A study published in Occupational and Environmental Medicine claims evidence that mobile phones cause tinnitus, persistent ringing in the ears.
The premise is that microwave radiation (or "radio waves" as we sometimes call them) cause a calcium imbalance, or something like that – the study doesn't present evidence of the process, but it does find 33 people who got tinnitus on the same side of their head as they used a mobile phone.
The study of 100 sufferers also found 25 people who got tinnitus in the opposite ear, but statistical analysis comparing the sample to 100 random outpatients would seem to indicate that those who used a mobile phone for more than four years did have a significantly increased chance of developing the condition.
The sample size is terribly small of course, and even the study's authors admit that the increasing rate of tinnitus could be down to better diagnosis, or (more worryingly) that those who use mobile phones a lot could also be Walkman users. We'd speculate that they might be frequent flyers too – air travel always seeming to make the ears suffer.
That leaves aside the increased tension of being on the phone all the time, not to mention the flattened ear and constantly cocked head (though the study does mention "cranio-cervical manipulations of the head, neck or extremities" as a possible cause).
Either way, this tiny study does throw up evidence of a small increase in risk even if the suggested explanation is little more than speculation. That's not enough to stop anyone using a mobile phone, but it should be enough to prompt further research.
Abstract
Objectives The mechanisms that produce tinnitus are not fully understood. While tinnitus can be associated with diseases and disorders of the ear, retrocochlear diseases and vascular pathologies, there are few known risk factors for tinnitus apart from these conditions. There is anecdotal evidence of an link between mobile phone use and tinnitus, but so far there have been no systematic investigations into this possible association.
Methods
100 consecutive patients presenting with tinnitus were enrolled in an individually matched case–control study. For each case a control subject was randomly selected from visiting outpatients matched for sex and age. The patient's history was obtained and clinical examinations were conducted to exclude patients with known underlying causes of tinnitus. Mobile phone use was assessed based on the Interphone Study protocol. ORs were computed by conditional logistic regression with years of education and living in an urban area as covariates.
Results
Mobile phone use up to the index date (onset of tinnitus) on the same side as the tinnitus did not have significantly elevated ORs for regular use and intensity or for cumulative hours of use. The risk estimate was significantly elevated for prolonged use (≥4 years) of a mobile phone (OR 1.95; CI 1.00 to 3.80).
Conclusions Mobile phone use should be included in future investigations as a potential risk factor for developing tinnitus.
