A French study released last month that looks at the brain cancer risks associated with cellphone usage has once again ignited the long controversy about this new potential health hazard, which is linked to radiofrequency electromagnetic fields (RF-EMF) emitted by wireless devices.
Hand-held phone use has literally exploded over the past decade and has already reached 75 per cent of the world population. This is particularly true for Southeast Asia where Thailand already has more cell phone subscriptions than people living in the kingdom.
While the possible cancer-inducing effects of wireless technology should be considered a major public health concern, health agencies and medical associations still cite a "lack of scientific evidence" and continue, with some degree of complacency, to talk about mere "controversy". This sadly has resulted in a weak if not non-existent endorsement of preventive measures. But is it coherent and even ethical in 2014 to use the word "controversy" when the stakes involved are so high?
To address this question, four large studies on the brain cancer risk and cell phone usage need to be reviewed and every attempt made to come up with a clearer view of the current evidence. Today's article, the first in a two-part series, explores the issues related to brain cancer development and the effects of radiofrequency emission on the living cells in the body.
Brain tumours can be benign (non-cancerous) or malignant (cancerous) but fortunately account for a small percentage of cancers afflicting humans. They can occur at all ages but older people aged around 60 to 65 are primarily affected. Although incidence is rare, children can also suffer from these tumours and these are usually diagnosed before the age of 10.
The main cancerous brain tumours in adults are called gliomas, which take their name from the glial cells in the brain, were the main tumours found in the cell phone studies. Other tumours discovered in the trials were benign and included acoustic neuromas (tumours on the nerve that connects the ear to the brain and which is responsible for hearing and balance) and meningiomas (benign growths that arise from the membranes surrounding the brain). Unless treatment is initiated early with surgery, the prognosis of brain cancer is often severe because these tumours spread quickly within the brain and to other organs.
Importantly, a long period of latency (period during which the cancer remains dormant) that lasts several decades precedes the full-blown cancer stage.
This long latency period is roughly similar to that in lung cancer development. Lung cancer is also known to rapidly spread when it reaches its full-blown stage, though the period of latency may last 25 to 30 years.
In 1900, before smoking became common, lung cancer was a rare disease. In the western world the epidemic of lung cancer started 20 to 25 years after cigarette smoking became widespread. Likewise, a young adult who starts smoking at 20 will not be at high risk of lung cancer he/she reaches 45 to 50 years or above.
In much the same way, scientists consider that the RF-EMF exposure does not lead to direct DNA damage as that caused by potent ionising radiation such as x-rays. However, radiofrequency radiation does induce energy under the form of heat, which is absorbed by tissues closest to the phone. In repeated exposure, this heating effect has been shown to release oxygen free radicals, which are unstable and deleterious chemicals involved in the inflammation processes and cancer development. The underlying mechanism for possible tumour-inducing effect linked to RF exposure on the tissues in close proximity (the brain and ear in the case of hand-held phones) is indirectly demonstrated by the production of these harmful substances.
The second part of this article will look at pros and cons of cell phone and antenna station exposure as well as prevention. It will be published on July 1.
A French study released last month that looks at the brain cancer risks associated with cellphone usage has once again ignited the long controversy about this new potential health hazard, which is linked to radiofrequency electromagnetic fields (RF-EMF) emitted by wireless devices.
Hand-held phone use has literally exploded over the past decade and has already reached 75 per cent of the world population. This is particularly true for Southeast Asia where Thailand already has more cell phone subscriptions than people living in the kingdom.
While the possible cancer-inducing effects of wireless technology should be considered a major public health concern, health agencies and medical associations still cite a "lack of scientific evidence" and continue, with some degree of complacency, to talk about mere "controversy". This sadly has resulted in a weak if not non-existent endorsement of preventive measures. But is it coherent and even ethical in 2014 to use the word "controversy" when the stakes involved are so high?
To address this question, four large studies on the brain cancer risk and cell phone usage need to be reviewed and every attempt made to come up with a clearer view of the current evidence. Today's article, the first in a two-part series, explores the issues related to brain cancer development and the effects of radiofrequency emission on the living cells in the body.
Brain tumours can be benign (non-cancerous) or malignant (cancerous) but fortunately account for a small percentage of cancers afflicting humans. They can occur at all ages but older people aged around 60 to 65 are primarily affected. Although incidence is rare, children can also suffer from these tumours and these are usually diagnosed before the age of 10.
The main cancerous brain tumours in adults are called gliomas, which take their name from the glial cells in the brain, were the main tumours found in the cell phone studies. Other tumours discovered in the trials were benign and included acoustic neuromas (tumours on the nerve that connects the ear to the brain and which is responsible for hearing and balance) and meningiomas (benign growths that arise from the membranes surrounding the brain). Unless treatment is initiated early with surgery, the prognosis of brain cancer is often severe because these tumours spread quickly within the brain and to other organs.
Importantly, a long period of latency (period during which the cancer remains dormant) that lasts several decades precedes the full-blown cancer stage.
This long latency period is roughly similar to that in lung cancer development. Lung cancer is also known to rapidly spread when it reaches its full-blown stage, though the period of latency may last 25 to 30 years.
In 1900, before smoking became common, lung cancer was a rare disease. In the western world the epidemic of lung cancer started 20 to 25 years after cigarette smoking became widespread. Likewise, a young adult who starts smoking at 20 will not be at high risk of lung cancer he/she reaches 45 to 50 years or above.
In much the same way, scientists consider that the RF-EMF exposure does not lead to direct DNA damage as that caused by potent ionising radiation such as x-rays. However, radiofrequency radiation does induce energy under the form of heat, which is absorbed by tissues closest to the phone. In repeated exposure, this heating effect has been shown to release oxygen free radicals, which are unstable and deleterious chemicals involved in the inflammation processes and cancer development. The underlying mechanism for possible tumour-inducing effect linked to RF exposure on the tissues in close proximity (the brain and ear in the case of hand-held phones) is indirectly demonstrated by the production of these harmful substances.
The second part of this article will look at pros and cons of cell phone and antenna station exposure as well as prevention. It will be published on July 1.
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