Overwhelming evidence that cell phone "radiation" does *NOT* cause cancer

This week Nick Bilton of The New York Times wrote a terrible article irresponsibly suggesting that cell phone "radiation" may cause cancer. I place the word "radiation" in quotes because cell phone radiation is very different from the ionizing radiation that is known to cause cancer, and this misrepresentation is just one example of the major errors of both omission and commission that plague the piece.

Bilton hedges his position somewhat using words like "may" or "possibly", but these modifiers do not change the substance of his assertions. The word "may" signifies a probability anywhere between 0 (say 0.01%) and 1 (say 99.99%), and Bilton certainly suggests that the probability that cell phone "radiation" causes cancer is far greater than the probability that an expert would assign to it (i.e. statistically indistinguishable from 0). The article is full of pseudoscience and scare-mongering both of which can have negative consequences with respect to any public health proclamation.

There are multiple major problems with the article including the following:

• Does not distinguish between non-ionizing radiation (cell phones, microwave ovens) and ionizing radiation (X-rays, gamma rays)
• Makes poor analogy to smoking
• Incorrectly interprets conclusions of IARC report
• Cherry-picks data much of which comes from a single lab
• Insinuates opposing studies suffer from conflict of interest
• Extensively quotes a crank

Each issue alone is damning, but taken together they indicate biased reporting. Rather than engaging in a point-by-point rebuttal of the specific claims in the article, I will summarize the existing scientific knowledge on this topic.

1. There is no evidence that non-ionizing radiation causes cancer (NCI):

"Exposure to ionizing radiation, such as from radiation therapy, is known to increase the risk of cancer. However, although many studies have examined the potential health effects of non-ionizing radiation from radar, microwave ovens, and other sources, there is currently no consistent evidence that non-ionizing radiation increases cancer risk (1)."

2. Medical studies in aggregate show no association between cell phones and cancer:

This point is best made by a figure from a 2009 meta-analysis of the studies on this subject (Figure 1). The y-axis is the odds-ratio (OR) that cell phone usage is associated with brain cancer; an odds-ratio of 1 indicates no association. It is clear that the vast majority of studies exhibit an odds-ratio close to 1 (within the error bars). The biggest exceptions are two studies from the Hardell lab. When aggregated together, the pooled OR estimate is very close to 1. When the Hardell lab data is excluded, the pooled estimate is slightly below 1 i.e. people who use cell phones have a slightly lower risk of brain cancer. Both pooled estimates are statistically indistinguishable from 1 (no effect).

The Hardell lab "has been criticised for publishing the same data in multiple papers, inconsistently reporting data such as sample sizes, and having implausibly high response rates to its questionnaires" (link).

3. No noticeable increase in brain cancer despite huge increase in cell phone usage:

'If mobile phones increase the risk of brain cancer, the rates of this disease should be skyrocketing since mobile phone use has risen dramatically over the last few decades. But studies in the US, New Zealand, Denmark, Norway, Sweden and Finland have found no such trends. In the UK, the incidence of brain cancer has been flat for the past few decades. A recent English study concluded that "the increased use of mobile phones between 1985 and 2003 has not led to a noticeable change in the incidence of brain cancer in England between 1998 and 2007."' (Ed Yong)

4. The leading experts have concluded there is no connection between cell phones and cancer (NCI):

"The National Institute of Environmental Health Sciences (NIEHS) states that the weight of the current scientific evidence has not conclusively linked cell phone use with any adverse health problems, but more research is needed.

The U.S. Food and Drug Administration (FDA), which is responsible for regulating the safety of machines and devices that emit radiation (including cell phones), notes that studies reporting biological changes associated with radiofrequency energy have failed to be replicated and that the majority of human epidemiologic studies have failed to show a relationship between exposure to radiofrequency energy from cell phones and health problems.

The U.S. Centers for Disease Control and Prevention (CDC) states that, although some studies have raised concerns about the possible risks of cell phone use, scientific research as a whole does not support a statistically significant association between cell phone use and health effects."

In summary, there is an overwhelming body of evidence that leads to the conclusion that cell phone "radiation" does not cause cancer.

As a postscript, The New York Times has issued the following editorial addendum to the Bilton article:

"The Disruptions column in the Styles section on Thursday, discussing possible health concerns related to wearable technology, gave an inadequate account of the status of research about cellphone radiation and cancer risk.

Neither epidemiological nor laboratory studies have found reliable evidence of such risks, and there is no widely accepted theory as to how they might arise. According to the World Health Organization, “To date, no adverse health effects have been established as being caused by mobile phone use.” The American Cancer Society, the National Cancer Institute, the Food and Drug Administration and the Centers for Disease Control and Prevention have all said there is no convincing evidence for a causal relationship. While researchers are continuing to study possible risks, the column should have included more of this background for balance.

In addition, one source quoted in the article, Dr. Joseph Mercola, has been widely criticized by experts for his claims about disease risks and treatments. More of that background should have been included, or he should not have been cited as a source.

An early version of the headline for the article online — “Could Wearable Computers Be as Harmful as Cigarettes?” — also went too far in suggesting any such comparison."

Figure 1. Odds ratio of association between cell phone use and glioma brain tumors. An odds ratio of 1 indicates no difference in brain tumor incidence between cell phone users and non-users. Error bars represent the 95% confidence interval. A) The upper graph describes data from short-term cell phone use (less than 5 years. B) The lower graph shows data from long-term cell phone use (greater than 5 years). Graph taken from Ahlbom et al. 2009.