The evidence that wi-fi can adversely affect health is drawn from both epidemiological studies and studies of animals. Of the effects researchers have shown, the following are clearly extremely serious:
• behavioural and functional degradation ( 11.1 )
• brain damage and possible premature senility (11.2 )
• cancer induction ( 11.3 )
The evidence in each case relates to exposure levels equivalent to or below those of wi-fi.
The experts on the Health Protection Agency’s Electromagnetic Fields Discussion Group, referred to above, say that the most commonly reported adverse effects of microwave radiation are headaches, concentration difficulties, learning and memory problems, chronic fatigue, depression, and behavioural problems. They point out that these symptoms are present in many ADHD children (Attention Deficit and Hyperactive Disorder), and that there has been a four-fold rise in children diagnosed with ADHD since 1997, when the widespread use of mobile phones and masts began. They suggest that microwave exposure from these sources may be a factor in this rise. 54
One study of residents living near or under a phone mast showed that “the prevalence of neuropsychiatric complaints [such] as headache (23.5%), memory changes (28.2%), dizziness (18.8%), tremors (9.4%), depressive symptoms (21.7%), and sleep disturbance (23.5%) were significantly higher among exposed inhabitants than controls: (10%), (5%), (5%), (0%), (8.8%) and (10%), respectively.” It also showed that “the exposed inhabitants exhibited a significantly lower performance than controls in one of the tests of attention and short-term auditory memory”. 55
Another study showed that “people living in the vicinity of base stations report various complaints mostly of the circulatory system, but also of sleep disturbances, irritability, depression, blurred vision, concentration difficulties, nausea, lack of appetite, headache and vertigo.” 56
Some commentators have suggested that many of these symptoms are subjective or psychosomatic: that they result, for example, from anxiety about living close to a phone mast. Significantly, however, the study referred to immediately above showed a dose-response relationship: “[a] relationship between the incidence of individual symptoms, the level of exposure, and the distance between a residential area and a base station.” Moreover,
“This association was observed in both groups of persons, those who linked their complaints with the presence of the base station and those who did not notice such a relation.” 57 (emphasis added)
Another study had similar results: irritability, depressive tendencies and a lowering of libido, up to 100 metres from a phone mast; headaches, sleep disturbances and a feeling of discomfort, up to 200 metres from a mast; and fatigue 200 to 300 metres from a mast. It also found that the occurrence of seven of the reported complaints was significantly higher for women, up to 300 metres from a mast. The length of time spent living near a mast made no difference to the frequency of complaints. 58
A group of German doctors, writing of similar symptoms in their patients, point out that many of the symptoms are “in no way subjective ... sudden deafness, hearing loss, loss of vision, increased blood pressure, hormonal disturbances, concentration impairments, and others can be proved using scientific objective measures.” 59
They also emphasise that “[e]ven at 10µW/m2 (only 0.06 V/m average) many people are becoming ill”. 60 This is lower than typical exposure levels for wi-fi.
As mobile phones have only been in widespread use since 1997, and neurological diseases such as Alzheimer’s and Parkinson’s diseases are long-term in their development, there has been little epidemiological study of the links, if any, between these diseases and mobile phone use.
However, Hallberg and Johansson have shown a correlation between the rise in the incidence of Alzheimer’s disease in Sweden and the use of mobile phones. 61 In the USA, ten years earlier, Sobel et al connected Alzheimer’s disease with occupational exposure to radiofrequency radiation. 62
The main body of evidence linking radiofreqency radiation and possible senility is biological. 63 Research shows that microwave radiation
(a) causes DNA breaks, and
(b) increases the permeability of the blood-brain barrier.
(a) Lai and Singh have shown that even very low level microwave radiation leads to DNA breaks in brain cells. 64 Radiofrequency radiation does not itself have the energy to cause the breaks, but it does create free radicals, and these are known to cause such damage. 65
Lai points out that, while the accumulation of DNA damage can cause cancer, beyond a certain level of damage, a cell will die. Cumulative DNA damage in nerve cells of the brain is associated with Alzheimer’s, Huntington’s, and Parkinson’s diseases. 66
(b) It has been known for more than two decades that electromagnetic radiation has the potential to alter the permeability of the blood-brain barrier. 67 Nittby et al discuss 14 studies showing the effect. 68 The danger of a break in the blood-brain barrier is that the brain ceases to be protected from compounds in the blood that are harmful to the nervous system.
Researchers in Sweden have run experiments subjecting rats to microwave radiation at an intensity equivalent to that received by a mobile phone user. They have found that after two minutes the blood-brain barrier breaks down, allowing substances toxic to the central nervous system to cross over from the blood into the brain. 69 Consequent neural damage has also been demonstrated. 70 The researchers warn that these results mean that mobile phone use amongst young people may lead to degenerative brain diseases in middle age.
Research findings have also shown repeatedly that very low emission energy levels cause more leakage across the blood brain barrier than higher levels. 71, 72 Recent research has shown neurological damage at exposure levels of 0.12 mW/kg. 73 This is less than an eighth of the average exposure level of 1.00 mW/kg found 150200 metres from a mobile phone mast. 74 The researchers conclude that “the weakest fields are the biologically most harmful”. 75, 76
This means that neurological damage has been seen at levels of exposure at, and lower than, those typical of wi-fi.
There are many media articles on the internet linking cancer clusters with mobile phone masts. 77 A number of studies appear to confirm the link.
• In 2004 German doctors found that over a period of ten years patients who had lived within 400 metres of a phone mast had a significantly increased likelihood of developing cancer. Tumours appeared on average 8 years earlier than in the rest of the population. 78 Breast cancer appeared on average nearly 20 years earlier. Over a period of 5 years, the cancer rate within the 400 metre radius was three times as high as outside it.
• Cancer rates were also found to be markedly raised in a study of a community living near a phone mast in Israel. 79 There were more than four times more cases of cancer within 350 metres of the mast than further away. Cancer rates for women were more than 10 times the rate for the whole town.
The risk of cancer does not appear to be restricted to microwave radiation, but seems to attach to radiofrequency radiation generally. There have been several studies of cancer rates near radio and TV transmission masts. Rates of adult and childhood leukaemia in particular have been found to be raised.
Adult leukaemia was found in one study to have increased 1.83 times within 2 km of a TV mast in Sutton Coldfield. 80 Within 6 km of Vatican Radio, the rate of childhood leukaemia has been found to be raised 2.2 times. 81 Korean researchers have shown childhood leukaemia to be 2.15 times more likely 2 km from an AM transmitter than 20 km from one. 82 In Sydney, the rate of mortality from childhood lymphatic leukaemia (the most common type) near three TV towers is 2.74 times the rate further afield. 83, 84
Cherry refers to many other studies that have found similar effects, and other cancers, and emphasises that findings of a dose-response relationshipor the reduction in cancer rates with distance from a phone mastindicate a biological explanation. 85 The principal mechanism appears to be breaks in DNA and consequent chromosome damage that have been shown to result from radiofrequency exposure. The accumulation of DNA damage can lead to cancer. Cherry details much of the research, and comments, “[m]ultiple independent studies, in 32 papers, show significant increases in chromosome aberrations from RF/MW [radiofrequency / microwave] exposure. Four studies show dose-response relationships. This is more than adequate to classify RF/MW radiation as genotoxic.” 86