manipulating research results.
More information on Cell-phone Health Issues can be found at Stewart Fist's Electric Words -- Issues, Interests and Technology web site or check out his Home Page.
The results, published in the journal Neurology, indicate that people who are exposed to high EMF levels on the job--seamstresses in particular--have, on average, three to five times the normal risk of contracting the devastating disease of aging.
The results, from a study at Rancho Los Amigos Medical Center in Downey, follow on the heels of a September report from the Centers for Disease Control and Prevention indicating that a broad variety of neurodegenerative diseases, including Alzheimer's, are more common among workers exposed to EMF on the job.
"We're not talking about exposure in the home from [living near] high-power lines," said Dr. Eugene Sobel of USC, the primary author. "These [occupational exposures] are much higher exposures than are usually found in residences."
The greatest risk was for people who operate sewing machines. "Seamstresses are highly overrepresented among Alzheimer's cases, and their exposure is the highest for all occupations," Sobel said. The exposure is high because they work so close to the electrical motor in the machine.
Also at risk are carpenters and others who use electrically powered tools held close to the body, he said.
Many researchers are skeptical of the finding, however. "Our bottom line is that [the results] are really too preliminary to say anything," said Dr. Neil Buckholtz, director of Alzheimer's research at the National Institute on Aging, which sponsored the study. "It really needs to be reproduced by some other group before we can have a lot of confidence in it."
"There are all kinds of other things, such as chemicals, in the work environment that could account for the relationship," added Zavan Khachaturian, director of the Alzheimer Assn.'s Reagan Research Institute. "There is room [in the data] for all kinds of inadvertent biases."
In contrast, EMF expert Louis Slesin, editor of Microwave News, calls the results "very important. . . . The thing about Sobel's findings is that we now have four data sets, across different countries and different populations, with consistent results. . . . That points to the need to investigate this further."
Sobel, Zoreh Davanipour and their colleagues studied 326 Alzheimer's patients over the age of 65 who were hospitalized at Rancho Los Amigos and compared them to 152 non-Alzheimer's patients at the medical center.
They found, primarily through interviews with family members, that males with Alzheimer's were 4.9 times as likely to have had a high occupational exposure to EMF and females were 3.4 times as likely.
The results were similar to those in three earlier studies, involving a total of 386 Alzheimer's patients and 475 controls in Finland and the United States, in which Sobel and his colleagues had also found an average threefold increase in risk.
The potential risks of EMF exposure have been a source of controversy for 17 years, since Colorado researchers first linked high EMF exposure in children living near power lines to an increased incidence of leukemia. Subsequent studies also showed an increased risk of brain tumors and other types of cancer.
Those studies, however, have typically shown relative risks of 1.5 to 1.7 times for exposure to EMFs, much lower than the threefold or greater risk increase found by Sobel.
Much of the interest in EMFs has abated, furthermore, since the National Academy of Sciences issued a report in October indicating that there is no clear and convincing evidence of a link between residential EMFs and cancer.
But biochemist Richard A. Luben of UC Riverside, a member of the committee that prepared the report, noted Tuesday that the committee had not considered either industrial exposures or a potential link to Alzheimer's. There was not enough evidence about either topic for them to explore such links in detail, he said.
"If the data suggest that something is going on" in Alzheimer's, Luben said, "we have to look at it in greater detail, especially when we are dealing with a disease that so many people contract."
Alzheimer's disease afflicts as many as 4 million Americans, most over the age of 65. It is characterized by memory loss, disorientation, depression and deterioration of bodily functions. It is ultimately fatal, causing about 100,000 deaths each year.
Its cause is still unknown. Although researchers have linked at least two different susceptibility genes to the disease, it is clear that as-yet unknown environmental factors also play a major role.
In a second paper in Neurology, Sobel and Davanipour outlined a potential biological pathway by which EMF could theoretically exert its effects. The bottom line, based on other researchers' studies of brain cells grown in the laboratory, is that electric fields can disturb the normal concentrations of calcium ions within cells.
The increased concentration of calcium within the cells produced by EMFs, they speculate, triggers a well-known cascade of reactions that ultimately leads to the accumulation of damaging plaques and tangles in the brain.
The role of calcium in Alzheimer's was originally postulated by the Reagan Institute's Khachaturian, but he does not subscribe to the USC hypothesis. He believes that a calcium imbalance can be caused by biochemical reactions, "but we have never seen any relationship between that process and EMF. . . . To jump from cultured cells to humans is a very, very big jump."
The scientists, who have been examining the effects of radiation similar to that produced by mobile phones, explain their fears on BBC's Watchdog HealthCheck programme tonight.
Two of them say that they have completely stopped using mobile phones, while the other four say they use them "only when essential" because of the possible risks.
Dr Henry Lai and Dr N. P. Singh from the University of Washington in Seattle report on the damage caused to DNA in the brain cells of rats exposed to microwaves.
Their work suggests that "hot-spots" may develop inside the brain, causing damage which could lead to Alzheimer's or cancer.
Dr Peter French, an immunologist from New Zealand, tells the programme: "I have a mobile phone . . . but now I use it only when absolutely essential. I switch sides if the call goes on longer than a minute or two."
In recent experiments exposing cells derived from human tissue to mobile phone radiation he records changes in cell structure and growth rate which were likely to promote asthma.
Dr Bruce Hocking, a former medical director of the Australian state-owned telephone company Telstra, says he logged more than 40 cases of mobile phone users who complained of severe headaches and muscle pain in the neck and upper arm.