“For a quarter of a century now, the [mobile] industry has been orchestrating a global PR campaign aimed at misleading not only journalists, but also consumers and policymakers about the actual science concerning mobile phone radiation,” reported The Guardian in 2018.

This was reported in the wake of a landmark U.S. government study that concluded, “… there is clear evidence that radiation from mobile phones causes cancer, specifically, a heart tissue cancer in rats that is too rare to be explained as random occurrence,” The Guardian reported. Rats, according to scientists involved in the study, were used because of their biological similarities to humans.

Yet, no other major news organization in the U.S. or Europe reported the breakthrough finding, according to The Guardian. The authors of this article, “The Inconvenient Truth About Cancer and Mobile Phones,” likened the industry’s tactics to the big tobacco and oil industries that “deceive the public about the risks of smoking and climate change, respectively.” They wrote, “And like their tobacco and oil counterparts, wireless industry CEOs lied to the public even after their own scientists privately warned that their products could be dangerous, especially to children.”

Another study, conducted in the same year and published in the Journal of Public Health and Environment, aimed to investigate the rise of a brain tumor called glioblastoma multiforme (GBM) and found the use of mobile phones may be promoting it. Researchers analyzed 79,241 malignant brain tumor cases over 21 years and found cases of GBM in England went up from 1,250 per year to about 3,000 cases a year. Scientists at the helm of this research told The Telegraph, “…the increasing rate of tumors in the frontal temporal lobe raises the suspicion that mobile and cordless phone use may be promoting gliomas.” In the past, reported Hindustan Times, radiation from cell phones has been associated with two types of brain tumors: gliomas and acoustic neuromas.

Even the International Agency for Research on Cancer, a part of the World Health Organization, has said radiofrequency electromagnetic fields – related to the use of mobile phones – are carcinogenic.

There is also “more than sufficient evidence to show that radiation [from mobile phones] affects deep sleep,” concluded scientists of another study published by the Massachusetts Institute of Technology’s Progress in Electromagnetics Research Symposium. Their findings suggest that radiation from mobile phones causes sleep delays and reduced sleep, along with headaches and confusion. Use of handsets before bed or keeping mobile phones by the bedside caused people to take longer to reach the deeper stages of sleep, “interfering with the body’s ability to repair damage suffered during the day,” reported The Independent. “Failure to get enough sleep can lead to mood and personality changes, depression, lack of concentration and poor academic performance,” the article mentioned.

With enough evidence, but very little agreement, clear from how there’s very little on the internet on cancer+radiation+mobile phones, Dr. Sanjay Dudhat, senior consultant and surgical oncologist from Mumbai’s Nanavati Super Speciality Hospital, told Hindustan Times we can all at least follow one piece of advice: “Even though we don’t have a clear indication of cancer risk, it’s a scientific fact that cell phones emit radiation in a 3- to 4-foot radius.”

“For that reason alone, it’s wise not to sleep with your cellphone next to your head on the bed. Best to keep it on a table away from the bed,” he adds.

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Aside from radiation, sleeping with a mobile phone or charging it overnight in bed has also been linked to freak accidents. Take the most recent case for instance, in which a 14-year-old schoolgirl died after her charging smartphone exploded on her pillow while she slept. Her phone’s battery had exploded close to her head, and she was believed to have died from head injuries. Forensic experts confirmed that the mobile phone had exploded after overheating.

In 2017, the Hartford Home Fire Index, an insurance company, equated charging a phone in bed to leaving a candle burning, or the stove on. The New Hampshire Fire Department, on its Facebook page, wrote that the “… heat generated while charging a phone cannot dissipate, and the charger will become hotter and hotter.”

This phenomenon is called thermal runaway in the battery, explained Paul Shaw, head of fire investigation at Staffordshire fire rescue, to The Guardian. “[The battery] self-heats. It keeps going and going. You shouldn’t tuck phones under pillows or charge them on bedding.”

Adding that one must always use the charger that came with the phone, Shaw also said that all electrical devices must be charged on a work surface or wooden side table because the battery won’t generate enough heat on such surfaces.

Phil Buckle, the chief executive at Electrical Safety First, a charity organization, advised against charging devices through the night at all. “When you go to bed, switch everything off,” he told The Guardian.

While newer smartphones may be safer to charge overnight than previous models, it isn’t the most ideal way to replenish their batteries. Leaving a phone on charge overnight may cause its lithium-based battery to degrade due to the extreme heat. Lithium-ion batteries, which most smartphones now have, can’t withstand extreme heat or cold. “As [a phone] gets warmer, it charges faster. But since a battery can’t hold more than its capacity, after reaching a full charge the battery expends the excess power by giving it off as heat. Overnight charging becomes a problem when a battery has no way to reroute the incoming current after reaching its capacity,” states a website called Android Authority.

So far, all scientific evidence suggests common, phone-related nighttime habits could have consequences not only for you but also for your phone — if that’s what keeps you up at night.