Bad News − Cell Phones May Cause Cancer

People love their cell phones. In fact, a recent survey by Motorola found that 54% of respondents would save their smartphone over their cat if a fire broke out. We tend to take for granted that our phones are user-safe. However, the truth is we really have no idea how significant the danger of our exposure to cell phones can actually be.

A New Cancer Study
The National Toxicology Program (NTP) recently completed a major $25 million study over 2-and-a-half years in which they investigated the possible health hazards the cell phone radiation could have on mice. They specifically used the radio frequencies and modulations (RF-EMF) currently employed by the United States mobile industry.

The NTP study found that the exposure to cell phones increases the incidences of gliomas (brain cancer) and schwannomas of the heart in male rats. The increase was notably small, about 3-4%, but since these tumors are rare, the findings are significant. The radiation level the mice received was not much different from what humans are exposed to when they use cell phones.

In the United States, of about 25,000 malignant brain tumors diagnosed each year, 80% are gliomas. Malignant brain tumors are the most common cause of cancer deaths for people aged 15 to 39.
The Food and Drug Administration (FDA), which is the agency charged with regulating the health aspects of consumer products, reports on its website that there is, "no evidence linking cell phone use with the risk of brain tumors." However, the FDA does acknowledge some risk associated with carrying cell phones too close to the body due to the phones' heating effect.

Controversial Human Studies
There have been 3 case-control studies conducted since 2010, which have all been positive (meaning increased cancer was found) in the highest exposure groups. In two of the studies, the tumors were found to occur on the same side that the cell phone was situated. However, these studies were also subject to recall bias. This means when people were asked about their mobile phone usage, the individuals with tumors could have exaggerated their usage.

Another study showed high relative risks when comparing an exposed group to a non-exposed group. This means there should be an increase in cancer in the general population. However, this has been controversial.

In 2011, the International Agency for Research on Cancer (IARC) appointed an expert Working Group to review all available evidence on the use of cell phones. The Working Group classified the mobile phone use as, "possibly carcinogenic to humans," based on limited evidence from human studies, inadequate evidence from studies on the radiofrequency energy and cancer in rodents, and contradictory evidence from mechanistic studies.

The American Cancer Society (ACS) states that the IARC classification means that there could be some cancer risk associated with radiofrequency energy, but the evidence is not strong enough to be considered causal and needs to be investigated further.

The Importance of the NTP Study
The NTP study is the first in which there is a positive result. All of the previous long-term studies in mice have been negative. However, the difference between this research and the former ones is that the length and magnitude of exposure in the NTP study were increased.
For example, one previous survey used almost the same magnitude of exposure utilized by the NTP (1.5-4 Watts/kilogram) but only exposed the mice for two hours per day. The recent NTP study exposed the mice for 9 hours per day, which best represents the typical cell phone use of humans.
Another research used a whopping 21-hour exposure per day but with a magnitude that was 10 to 20 times less than that in the NTP survey. Also, some of the previous studies used a different strain of mice. It is well known in the scientific community that different strains of mice do not always respond the same to environmental exposures.

Critics of the Study
Some people have been critical of the NTP study. The study found no tumors in the control (unexposed) group. Critics argue this inflates the chances of a false-positive finding (meaning a certain result seems to have occurred, but really didn't). Also, the rats exposed to radiation on average lived longer than those that weren't. Some reviewers argued that the study should have given more weight to that fact.
Another criticism is that there were no positive findings in the female mice. This again suggests that there could be a false-positive result.
However, the most likely conclusion, despite the criticisms, is that the exposure to RF-EMF caused the tumors seen in the male mice in the NTP study. With the positive case-control studies seen in humans, and now a similar positive finding in a well-conducted laboratory study in mice, the evidence that cell phones can cause cancer has been significantly strengthened.
This means that the mobile phones can probably cause cancer in humans. But factors, such as the duration, the proximity and the level of exposure also matter. It is best to keep a safe distance from your cell phone and decrease the level and the extent of exposure.

What Can You Do?

• Keep the cell phone away from your head as much as possible.
• Use a microwave radiation protection shield.
• Carry your cell phone in your purse or backpack rather than in your pocket.
• Limit its use in poor reception areas.
• Turn off your phone when you are not using it.
• Limit your child's exposure to cell phones. They will have longer exposure over their lifetimes.
• If you are concerned, don't use a cell phone.

Conclusion
The bottom line is that the cell phone use can probably cause cancer with enough close exposure of a sufficient magnitude for a long enough period of time. We still need more data to understand the level of exposure that is of concern for humans. We also need more studies on Bluetooth devices and Wi-Fi to understand their risks as well. Until more information is gathered, the best thing you can do is limit your exposure to cell phones by following the tips provided above.