Michael Greger M.D. FACLM asks in his NutritionFacts.org blog, “What impact might cell phone and Bluetooth radiation have on the inner ear?”
“Given the huge number of mobile [cell] phone users at present days, even simple adverse health effects could have major implications.” “The major concern about cell phones is that they are usually held close to the head, resulting in significant exposure to the brain and other tissues on the side of the head where the phone is usually placed.” Other tissues? Yes, such as your inner ear, the organ most frequently and directly exposed to cell phone radiation. What about possible adverse effects on hearing? In fact, the ear canal “may provide a natural route by which emitted radiofrequency radiations may reach the peripheral and central nervous system,” going deeper into your skull.
A first natural question to ask might be: Do long-term cell phone users have a worse hearing? Apparently, they do. Cell phone users were found to have detectable hearing loss, though not enough to be noticeable, suggesting long-term cell phone use might damage the inner ear. The damage was bilateral, or detectable in both ears, which may be more consistent with a radiation effect than simply a constant loud-noise-in-one-ear effect.
Now, this was comparing users to complete nonusers. As you can see at 1:20 in my video The Effect of Cell Phones and Bluetooth on Nerve Function, if you compare heavy cell phone users to light users, there appears to be a dose-response: the longer the duration of daily cell phone use (up to four or five hours in this study), the more the hearing loss. Researchers found heavy-use participants had a higher sound threshold before they could hear the hearing test tone and concluded this “clearly revealed hazardous effects of mobile phone use on auditory function.” They went on to say that “based on the study, it is recommended to use mobile [cell] phones very judiciously,” as there does not appear to be any difference between non-users and those who just used it 10 to 20 minutes a day. Two hours a day, however, did appear to be associated with a certain amount of hearing loss, blamed on “long-term exposure to electromagnetic (EM) field generated by cellular phones.” But, to make a claim like that, you can’t just use observational studies like these. You need to put it to the test.