Cell Phone Use : Health Risks
By Dr Zafar M. Iqbal
We cannot seem to live these days without a cell phone. It gives us the kind of freedom that very few other electronic gadgets offer: it keeps us connected and helps us in case of an emergency at all hours no matter where in the world we are. So, other than our growing dependence and even addiction to it, what is this talk about the risks involved?
For the past two decades, a number of scientific studies have focused on potential health risks from our exposure to the radio-waves, or radiofrequency (RF) electro-magnetic fields, emitted by cell phones held so close to the brain as we talk.
These concerns recently got far more serious when a WHO arm, International Agency for Research on Cancer (IARC), announced that RF exposure are “possibly carcinogenic” to users, and classified it in Group 2b. This IARC Group lists about 266 agents/substances and mixtures (lead, car exhaust, dry cleaning solvent) that, under certain exposure conditions, can cause cancer in humans.
This IARC conclusion represents the recommendation of 31 scientific experts from 14 countries, who evaluated scientific literature (published and yet-to-published) on health risks from RF exposure emitted by cell phones. IARC did not quantify the increased risk of cancer but was influenced by a large multinational Interphone, long-term case-control study published last year in International Journal of Epidemiology (10 May, 2010). Although its conclusions are inconclusive, some other studies suggest slightly increased risks of certain kinds of brain tumors. National Cancer Institute (NCI) and other government agencies continue to monitor the health risk data on the frequency and extent of cell phone use over the years.
The evidence for RF carcinogenicity, is NOT as strong as that for 107 agents/substances/mixtures and certain viruses classified in Group 1 (“Carcinogenic to Humans” under certain defined exposure circumstances); this Group includes asbestos, benzene, high frequency ionizing radiation such as X-rays and gamma-rays. RF carcinogenicity evidence is also not as strong as agents/mixtures classified in Group 2a (“Probably Carcinogenic to Humans”) of about 59 agents and mixtures including PCBs, formaldehyde, UV radiation. IARC has 2 more Groups for agents, with lesser risks -- Group 3 (with over 500 agents with “Unclassifiable Carcinogenicity”) and Group 4 (those listed as “Probably Not Carcinogenic to Humans”).
The news of cell phone as “possibly carcinogenic” exploded around the world, and as happens often when scientific reports get disseminated in the popular press, the headlines tend to go beyond the prescribed cautions and defined limits. The impact was understandably global and huge, because there are estimated over 5 billion cell-phones in the world (over 70% of the current world population of nearly 7 billion) – including over 300 million in US (over 90% of its current population about 312 million), and 70 million in the UK, exceeding its population (about 63 million).
Cellular Telecommunication and Internet Association (CTIA), which represents the cell phone manufacturing industry, was quick to criticize IARC conclusions. It pointed out that cell phones produced in this country comply with strict governmental regulations, and stressed that long-term research by various government agencies has found that RF energy levels from cell phone are safe to the users, with no statistically significant increased risk for cancer. CTIA reminded that various household items, such as cordless phones, radio and TV, microwaves and infrared lamps that emit lower RF levels are safe for household use.
So, what do we do, as the controversy rages on? Let us check some other factors:
Cell phones now manufactured in the US operate between 1,800 to 2,200 megahertz (MHz) frequency, and in this range, the electromagnetic radiation is non-ionizing RF. This radiation emanates from the antenna, which in most current cell phones is inside the set. AM/FM radio and UHF/VHF TV also emit non-ionizing radiation but of a lower frequency than a cell phone does. Radiation at these frequencies is too weak to heat up human tissue or cause any damage. Still, what is more important is the relative amount of RF absorbed into the user’s head, or the specific absorption rate (SAR) of a cell phone. The Federal Communication Commission has SAR information on cell phones manufactured in the US in the past two years, which users can obtain from http://www.fcc.gov/oet/ea/fccid. It is of course important to know the SAR of your phone to know how much non-ionizing radiation is being absorbed into your head.
The exposure to RF depends on the number and duration of the calls, the cell phone traffic at the time, the distance from the nearest cellular base station, the use of hand-held device, and the quality of transmission. RF exposure may affect the following human cells and tissues: (i) Glial cells that surround the nerve cells (which could develop into malignant glioma), (ii) cells in the membrane, meninges, covering brain and spinal cord (in which meningiomas could develop), (iii) cells of the nerve in the ear (in which benign acoustic neuromas could develop), and (iv) salivary glands.
We don’t have to wait till the link between cell phone use and cancer is conclusively established. Here are some helpful hints we can take now as precaution:
Do’s: Keep your phone about 20 cm away from your head; this reduces by 98% of the radiation you will receive. Use cell phone when you are stationary, because when you are walking or driving, your cell phone uses more radiation to keep track of you. Keep the cell phone away from you while dialing, because most cell phones emit more radiation when the connection is being made. Remember, the more sophisticated your cell phone is, the more energy it emits to do different tasks.
Don’ts: Avoid long conversations, because you absorb a higher dose of radiation (a two-minute talk on the cell is reported to alter the brain’s normal electric activity up to an hour after that). Do not use the headset that comes with the cell phone, because that wiring can intensify radiation into your ear canal. Restrict cell phone use by children (“Mobi-kids”), because young developing nervous system could be more susceptible to accumulating radiation effects as they age and their use increases.
Do not use the cell phone when the signal is low (1 bar or less), because more energy is emitted in trying to make the contact. Do not use cell phone in elevators, cars or other metal enclosures, because they trap the radiation that might bounce back on you.
Since cell phone use will only increase and expand in the coming years, some precautions now cannot hurt us.