Sleep Machines May Damage Infant Hearing

“When closer to the crib, three machines produced sounds that exceeded both Canadian and American standards for long-term exposure to noise in industrial environments,” said Dr. Papsin. “Even at maximal distance, most were still above the 50 dBA suggested as the maximal limit in hospital newborn nurseries and neonatal intensive care units.”

The majority of the ISMs tested had volume controls. The researchers recommended that parents consider turning down the volume, placing the machine as far from the baby as possible, and using them for short periods of time only. The authors did not suggest that parents stop using them.

“Although we weren’t able to test children directly, there are a couple of interesting hypothetical predictions from our results,” said Dr. Papsin. “We know that exposure to industrial strength noise over time causes deafness. So, if we exceed these dose-response curves in an infant, it is possible that we may be inducing some hearing loss.”

Other Concerns

Dr. Papsin also noted that developing auditory systems in infants want information content from the environment. Research indicates that the type of auditory input shapes pathways over time. Thus, Dr. Papsin suggests that parents limit the use of white noise, opting instead for more varied sounds such as music or traffic.

However, he thinks otolaryngologists should use consumer interest to start a conversation between parents and physicians; specifically, he hopes they will discuss the concept of sound exposure as a dose of energy.

“When I was a kid, nobody put on suntan lotion, because we did not understand ionizing radiation,” he noted. “When medicine becomes aware of something, the world isn’t ending; it just means we should inform the public of potential risks. Now that we have the attention of parents, the dose of sound is a significant concern because the delicate cochlea we are trained to preserve and protect is threatened by sound throughout the environment.”

Comments from Others in the Field

This is a very important article from both societal and policy standpoints, according to David J. Eisenman, MD, associate professor of otorhinolaryngology-head and neck surgery and director of the Otology and Neurotology Program at the University of Maryland School of Medicine in Baltimore. He said that for more than a decade, there have been concerns regarding links between high noise levels from digital music players and hearing loss in teens. With the concerns raised about ISMs, he sees a risk for what he calls a “double whammy” from two common scenarios.