Are cell phones killing us?

“You don’t have that cell phone next to your ear, do you?”

I’m talking to Sen. Mark Leno (D-San Francisco) about cell-phone radiation, and I admit I’m not listening hands free. “I didn’t have time to fire up my Bluetooth,” I explain. “Doesn’t your phone have a speaker?” he wants to know. I don’t know if I’m holding a hot little weapon that’s slowly boiling my brain or an innocuous tool, but I’m starting to feel slightly worried.

Leno knows the evidence linking cell-phone radiation to brain cancer and other harmful effects is inconclusive, but he’s concerned enough to have authored legislation that would require sellers to disclose, at the point of purchase, the amount of radiation a cell phone emits. As SN&R went to press, the Senate was expected to vote on the bill by June 4. Sponsored by the Environmental Working Group, Senate Bill 1212 calls for sellers to provide SAR values for phones. SAR stands for specific absorption rate, which is the level of radiation emitted from a cell phone and absorbed by the human brain and body. Cell phone SARs range from 0.2 to 1.6 W/kg (watts of energy absorbed per kilogram of body weight). The Federal Communications Commission’s upper limit for cell-phone SARs is 1.6 W/kg.

Many phone companies report SAR levels to the FCC, which posts them on its website. But even those who know the information is there have trouble locating it. The EWG also posts SARs on its website. But unless you have one of the most popular new cell phones listed on its top-10 lists of best and worst phones, be prepared for a lengthy search here, too.

Opponents of Leno’s bill—all the major phone companies, manufacturing and retailer associations, and a few others—complain it amounts to a de facto warning label. It’s also unnecessary, they say, since companies report SARs to the FCC, which regulates safety.

But there’s no requirement to give SAR information to cell-phone users. And that’s the point, Leno said: “It’s very simply about a consumer’s right to know.”

Since he’s been involved in the issue, Leno’s changed his own habits. He uses a headset or his phone’s speaker. He turns his BlackBerry off when it’s in his suit-jacket pocket longer than a few minutes.

Those precautions—plus texting more than phoning and buying a low-SAR-value phone—are the FCC’s recommendations to cell-phone users.

Should we be scared of our mobile phones?

The truth is that researchers don’t have the answer. Findings are inconclusive and often contradictory. Studies show, for example, that cell-phone radiation interferes with sleep, makes us sleepy and has no effect at all. Radiation emitted by cell phones has been linked to low sperm counts as well as shown to cause no damage. Researchers have even found a protective effect on the progression of Alzheimer’s disease from cell-phone use. And although there’s been much speculation, most research has failed to find a link to brain tumors.

Findings from the largest and longest study of cell-phone use and brain cancer, which were made public in mid-May, have done nothing to clarify the issue. The 10-year study, coordinated by the International Agency for Research on Cancer in 13 countries (but not the United States), looked at more than 7,400 people with brain tumors and compared their cell-phone use to about 12,000 similar people without tumors. Researchers conclude that overall, cell-phone users did not show an increased risk of tumors. About one-fourth of the study’s funding came from industry sources.

As soon as results from the so-called Interphone study hit the wires, the spin began. Federal agencies—the National Cancer Institute and the U.S. Food and Drug Administration—were among those discounting increased risk of brain tumors. Others took the researchers’ suggestion that heavy cell-phone users—30 minutes or more per day for at least 10 years—might be as much as 40 percent more likely to get a tumor called glioma, as an argument for caution, if not alarm.

These results didn’t change David Rocke’s mind about the threat from cell-phone radiation, however. For the distinguished professor in engineering at UC Davis and public health sciences at UC Davis’ Medical Center, “There is still no credible evidence of harm.”

Like a lot of attempts to explain harmful effects of substances on our health—think of the controversies over butter vs. margarine, drinking coffee or not—demonstrating that the low-frequency radiation emitted by cell phones has an effect on human health is extremely challenging. It’s not possible to select people at random, expose them to radiation and compare them with those selected for no exposure, like scientists do in drug trials. Researchers have to content themselves with studying populations of people—those who’ve developed brain tumors and others who haven’t—and then after the fact looking at factors that might explain a cause. These are called epidemiological studies, and they’re notoriously difficult to design and conduct. Even when researchers do find an association, their results must be confirmed by other research before they’re accepted.

These difficulties explain why Rocke and others find fault with much of the research on cell phone-radiation effects. But the real clincher for Rocke, who studies radiation biology at UC Davis, is that no one has yet demonstrated a mechanism by which radiation of this wavelength and low-energy damages human tissue. Rocke used the case against cigarettes and cancer to explain. There, population studies demonstrating a link were backed up by laboratory research that found the mechanism: Ingredients in cigarettes cause cancer.

Even though radiation is a continuum, don’t make the mistake of equating the low-frequency radiation emitted by cell phones with high-frequency radiation, such as X-rays, which can damage DNA. Rocke likens the impact of an X-ray on the body to being slammed by a 9-pound bowling ball. Cell-phone radiation is less than one-billionth as powerful, and Rocke suggests the cumulative effect would be closer to being covered one at a time by 9 pounds of feathers.

“If you don’t do anything where you don’t know the risks, you’d spend your entire life cowering in the closet with your head covered by a blanket,” said Rocke, who spoke via BlackBerry using a headset while he drove. “Personally, I’m quite happy putting a cell phone to my ear.”

“We are not saying cell phones are dangerous,” said Renée Sharp, the EWG’s California director. “It’s going to be unclear for years to come.”

“This is a huge health experiment—300 million Americans use cell phones—and we just don’t know the health consequences,” Leno said. “Until we know, I’m going to err on the side of caution.”