Friday, January 11, 2013

Beware the cellphone tower


Humans like to categorize time. Depending on who’s doing the categorization—historians, astronomers, geologists and others—time forms into eons, eras or ages. Some are familiar, others are strange: the stone age, the Cenozoic era, the Renaissance, the dark ages, the industrial age, the space age.
But nowhere in the Holocene, the era of humans, are you likely to hear of the electromagnetic age.
We should because we are in the middle of it, absorbing—by some estimates—perhaps 100 million times more electromagnetic energy than our grandparents.
The electromagnetic age defines modern life. If you watch television, use a telephone, surf the Internet, get a brain scan or switch on the microwave, you are using electromagnetic waves.
Infrared rays, x-rays, ultraviolet light, gamma rays, radio waves and visible light are all part of the electromagnetic spectrum. Of these, only visible light is discernible by the human eye. The rest are quiet, invisible waves of energy, differing from one another by the frequency, or length between wave crests.
The human body itself has an electromagnetic field. Although it’s very weak, the field is essential for keeping us healthy. What isn’t quite as healthy is the ceaseless bombardment by electromagnetic radiation from cellphones and cellphone towers. The latest alarm came earlier this week through the Hindustan Times (HT), which reported that Indian radiation limits for cellphone towers are 900 times higher than levels considered safe by international experts. This despite a September 1 2012 rule, raising India ’s cellphone-tower radiation safety limits by 90%.
Quoting the Bioinitiative 2012, a report released by 29 independent scientists from 10 countries (including India), HT said such radiation appeared to cause headaches, concentration and behavioural problems in children; sleep disturbances, headaches and concentration problems in adults.
Cellphone and cellphone-tower radiation is the most widespread fallout of the electromagnetic age and among its most contentious issues. There is no dispute that cellphone and cellphone towers subject us to greatly increased electromagnetic radiation. What is disputed—primarily by the industry—are the effects of this radiation.
A variety of studies in many countries indicate that cellphone towers should be sited between 300m to 500m from inhabited buildings. In Indian cities, where cellphone towers sprout on rooftops and walls, people sometimes live within 10m of an antenna.
While direct causality is difficult to establish, studies in countries as diverse as Spain, Germany, Israel, the US and India have noted an increasing incidence of cancers among those living near cellphone towers, notes a presentation made by Girish Kumar, a professor at the Indian Institute of Technology (Bombay). A 2004 Israeli study found a four-fold greater incidence of cancer among people living within 350m of a cellphone tower, in comparison to the country’s general population; among women that incidence increased ten-fold.
There does appear to be a correlation between the incidence of cancers and cellphone towers, but there is no direct evidence that these cancers are caused by the towers. Some argue that this is the same argument used for decades by the tobacco industry, which was finally forced to accept that smoking did cause cancer. But research on the medical effects of smoking is substantially more advanced than research on the effects of cellphone towers.
Kumar’s solution to possible radiation hazards has been to develop a variety of personal radiation shields, in the form of curtains, window films and table tops. He even has one in his pocket to diminish radiation from his cellphone.
And what of cellphones?
India’s department of telecommunications, on its website, has these guidelines: Keep your cellphone away from your body—to the extent that you can; use a wired or bluetooth headset; don’t press the phone against your head; use your cellphone on speaker mode; limit your calls; use text whenever possible; and when your phone is on, don’t carry it in a breast or pant pocket (a phone that is switched on sends a high-power burst of energy every one or two minutes to check its network).
Cellphones and their networks might have larger ecological effects, but there are, as yet, more questions than there is proof. For instance, might the disappearance of sparrows from our cities have anything to do with cellphone towers?
As we seek answers, it might be prudent for the government to do two things: one, tighten tower-radiation levels further; and, two, pressurize industry to reduce the power of cellphone towers. An industry that works on wafer-thin margins is unlikely to accede to these demands easily. The first will demand technology investments, the second will require more towers to compensate for weaker energy levels.
Caution, even if expensive, is a good idea. That’s why Indian cars now have seat belts and airbags. Like the car, the electromagnetic age has transformed humanity. It is now time to step back and closely study the deleterious effects of that transformation.

1 comment:

Unknown said...

Sir,
Can you pl provide the study materials for Basic RF concepts

Email:karthick.k125@gmail.com