What is radiation? Is there too much unnatural radiation around us now?
The notion that cellphones are harmful to humans seems to have arisen from the often-misunderstood word radiation. Radiation in normal usage should not be associated with radioactivity or ‘ionising radiation’.
Just to refresh your middle-school memory, radiation is the transmission of energy in the form of waves, and since it has electronic as well as magnetic connotations, it is called electromagnetic radiation. Millions of such waves move around us and hit us all the time. In fact, visible light itself is a mix of many types of electromagnetic radiation. The range or spectrum of such waves includes those generated and/or used by:
- Radio, transistor or FM devices
- Bluetooth devices
- Satellites (for communication, remote sensing, etc)
- Wireless devices used by the police and defence forces
- Remote-controlled devices, cordless phones
- Magnetic resonance devices used for diagnosis of diseases
- Infrared imaging and night-vision devices
- RF telescopes
- Microwave transmitters
- Microwave ovens
- Cell phones
- X-ray machines and related diagnostic devices
- Atomic reactors
- Nuclear explosion
The sun is the biggest source of radiation in the form of visible light as well as ultra-violet radiation. Solar ultraviolet radiation is harmful to living beings, but, luckily, the earth’s atmosphere absorbs most of this radiation coming from the sun.
At one end of the radiation spectrum, there are radiations with very high energy – this type of radiation can ionise atoms and thus result in deformities in the genetic material, tumors and cancers. Atom bombs and leakage from nuclear reactors result in huge quantities of such radiation. X-ray machines work with such rays, and therefore a long exposure or leakage in X-ray set-ups can also result in serious health issues.
Though the radiation of a lower energy level does not ionize atoms, it can be absorbed by living beings. This can locally heat and damage tissues. Microwaves are this form of radiation. They do not cause tumors or cancers but can damage tissues because the water or oil contained in cells can absorb microwave rays and get heated.
The radio frequencies are at the other end of the spectrum and are considered the safest waves.
What type of radiation do the mobile phone devices and towers emit? Is it in the harmful range?
Mobile phones emit a type of RF radiation, which transmits energy far below the level that human bodies can safely tolerate. It is fully non-ionising. So, from ionising point of view, this is completely safe.
Cellphone radiation is much safer than that from microwaves, infrared, etc, the heating point of view also, because it has a very low energy level.
In fact, the US Food and Drug Administration states that the mobile phone radiation is safe for human beings:
“…the weight of scientific evidence has not linked exposure to radio frequency energy from cell phone use with any health problems… Cell phones emit low levels of radio frequency energy, a type of non-ionizing radiation. The available scientific data on exposure to radio frequency energy show no categorical proof of any adverse biological effects other than tissue heating. Public health data show no association between exposure to radio frequency energy from cell phone use and health problems.”
The matter is settled, you said?
I didn’t say that. Though the US and European health agencies and the WHO have said that the mobile phone radiation is harmless, they have shied away from saying so in absolute terms. What they have said is that there is no scientific evidence at present to prove harm from such radiation.
As we discussed above, mobile phone usage does not hurt in the two main ways (excessive heating, ionising). Yet, there are other ways mobile phones can impact our health. Consider these:
- Radiation absorption and Heat: Cellular towers, as well as phone devices, emit radiation in the range of 450 to 2700 MHz. When the radiation falls on the body, the body absorbs it, causing localised heating, and perhaps in some other ways not yet known.
There is a SAR (=Specific Absorption Rate) value attached to all mobile devices and tower equipment. National authorities and the WHO have defined the maximum SAR that a device or tower can have, and all manufacturers and service providers are required to follow them. However, in a survey in India in 2020, some towers were found to emit more radiation than the permissible limit. Please note that cell tower radiation goes down fast with distance, and therefore is not likely to harm people unless they stay close to antennas and at the same height.
- Though there is no clear evidence of mobile frequencies interfering with cardiac pacemakers, some instances of people reporting discomfort are reported.
- Though the radiation emitted by cell towers and mobile phones may be within the prescribed limits, regular and wrong use of mobile phones raise the probability of harm in other forms such as spondylitis (when the mobile phone is held between the neck and shoulder), eye strain (when used for a long time and at high brightness), sleep disturbance (when used for a long time before the bed time), local heating (when used while charging, tightly pressed to the ear or used for a long time), and so on.
- Since nerve signals are in the form of electrical pulses, there is a theoretical possibility of radio frequencies interfering with the nervous system, including the brain.
- Some vendors sell radiation shields and special phone cases, claiming that these guard against radiation entering the human body. These are found to be of no use; in fact, some of them have been found to increase absorption.
As explained above, there is theoretically a negligible chance of radio frequencies developing tumours and cancers. The experiments on human beings so far have not proved an association between the two. An association of low-frequency radiation with childhood leukemia has also been established. However, most of the studies have remained inconclusive in establishing a causal relationship of RF radiation with neural, endocrine and cardiac human biological activities. In one study, continuous and excessive RF radiation has been found to cause tumours in mice, but it is argued that such extreme conditions are not likely in real life.
In 2013, the International Agency on Cancer in Research (IARC) classified mobile phone frequencies as ‘possibly carcinogenic to humans’, but that has been contested as not based on evidence and prone to misinterpretation.
The final word
Mobile phones do not seem to cause major health issues if we do not use them for excessively long durations and in the wrong way. Similarly, mobile towers do not seem to be causing health issues if one is not too near the antenna for a long time. As regards radiation, it cannot be said conclusively that the instruments and their radiation cause no harm to human beings.
*About the author: This article has been contributed by MK. He does not like to call himself a rationalist but insists on scrutiny of apparent myths as well as what are supposed to be immutable scientific facts. Please don’t take the views of the author as the views of Raag Delhi.