Like the Phoenix rising from ashes, so is the “cell phones cause cancer” meme. The current claim is based on a study done with rats exposed full body for nine hours a day for several months. The result was a statistically significant increase in two types of tumors, gliomas and schwannomas. Gliomas are tumors in glial cells of the brain and are rare, the incidence in 2008 was less than 7 per 100,000. In this study the schwannomas were found in heart cells and are even rarer. Important also was the fact that there was a dose-response relationship. Higher intensity cell phone radiation produced a greater incidence of tumors.
So is it time to keep that phone on speaker and never, never carry it around in your bra? Maybe not, at least the bra part. Where as there were increased tumors observed in male rats, there was no increase in tumors in females regardless of the dose (intensity of radiation.) That in itself is a problem as both male and female rats have glial and schwann cells so why were only the males affected?
The bigger problem with a link between cell phones and cancer is the fact that it is biologically implausible. Cell phones utilize radio waves as do WiFi, TV, microwaves and others. This is the lower energy form of electromagnetic radiation that does not cause ionization and therefore doesn’t cause chemical reactions. A chemical reaction is required to cause a mutation in DNA and hence initiate cancer. Higher energy radiation known as ionizing is a well know cause cancer. Too much ultraviolet (UV) radiation from the sun is the most common cause of cancer. X-rays are also a known cause of cancer.
The history of cell phones and cancer is somewhat odd. In 1989 Susan Reynard , 31, was diagnosed with an astrocytoma, a tumor of the astrocytes which is another type of brain cell. The tumor, in the eyes of her husband resembled the outline of a cell phone – just like she held it to her head. She died in 1992 and her husband sued the phone manufacturer and service provider claiming a causal link between her cell phone use and the tumor which killed her. He lost the suit.
A number of studies with laboratory animals and epidemiological studies with humans have been been conducted over the years with variable outcomes. Studies with animals always suffer from the fact that there may be physiological differences between us and other animals, hence risk factors will be different.
Even without a controlled study the connection between brain cancer and cell phone use seems sketchy. Whereas the incidence of brain cancer has remained relatively steady over the past few decades, use of cell phones has increased several hundred fold. It is estimated that 91% of adults in the US use cell phones.
Epidemiological studies look at the relationship between disease and human population factors. The most accurate are prospective studies where a group a people are followed over a long time span to see if there is a correlation with a disease and their exposure. A prospective study concluded in 2011 confirmed this lack of a relationship. Thousands of participants across 13 countries were followed for close to a decade. The was no discernible relationship whatsoever between cell phone use and cancer.