Q. Do cell phones really cause brain cancer? Do you think the Philippines will soon have an epidemic of brain cancer because Filipinos use cell phones very extensively?
   
--Mark J., San Pablo City

A. Cell phones emit electromagnetic radiation because they send messages via radio waves, which consists of radiofrequency (RF) energy.

There are two forms of electromagnetic radiation, ionizing and non-ionizing.

Ionizing radiation, which is exemplified by x-rays and gamma rays can dislodge atoms and molecules from cells and tissues and are therefore harmful to the body. They can cause radiation sickness and, in the long term, cancer.

Non-ionizing radiation, on the other hand, which is exemplified by visible light, microwave radiation and radiofrequency (RF) energy, causes some heating effect, but usually not enough to cause any type of long-term damage to tissues. Hence, RF energy, which cell phones emit, is theoretically safe. However, with the geometric increase in the number of cell phone users worldwide, there is a growing concern among experts on whether the amount of exposure to RF energy of frequent cell phone users is still safe or enough to cause adverse health effects.

Of prime concern is the effect of RF energy on the brain because cell phones are often placed close to or against the head during use. In particular, experts are wary about the development of brain tumors including cancers among frequent cell phone users.

Numerous scientific studies on the relationship of cell phone use and the risk of developing benign and malignant brain tumors have already been undertaken. Most of these studies conclude that there is no evidence to support a link between cell phone use and brain tumors.

However, a few,  including an epidemiological study (2004) by a  Swedish scientific team at the Karolinska Institute, suggested that regular use of a mobile phone over a decade or more was associated with an increased risk of acoustic neuroma, a type of benign brain tumor.  In 2007, Dr. Lennart Hardell, from Örebro University in Sweden, reviewed published epidemiological papers and found that cell phone users had an increased risk of malignant gliomas and a higher rate of acoustic neuromas. He further noted that tumors are more likely to occur on the side of the head where the cell handset is used and that one hour of cell phone use per day significantly increases tumor risk after ten years or more.

In short (and this is in answer to your first question), existing evidence for or against the suggested link between cell phone use and the development of brain tumors are inconclusive. Cell phones have not been around long enough for scientist to be able to monitor large number of cell phone users for the length of time it might take for brain tumors to develop. In addition, most of the studies so far undertaken have numerous limitations including subject bias and lack of verifiable data regarding cumulative effect of RF energy exposure over time. The only thing on the subject that experts agree on is that further studies are needed before any conclusions can be drawn.

Meanwhile, while we don’t know yet whether or not cell phones can cause brain cancer, perhaps it is best that we limit our use of these gadgets. This should be especially true among children because they are likely to accumulate many years of exposure to RF energy during their life and also because their nervous system is still developing and is at greater risk of getting harmed.

As regards your second question, even if RF energy from cell phones can cause brain cancer, it is unlikely for this disease to reach epidemic proportion in the Philippines. We Filipinos hardly use our cell phones to make voice calls. We use them to text, a habit that exposes us to very little amount of RF energy because when we text, the cell phone antenna—the part of the phone that emits RF energy—is far from our body.

(Email inquiries on health matters to: medical_notes@yahoo.com or wellbeing@mb.com.ph.)