Hearing loss has long been thought to be an unpleasant but inevitable side effect of aging. And aging is indeed the most common cause of hearing loss. But within the past year, two reports from the Centers for Disease Control and Prevention (CDC) have documented the startling degree to which noise—both in the workplace and elsewhere in our daily lives—contributes to hearing damage.
Findings published in the CDC's Feb. 7, 2017 Morbidity and Mortality Weekly Report (MMWR) demonstrated that 23.5 percent of people aged 20-69 who reported having good or excellent hearing had some degree of hearing loss, as measured by the presence of an audiometric notch (either unilateral or bilateral). While people exposed to loud noises at work were twice as likely to have hearing loss—nearly one-third of them had either a bilateral or unilateral notch—19.9 percent of those studied who reported no exposure to loud or very loud noise at work also had some degree of hearing loss.
It's important to note that this report was based on data from the 2011–2012 National Health and Nutrition Examination Survey (NHANES), said Anne Schuchat, MD, the CDC's acting director. “The NHANES survey allows us to not only rely on people's symptoms, or what they're aware of, but on documented testing. It's surprising that a sizeable population of young adults already had noise-induced hearing damage, and that they didn't work in noisy workplaces. Our emphasis in the past has largely been on reducing worker exposure to noise, but community or home noises are probably causing a lot of damage that is not evident.”
Although the new study did not pinpoint where participants were getting their noise exposure, Schuchat cited some examples of common community sources of hearing damage such as:
- Two hours of exposure to a leaf blower at 90 decibels can cause substantial hearing damage with repeated exposures over time
- 14 minutes at a sporting event with a noise level of 100 decibels can cause damage with repeated exposure; and
- Two minutes at a rock concert with levels of 110 decibels can cause damage, again with repeated exposure.