By Daniel Fink, M.D.
A new analysis on “the best kids’ headphones” by The Wirecutter, a product recommendations website owned by The New York Times, as reported in the New York Times science section, found that headphones marketed as “safe” for children’s hearing were louder than advertised. The Times’ article did not adequately reflect the extensive and thoughtful analysis by The Wirecutter’s reviewers, Lauren Dragan and Brent Butterworth. Their review deserves to be read (and reread) in its entirety, as it is without doubt the most complete and scientifically sound review about any noise topic that I have seen in the popular media.
The Wirecutter review mentions that two problems with headphones marketed as “safe for children”: (1) that the headphones are louder than they claim to be, and (2) that manufacturers are using an industrial-strength occupational noise exposure level as a safe noise level for children
. The review doesn’t emphasize the latter point enough.
I discuss the origin of the 85 decibel noise exposure standard in detail in an editorial in the January 2017 issue of The American Journal of Public Health. The 85 decibel volume level at issue was developed by the National Institute for Occupational Safety and Health (NIOSH) to protect workers’ hearing. It comes with strict time limits–an 8-hour day, 240 days a year, for a 40-year work career–and even then does not protect all workers from hearing loss. NIOSH discussed the difference between an occupational noise standard and a safe noise level for the public earlier this year in a blog post titled, “Understanding Noise Exposure Limits: Occupational vs. General Environmental Noise.” The NIOSH post makes it very clear that 85 decibels is not a safe noise level for the public, and it certainly is not safe for toddlers or children who may be listening to music or watching videos for more than 7 hours a day, every day. In addition, children, and especially teens, are exposed to other loud noise sources–action movies, sports event, etc.–so their total noise dose likely approaches dangerous levels.
Children’s ears may be more sensitive to noise than adult ears. First, there is no doubt that an 85 decibel headphone speaker is closer to a child’s eardrum because the external auditory canal is shorter in children than adults. (Noise follows the inverse square law, so the closer a noise source is to the ear the louder it is.) Second, it’s unlikely that children will limit their listening to just 240 days a year, on average they will live for almost 80 years, and in the course of their lifetimes they will undoubtedly be exposed to more noise, in gyms, parties, rock concerts, sports events, and the like. A child’s delicate ears have to last her a whole lifetime.
Studies of auditory acuity in so-called primitive populations show that significant hearing loss in old age is not inevitable. These studies are not available online, so I can’t provide links, but the classic studies were done in the 1960’s by Rosen and colleagues in the Mabaan population in the Sudan, and by Dickson and colleagues in the Kalahari Bushmen. Rosen found that the Mabaan could carry on a conversation at normal speech volumes while facing away from each other at a distance of 100 yards. Dickson wrote that the Bushmen could hear an airplane 70 miles away. As noted in The Wirecutter review, acute hearing was a matter of life or death for our primitive ancestors, either to find food or to avoid being a predator’s meal. The Rosen and Dickson studies suggest that hearing loss so commonly seen in the U.S. is likely not part of normal part of normal physiological aging, but rather is noise-induced hearing loss–i.e., the result of a lifetime’s exposure to excessive noise. If one starts listening to 85 decibel sound at age 3, hearing loss and hearing aids may be inevitable–and at an earlier age than in the past.
What can be done to protect children’s hearing from dangerous consumer products marketed to them? The federal agencies charged with protecting the public should do their jobs. The Federal Trade Commission should take enforcement action on the grounds of false advertising against vendors claiming that headphones with the 85 decibel volume limit are safe for children. They may be safer than headphones without a volume limit, but they are by no means safe, especially without recommendations for time limits on use. The Consumer Product Safety Commission should require warning labels on headphones, earbuds, and personal music players, stating “LOUD MUSIC CAUSES DEAFNESS!” The pediatric community should do more to educate parents about the dangers of noise for children. And parents must step up and demand truly safe products for their children or deny their children access to products that will destroy their hearing.
Dr. Fink is a leading noise activist based in the Los Angeles area. He serves on the board of the American Tinnitus Association, is the interim chair of Quiet Communities’s Health Advisory Council, and the founding chair of The Quiet Coalition, an organization of science, health, and legal professionals concerned about the impacts of noise on health, environment, learning, productivity, and quality of life in America.