By Dr Paul Giess
For many years the residents of Simon’s Town have had to live with poor cell phone coverage. This has resulted in complaints from locals (1) regarding health and safety issues, daily inconveniences and business communication issues. It has even led to some negative feedback on Tripadvisor for the town’s guesthouses (2). The solution to the problem is to extend the coverage from existing suppliers, such as Vodacom, by locating more base stations (i.e., cell phone masts) in the area. However, for various reasons this remains controversial in Simons Town, and indeed elsewhere, as detailed in this Peoples Post report (3).
The Peoples Post article concerns a specific application by Vodacom to erect an 11 metre high antenna in Murdoch Valley. While this would certainly improve coverage for local businesses and visitors some residents are concerned about the negative impact on property values and potential health risks. It is almost certainly true that property values will be affected for those living close to the proposed tower because cell phone masts are among the most controversial of all planning applications in South Africa and indeed elsewhere. Despite this across the country many residents are receiving monthly payments of up to R2,000 from the network providers to site masts on their properties, and schools and churches are competing with each other to host masts and take advantage of the increased revenue. Sometimes, as in Northcliff (4) and Eldorado Park Senior Secondary School (5) in Jo’burg, the potential health risks are leading to these decisions being questioned. Should we also be concerned in Simon’s Town?
One of the issues of most concern is the link between cell phone towers and cancer. Cell phone towers use radiofrequency (RF) waves to communicate with our cell phones. RF waves are a form of energy in the electromagnetic spectrum located between FM radio waves and microwaves.
It has been long known that exposure to ionizing radiation at the far right hand side of the spectrum can damage our DNA and cause cancer. We know that we should not receive too many x-rays in one year and we should cover-up or use sun cream to reduce exposure to UV radiation in strong sunlight. Like FM radio waves, microwaves, visible light, and heat, RF waves are forms of non-ionizing radiation. This means they cannot cause cancer by directly damaging DNA. RF waves are different from stronger types of radiation such as x-rays, gamma rays, and ultraviolet (UV) light, which can break the chemical bonds in DNA. The chemical bonds in DNA must be broken for a cancer to form following exposure to radiation. No controlled laboratory study has shown this to occur in cells following exposure to RF waves. Given our current level of knowledge, it is just not plausible to assume that exposure to RF waves can cause cancer.
Even if it were biologically possible for RF waves to cause cancer the exposure to the public from a cell phone mast is minimal. Like all forms of radiation, RF waves follow an inverse square law, which in practice means that there is a massive reduction in exposure with increasing distance from the antenna. Even just holding a cell phone in your hand and using the loudspeaker rather than pressing it to your ear can result in a huge decrease in radiation exposure. The same is true for cell phone masts.
Because of the inverse square law, public exposure to radio waves from cell phone tower antennas is minimal. The power levels are relatively low, the antennas are mounted high above ground level, and the signals are transmitted intermittently, rather than constantly. The International Agency for Research on Cancer (IARC) notes that exposure to the brain from RF waves from cell phone base stations (mounted on roofs or towers) is less than 1/100th the exposure to the brain from mobile devices such as cell phones.
There may be other effects of RF waves on biological systems. High levels of RF waves can cause a warming of body tissues (similar to the operation of a microwave oven), but the energy levels on the ground near a cell phone tower are far below the levels needed to cause this effect. Some studies (6) have reported the existence of a condition known as Idiopathic Environmental Intolerance attributed to ElectroMagnetic Fields (IEI-EMF), which is sometimes attributed to exposure to low strength RF waves, such as in the vicinity of a cell phone mast. The reported symptoms include headache, fatigue, stress, sleep disturbances, skin symptoms like prickling, burning sensations and rashes, and pain and ache in muscles. Often this condition is referred to as “electromagnetic sensitivity” as it is considered to only affect certain sensitive individuals.
The causes, and even the existence, of IEI-EMF is controversial. Many medical practioners believe these symptoms may be psychological rather than related to an environmental factor such as living near to a cell phone mast. In fact the best evidence that these effects are psychological anywhere in the world was provided by the response to an inactive mast in Johannesburg in 2009 (11). Residents of the Craigavon suburb claimed to experience several of the symptoms listed above once a mast was located in there area but were later informed that it was not operational during the period in question.
Like most studies of IEI-EMF, the British report from 2006 referenced above relied on self-reported symptoms from sufferers. Self-reporting is notoriously open to bias. Depending on their motivation, patients may exaggerate symptoms to make their situation seem worse, or they may under-report the severity or frequency of symptoms to minimize their problems. Patients may also simply make a mistake in reporting symptoms. When the University of Sussex (UK) undertook tests (7) using double-blind scientific tests (i.e., where the participant and the researcher are unaware of the actual treatment being supplied – only the experimental manger has this information so eliminating bias) the effect disappeared. In South Africa the Africacheck (8) organization has also reviewed the reports of health effects associated with the cell phone masts located in Joburg that were referenced earlier. They also concluded that all reported health effects, including cancer, were not likely to have been the result of RF waves from cell phone masts.
There remain many studies that are easily accessible where health effects are claimed to be demonstrated in populations situated near cell phone masts. When reviewing these sources of information it is important to consider that many of them may have a bias – they may be used to support the sale of a product whose manufacturers claim can reduce symptoms such as this one (9). On other occasions studies are poorly conducted, results cannot be reproduced and are not peer-reviewed, which is a vital part of the scientific process. The best way to make a judgement on the issue is to consider the conclusions of independent bodies that have reviewed all of these studies and can provide expert advice on the likely risks. The World Health Organization are the leading body in the world for this sort of information and their guidance (10) is included on Vodacom’s own website.
After reviewing all of the available studies the WHO have concluded:
To date, research does not suggest any consistent evidence of adverse health effects from exposure to radiofrequency fields at levels below those that cause tissue heating. Further, research has not been able to provide support for a causal relationship between exposure to electromagnetic fields and self-reported symptoms, or “electromagnetic hypersensitivity.”
Some people have argued that our knowledge of the effects of cell phone masts is so recent that the possible long term effects of exposure cannot be known. It is often argued that where there is a potential negative environmental outcome associated with a development we should apply “the precautionary principle”. This states that if an action has a suspected risk of causing harm to the public or to the environment, in the absence of scientific consensus that the action or policy is harmful, the burden of proof that it is not harmful falls on those taking the action. As the WHO guidance indicates, peer-reviewed scientific studies have demonstrated that the suspected risk of harm from cell phone towers is so low as to be almost non-existent. Given the continual accumulation of scientific evidence that cell phone masts are not harmful to public health and indeed have no plausible mechanism to cause harm, there is a strong case for allowing them to be sited in Simon’s Town. The business community and tourists will see an immediate improvement in their daily communication. More importantly, the lives that will be saved by improved emergency responses to accidents and criminal activity far outweighs the possibility of negative health effects.