Some of you may have seen this man struggling to keep his balance inside a crowded city bus. He held the handrail with one hand, and with the other tried to display and sell, in his own words, “the only protection from being exposed to mobile radiation and, thus, cancer!”

“Almost all of you have been using mobile phones, but you don’t know that the radiation from these devices can cause cancer. Mobile phones emit radio waves. You can check it by taking your phone near your TV. You will hear a buzzing sound. This radio wave is a form of electromagnetic radiation which penetrates your brain and body when you hold the phone close to your ear. Scientists say excessive use of mobile phones this radiation can cause cancer,” the man said with panache.

“I am giving you the solution. You see this small plastic sticker. It is coated with ionised silver. If you paste it at the top (receiver) of your phone, it will block the radiation. You can check it. Just take your phone near your TV. You will hear no buzzing. It costs only Tk. 100,” the man made his sales pitch.

Does that small sticker really provide the solution to a problem for which researchers have been spending billions of dollars across the globe? And is there enough evidence to prove that mobile phone radiation causes cancer and other malignant diseases?

“The problem is that we still do not have that answer. A number of research publications say that mobile radiation is harmful for health, while there are others that debunk such claims. The problem is that all those studies are backed by rigorous scientific evidence. So, no definitive answer has been found yet,” said Dr Satyaprashad Majumder, professor of telecommunications engineering at BUET.

“And that sticker with ionised silver has nothing to do with stopping radiation! It just creates a small magnetic field so that radio waves are unable to attenuate the signal (the reason behind the halt to buzzing),” he said, when asked whether such stickers could prevent radiation.

Prof. Majumder said Bangladesh did not have any organisation that conducts research on the harmful effects of mobile phone radiation. “This sort of research needs huge funding and ultra-modern facilities which we don’t have at present,” he said.

“Also, such research must be conducted by a specialist team comprising experts from different fields including physics, telecommunication, and healthcare,” he added.

What is mobile radiation?

Prof. Majumder explained that a cellular phone is basically a radio that sends or receives signals on waves to or from a base station. The carrier signal generates two types of radiation fields: near-field radiation and far-field radiation.

Interestingly, living organisms, too, generate electromagnetic fields at the cellular, tissue, organ, and organism levels. This is called the biofield. “Research says that both near-field and far-field radiation from cell phones can hamper the human biofield,” he said.

Dr Akram Hossain, founder chairman of the oncology department of Bangabandhu Sheikh Mujibur Rahman Medical University (BSMMU), said that if the biofield was hampered by external radiation, human cellular energy would be used for body protection rather than body metabolism. This deviation from regular metabolism can cause serious health hazards, including cancer, he noted.

Dr Hossain said that The International Agency for Research on Cancer (IARC), a component of the World Health Organisation, has recently classified radiofrequency fields as “possibly carcinogenic to humans” based on limited evidence from human studies as well as from studies of radiofrequency energy and cancer in rodents.

Interestingly, the American Cancer Society (ACS) states that the IARC classification means that there could be some risk associated with cancer, but the evidence is not strong enough to be considered causal and needs to be investigated further, he noted.

“The problem is that the cell phone has become a part of our life. Several research studies backed by the huge mobile industry have constantly been trying to prove that cell phone radiation is not harmful. It is better to be careful and try to make calls with hands-free equipment," he said.

Eminent physicist Prof. Ali Asgar said cell phones emit radiofrequency energy, a form of non-ionising electromagnetic radiation, which can be absorbed by tissues closest to where the phone is held. The amount of radiofrequency energy a cell phone user is exposed to depends on the technology of the phone, the distance between the phone’s antenna and the user, and the extent and type of use, he added.

Does this cause cancer?

About the potential cause of cancer, Prof. Asgar said exposure to ionising radiation, such as from radiation therapy, has been known to increase the risk of cancer, but there is currently no consistent evidence that non-ionising radiation increases cancer risks.

He also said that renowned research organisations in Europe, America, and Japan had conducted several experiments on mobile radiation and published their results. “Those results, however, are not conclusive,” he added.

Internet sources said “The Interphone Study”, conducted by a consortium of researchers from 13 countries, was the largest health-related case-control study on the use of cell phones and cancer. The published analyses from this study have shown no statistically significant increases in brain or central nervous system cancers related to high instances of cell phone use.

However, most scientists agreed on one thing: if mobile phones are hazardous, children may be more vulnerable than adults to their possible ill effects.

Researchers say electromagnetic waves generated by a mobile phone penetrate up to four cm into the brain. Four cm into an adult brain is just the temporal lobe. There are not too many important functions in the temporal lobe, but more central brain structures are exposed in a child.

However, the data from clinical studies in children does not support this theory. The first published analysis came from a large case-control study called CEFALO, which was conducted in Denmark, Sweden, Norway, and Switzerland.

The study included children who were diagnosed with brain tumours between 2004 and 2008, when their ages ranged from seven to 19. Researchers did not find any association between cell phone use and brain tumour risk in this group of children.