Non-Ionising Radiation: A Silent Killer
Independent
Writer: Shamima Karim Choudhury, Professor of Physics, Dhaka University
August 20, 2002
Non-ionising electromagnetic radiation commonly termed EMF is that part of the electromagnetic spectrum that does not have sufficient energy to ionise atoms and molecules. The visible light has wavelength range of 400 nm -700 nm. Non-ionising electromagnetic radiation such as infrared, microwave, radio frequency (RF) etc. has wavelength longer than the visible light. RF and microwave energy is used in the industrial, scientific and Medical (ISM) sectors, broadcasting and communications, electrical power distribution etc. where unwanted exposure from leaked Electromagnetic Fields (EMF) and waves may be a problem.
Where do EMF emissions come from?
Electricity is the unseen helper of our times. It is taken for granted most
of the time but it may be sometimes harmful. EMFs are stronger relative to
the strength of current. However its intensity falls off quickly with
distance from the source. Magnetic field arises due to difference in
currents coming in and going out of a home supply. Homes located near high
voltage overhead transmission lines can be a concern as well. The electric
power industry is supposed to look for ways to reduce the public's exposure
to the lines' magnetic fields. It may be mentioned that the electric field
can be neutralised by earthing, but the magnetic field cannot.
Everyone is most likely extensively exposed to EMFs when --
* Uses a computer or a mobile phone, a photocopier or a fax machine
* Watches T.V. or listens to the hi-fi
* Uses a hairdryer or a vacuum cleaner
* Or a train, the tube or an aeroplane for that matter
* Lives or works in a big city or near electrical power lines
How serious can EMFs be?
The known effects of exposure to non-ionising radiation will depend on three main factors such as Frequency, Intensity of the EM fields and Period of exposure.
EMF's may be accountable for: Stress, Fatigue, Lack of Concentration and Focus, Low Energy and Vitality, Irritation, Emotional Swings, Mood Swings and maybe even more serious health hazards.
Several other problems have also been observed in people who spend more than four hours a day in close proximity to an unprotected Video Display Terminal (VDT) : stress, headaches, irritability, insomnia, eye strain, eyesight decline, abnormal general fatigue, decrease in productivity and in the natural resistance of the immune system, decline in libido, disorders in the menstrual cycle, and hormonal disturbances.
Scientific studies world-wide show that man-made electromagnetic field radiation to which we are nowadays one million times more exposed than our grandparents were -- may have adverse effects on our health and well-being.
Why Man-Made EMF is Harmful?
Many scientific studies demonstrate that our bodies have a complex electromagnetic system that is responsible for maintaining and repairing vital physical functions. In order to do its job the life system has evolved to interact with external electromagnetic fields - like those naturally generated by the earth and sun.
In the last fifty years, man has created a new radiated environment, which virtually replaces the natural world. This new electromagnetic environment is so pervasive and intense that at least one scientist estimates that an average person is now daily exposed 100 million times the electromagnetic radiation of his grandparents.
We are the first generation forced to adapt to these man-made electromagnetic fields. Every day, our bodies are constantly inundated by radio and television broadcasts, by cellular phone signals, by radiation from computers and other electrical appliances, by the force fields emitted by household wiring, and by transmission lines strung along and below city streets.
The body's electromagnetic system possesses a remarkable ability to adapt to rapidly changing environments. This is often called the body's "innate intelligence." But when environmental forces chronically bombard the body, the functioning of this innate intelligence can become compromised, which further weakens the body's ability to cope.
Recent scientific research indicates that man-made electromagnetic fields can affect health. Exposure to this radiation may induce discomfort and stress, causing personal performance to suffer. How can we cope with the negative effects created by manmade radiation? When our bodies are not overwhelmed, we are stronger and possess a natural inununity to the many different types of environmental stresses, including electromagnetic fields. The essential key to high levels of well-being and personal performance is to consistently maintain a vital innate intelligence.
The consequences of living in our EMF world may not be known for decades. Virtually all research on the serious health effects of man-made EMF has come to the conclusion that the adverse health responses from EMF are from long term cumulative sources.
Major Concerns:
Major concerns have been expressed that exposure to extremely low frequency (ELF) fields at power frequencies (50/60 Hz) could lead to an increased incidence of cancer in children and adults, or other adverse health effects. The evidence comes primarily from residential epidemiological studies. These studies suggest that children exposed to ELF magnetic fields have an associated increased risk of leukemia.
As has been mentioned earlier Radio Frequency (RF) fields are used in many facets of everyday life, such as radio and TV transmission, telecommunications (eg mobile telephones), diagnosis and treatments of disease and in industry for heating and sealing materials. With the rapid introduction of mobile telecommunications devices, especially among the general public, there has been a focus on the problems associated with near field RF exposure to the head from the small radiating antenna of mobile phones. In addition, concerns persist that exposure to pulsed and amplitude modulated RF fields may cause specific health effects.
As societies develop, greater use of certain technologies leads to increasing exposure to static electric and magnetic fields. This is especially the case in industry, transport, power transmission, research and medicine. Possible health effects from static fields have never been properly assessed. Given the rapid expansion of medical devices and imminent introduction, potentially on a large scale, of magnetic levitation transport systems that use strong static magnetic fields, any health impacts need to be properly assessed.
As part of its charter to protect public health and in response to public concern over health effects of EMF exposure, the World Health Organisation (WHO) established the International ENT Project to assess the scientific evidence of possible health effects of EMF in the frequency range from 0 to 300 GHz. It is part of the EMF Project's mandate to encourage a focused research programme to fill important gaps in knowledge and to facilitate the development of internationally acceptable standards for EMF exposure.
Are Computers and TV Screens safe?
What if the CRT screen turns out to be one of the main culprits, of many afflictions of modern civilisation, such as abnormal general fatigue, neuropsychological disorders, increased absenteeism, loss of productivity, declining ability to concentrate and to memorise, aggression and scholastic problems in pre-pubescent children, predisposition to dyslexia, and lowered spermatogenesis?
Doctors, scientists, politicians, teachers, and parents today worry about the major role played by CRT screens in our daily environment, in particular for children. We live in an age in which the number of satellite, telephone, and cable networks is on the increase and where the computer is the monarch. Despite the rising popularity of the Internet (more readily available to larger segments of the population) and the risks connected to CRT screens, which are recognised by scientists, the possibility of harmful effects is only rarely mentioned, and more often, simply denied.
Fire is dangerous and so is radiation. But we cannot go without these. Radiation has been an integral part of our life. We can only be cautious to save ourselves from its harmful effects. Our use and abuse of modern radio frequency and microwave technology for our comfort can result in permanent discomfort. We have to make a balance between our need and want. Those who spend long periods of time on their hand-held mobile phones could consider holding lengthy conversations on conventional phones and reserving the hand-held models for shorter conversations.