You may have heard rumors about the safety of cell phones, especially if you’re pregnant.
To find out the truth, we talked with Leeka Kheifets, PhD, a professor at the UCLA School of Public Health, who studies the low-level energy from cell phones.
First of all, Kheifets hastens to note, she isn’t trying to say cell phones are bad, or that people shouldn’t use them. “I think it’s a great technology,” she notes. “Lives have improved because of it.” But they’re increasingly everywhere. If cell phones do have some health effect, then it’s not just the person using them who may be harmed — it’s everyone around them, including their children.
That very ubiquity means it’s worth studying, she points out. “Exposure is getting higher in many ways,” she says, “so it pays to consider whether it might have some other, unintended effects.”
Your cordless phone and cell phone, microwave, even your television and remote control — all emit invisible energy. A panel of the World Health Organization (WHO) calls the waves emitted by common household electronics “electro-smog.” Even the electrical outlets in your home create mini electrical fields. (The WHO has a helpful explanation of the different forms of energy here.)
Yet, to put this in perspective, the WHO panel points out that a cellular phone is permitted by safety standards to emit, at most, just a fifth of the energy (10 watts per square meter) leaked by the average microwave oven (50 watts per square meter). The sun at noon, by comparison, is pouring down 1,370 watts per square meter of energy on all of us.
Meanwhile, TVs and radios emit the same radiofrequency waves cordless and cellular phones do — and we’ve lived with radios for a century, with no discernible health effects.
High-energy radiation, such as that found in x-rays, does cause definitive harm through heating the body. It’s why doctors caution everyone to limit x-rays throughout a lifetime. The same form of radiation is used to kill cancer cells, and is why radiation therapy is difficult to undergo — it kills healthy cells right along with the cancer.
Yet these forms of energy are dramatically different from those we’re exposed to in everyday life — primarily because the heating power of electronics is virtually nonexistent. Still, some scientists wonder whether there’s at least a theoretical risk from the extremely low energy emitted by common electronics. “We know that it has an effect at high intensities, right?” Kheifets says. “The question is whether it has any effect at low intensities.”
The problem: scientists don’t really understand how cell phones or other electronic devices could affect human health. How exactly they might — the mechanism of action — simply isn’t clear, and no studies have reported consistent symptoms.
Some people living near cell phone towers have reported headaches and trouble sleeping. And at least one controversial study linked cell phones to brain tumors. Yet multiple reviews over decades conclude that data on health effects from low-level energy is inconsistent and inconclusive, even with heavy use. A 2011 study also found no relationship between cell phone use in children and brain tumors.
And though a new, headline-grabbing study — preliminary results from which appeared in late May 2016 — found a tiny increase in brain and heart tumors in male rats, it’s been strongly criticized: the statistical significance of that slight increase would disappear had the control rats in the study developed any tumors at all, which they inexplicably did not. (The breed used in the study usually develops tumors at rates of 2 percent to as high as 8 percent.) Meanwhile, huge studies of hundreds of thousands of people, such as in Denmark and Australia, have found no rise in brain tumors over the three decades during which we’ve begun to use cell phones.
Whether cell phone use harms babies, whether in the womb or after birth, is another open question. One study in pregnant mice suggesting it can has been criticized on very basic methodological grounds, and the so-called Babysafe Project warns mothers about the supposed harms from cell phones (but provides virtually no data to support its assertions).
Kheifets’s own work has linked pre-and postnatal cell phone use to what she calls “not very serious” emotional problems and hyperactivity as well as headaches in young children — yet her studies are careful to note those effects could be due to multiple other factors. A 2015 review by a European Commission panel of scientists found no evidence of harm from cell phones during pregnancy.
Indeed, cell phones could be changing us on a purely mental level, Kheifets says. Perhaps it’s “just the usage of this new technology changing our brains quite fast,” she says. “It might not necessarily be to do with the fields themselves, but just our interaction with this technology. Are we becoming faster and less accurate, for example, which seems to be the case?” If so, she asks, “what are the implications for society?”
Long-term studies are continuing to examine the issue. The Cosmos study is recruiting 250,000 adults from northern Europe, and will track their cell phone use for at least 25 years. The MOBI-Kids study is now recruiting children in Europe to examine the effects of cell phone use as they grow older.
In the meantime, Kheifets says she’s not trying to alarm mothers. “But since avoiding exposing yourself and the belly is so easy, why not do that? In a normal life, if there’s a small risk that you can avoid, why not?”
If you’re the cautious type, she suggests talking with a headset rather than holding a phone to your ear, and if you’re pregnant, keeping wireless phones away from your belly. And perhaps most importantly, for adults and children, since we tend to spend way too much time using our phones: limit phone time, period.
June 23, 2016
Christopher Nystuen, MD, MBA