A new report by a federal agency in the United States has ignited discussions over whether radiation from cell phones can actually cause the development of two types of cancer.

Conducted by the National Toxicology Program (NTP), the study discovered that radiation similar to the ones emitted by cell phones increased the risk of male rats developing tumors in their heart and brain. However, some experts remain unconvinced because of all the gaps.

The Nature Of The Study

The NTP is an interagency group under the Department of Health and Human Services whose task is to assess potential risks of chemicals.

In the study, NTP researchers placed rats in living chambers where they were exposed to different radiation levels — the type emitted by cell phones — for nine hours a day.

The exposure to radiation began when the rats were born and continued until they were 2 years old.

Experts found that roughly 5 to 7 percent of the male rats exposed to the highest radiation level developed schwannomas or Schwann cell tumors in their hearts. They concluded that the tumors were likely caused by radiation.

On the other hand, incidence of tumor growth among female rats was minimal, similar to the control group. Researchers have yet to understand why the results are different between male and female rats.

Why The Findings Are Doubtful

Experts from the U.S. National Institutes of Health are questioning the findings of this new study. They find it odd that no female rats grew tumors.

The unexposed rats also did not grow tumors at the rate predicted among a "normal" population, they said.

"I am unable to accept the authors' conclusions," says NIH Deputy Director Michael Lauer.

Lauer says the experiment appears to be substantially underpowered. He suspects that the few positive results reflect false positive findings.

Should We Dismiss The Study?

The authors of the new report believe that given the number of people who use communication devices today, even a tiny increase in the incidence of cell phone radiation-related disease have broad implications.

Biochemist Jerry Phillips of University of Colorado, who has experience in his own lab trying to understand the effects of radio-frequency radiation (RFR) on rats, said all the study does is provide few answers and raise more questions.

"If you look at all of the research being done on this, it's all from outside this country," Phillips tells Scientific American.

He says people want to believe that technology is safe.

"I do. I would love to believe it, but I know better," he adds.

The initial results of the NTP study were published on May 27. Complete findings will be released by fall 2017.

Photo: Alan Wolf | Flickr