About the Interphone Study on Cell Phone Radiation and Brain Cancer

A connection between cell phone radiation and brain cancer has been alleged nearly for as long as there have been cell phones. However, scientific research on the subject has, for the most part, been small-scale and with disappointingly mixed results. Since 2000, considerable hope was therefore invested in a major international research project known as the Interphone study, which published its most recent results in May 2010. Although it is by far the largest and most comprehensive study to date, Interphone suffers from sufficient flaws that it seems it will fail to satisfy the continuing need for clarity and confidence on this subject.

– About Cell Phone Radiation and Brain Cancer –

Over the past two decades, cell phones have gone from a professional luxury to a social ubiquity in most developed countries. According to Time magazine, no less than 270 million Americans now own and use a cell phone. It is perhaps not surprising that a relatively new and rapidly adopted technology has sparked fears in some circles that there will be unexpected negative health effects down the road.

In particular, critics of cell phone health issues have long feared that cell phones will lead to a rise in brain tumour rates in the general population because of the cumulative damage to the head caused by long-term exposure to the radio waves emitted by the phones while they are in use. While the amount of radiation delivered is actually negligible (and there is no dispute on that fact), there are concerns that the low dose delivered frequently over long periods of time, as cell phone users hold their phones to their heads repeatedly over the course of what will soon be decades, will eventually have harmful effects, such as genetic mutations leading to cancer.

– About the Interphone Study –

The Interphone study is a transnational effort to provide clarity and scientific understanding of this issue, adding weight to – or, conversely, challenging if necessary – a wide variety of previous smaller-scale studies which generally found no conclusive link between short-term cell phone use and brain cancers such as glioma. Scientists and subjects from thirteen nations participated in the Interphone study under the auspices of the International Agency for Research on Cancer and the World Health Organization, over a ten-year period between 2000 and 2010.

In 2007, the Interphone group published a preliminary report on its methodology and objectives in the European Journal of Epidemiology. Beginning in 2000, the group collected research from scientists in the participating countries on cell phone users who had developed brain tumors, parotid gland tumors, and acoustic nerve tumors (the nerve leading from the ear into the brain). In general, the objective of the study was a statistical analysis of the population under study, to determine whether, all else being equal, those with heavy cell phone use had a correspondingly higher likelihood of developing brain cancer. If they did, the logic went, then the cause of the increased prevalence of cancer would logically be cell phone radiation.

– Conclusions of the Study –

Beginning with a series of individual study papers published since 2000 and culminating in a report published in May 2010, the Interphone group has largely failed to identify a clear link between cell phone radiation and brain cancer. After the most recent publication, director Christopher Wild explained that the study had concluded that “an increased risk of brain cancer is not established from the data.”

The general conclusion of the Interphone study project was that the data could not justify either a decisive conclusion that there was no link between cell phone radiation and brain cancer, or that there was such a link. The general consensus in the medical news was that the Interphone study failed to provide clarity on the subject of cell phone radiation and brain cancer. Noted technology and science news website Ars Technica said the study “clarifies little,” while MSNBC described the study’s conclusions as “no answer, just fuzz.”

– Criticism –

Ambiguity was a safe position for the authors of the study, in light of the fact that they were dealing with an extremely controversial and potentially career-threatening subject through a data set that was, as they admitted, less than conclusive. However, advocates from both sides of the debate have tended to argue that the conclusions did not go far enough, given the data. One industry lobby group, the Mobile Manufacturers Forum, announced that the Interphone study proved the safety of cell phones, although this was not actually what the report stated (a finding of “inconclusive” is not the same as a finding of “safe”).

From those who have long held that cell phones do result in an increased incidence of brain cancers, the general perspective on the report was that it had decided to compromise for the sake of safety. (Scientists have careers and reputations, too, and often prefer not to rock the boat unnecessarily.) Berkeley’s Joel Moskowitz, in a paper timed to coincide with the Interphone report, argued that the Interphone data indicated that a moderate but measurable increase in glioma tumours occurred in those whose cell phone use exceeded a total of 1600 hours: an impressive record of cell phone use when the study began in 2000, but today, when cell phone use has increased by orders of magnitude, a much less surprising figure for the average cell phone user, spread out over a period of years. It also did not consider children, possibly more at risk, or tumours diagnosed after 2002 (according to Time magazine), meaning that if there is a long-term increase in brain cancer rates, the study’s data would have almost certainly under-represented that increase.

In either case, an inconclusive finding is a sure study that a larger, more comprehensive study is now necessary. The requirements for such a study are daunting, given that the Interphone study already involved analysis of thousands of cases in over a dozen countries. Nevertheless, regardless of one’s opinion on the safety of cell phones, an inconclusive finding in such a large study is evidence that further large-scale studies are necessary to provide the necessary level of clarity.