With the ever-increasing number of people using cell phones these days, along with the increased duration of time for which such devices are being used, it has become a concern to understand the implications of such use on health and diseases.
Cell phones and all other mobile devices use a form of electromagnetic fields to transmit and receive information. They emit radio-frequency radiation more commonly called radio waves for that purpose. All the waves in the spectrum of electromagnetic radiation have been divided based on their energy levels into two categories, the stronger, more powerful ionizing radiation and the weaker, low frequency, low energy or non-ionizing radiation. Ionizing radiation, like the cosmic rays, have been proved to be hazardous to humans and animals as these radiations cause the breaking down of certain bonds in the DNA and cause changes in the genetic material to cause mutations that lead to cancers. Non-ionizing radiations, on the other hand, do not cause such changes in DNA; hence it has been believed for a long time that they are safe.
The frequency of radio-frequency radiation ranges from 30-kilohertz to 300 gigahertz. Electromagnetic fields used by all telecommunications including cell phones, radio transmitters, and televisions comeunder the range of radio frequency radiation. The human body can absorb these radiations depending upon the distance from such devices. The amount of radiation energy absorbed by the body is measured in units called Specific Absorption Rate (SAR).
Other non-ionizing radiations include the microwaves. Studies have shown that this non-ionizingradiation causes no effect on the DNA of exposed individuals and the only effect such radiations have on the human body is heating up under prolonged exposure to high energy waves. Heating up of food in the microwave ovens is a demonstration of the said effect. The amount of radiation that a cell phone emits is generally not high enough to cause such effects.
Many factors have to be taken into consideration in order o measure the amount of radiation a person might absorb from a cell phone. Some of these include:
duration of time for which the device is being used
distance from which it is used, for example, the amount of exposure may differ if you are using a hands-free device like blue-tooth or headphones
Model of the phone, as cell phones have different doses of radiation exposure depending on their SAR
Distance from the cell tower, which transmits the highest amount of radiation
Amount of network traffic in the area
Head and neck tumors are the ones that are studied the most in respect to cell phone radiation, as this is the area nearest to the devices while talking on the phone. A malignant tumor of the brain called a "glioma" is related to the coverings of the brain. A "meningioma," is a tumor surrounding the brain and spinal cord. A tumor related to the nerve that transmits auditory or hearing signals in the inner ear is called a "vestibular schwannoma" or "acoustic neuroma," and tumors of the parotid gland have been speculated to have a probable association with radiation exposure due to cell phones.
Epidemiological studies and what they show:
it is the largest case-control study related to health, evaluating data from 13 countries. It studied cell phone usage and head and neck tumors.
Various analysis of the study showed no significant association between head and neck tumors and cell phone radiation, only one analysis showed an increased incidence of intra cranial gliomas, but the researchers found the findings inconclusive.
it studied the association between cell phone billingand the incidenceof head and neck tumors. It showed no association between head and neck tumors and cell phone users even up to 11-13 years.
A million women study:
it was a prospective cohort which showed an increased incidence of acoustic neuroma with cell phone usage but on later follow up, the association was decreased.
One study showed there was increased glucose metabolism on the side of the brainwhere the cell phone was used. Another study showed the opposite effects. The difference in results could be due to non-consideration of other factors like temperature. Implications of such changes arealso not significant.
A study by the U.S. National Toxicology Program (NTP) was conductedon mice and rats. It showed that exposure to radio frequency increased the risk of schwannoma in the heart of male rats while the female rats and mice were not affected. This tumor occurs in the cells of the rat’s heart which are similar to cells in the human central nervous system and found in acoustic neuroma. But still, the results are inconclusive, and the amount of radiation exposure used in the experiment was so high that there is no significant risk to humans at the present levels of exposure.
Human studies have suggested a possible link but no conclusive evidence toward an association between brain tumors and cell phone exposure.
Considering all the information, it is better to use certain measures to protect yourself from cell phone radiation like limiting the amount of time spent on phone calls, putting your phone in airplane mode whenever not in use, using earphones to decrease the amount of radiation exposure, use direct communication or landline in case of long conversations.