Newswise — In the mock-documentary "This is Spinal Tap," a member of the world's loudest band tried to secure the distinction by using amplifiers that went higher than the standard "10" setting on the volume control. He pointed out that his amps went to 11 " which, he said, was "one louder."

As parents do their holiday shopping this year, they may wonder if making the volume go to 11 was the inspiration behind many children's toys. From traditional noisemakers such as toy guns and musical instruments to talking dolls and animated stuffed animals, many toys are loud enough to cause permanent hearing damage, says a University of Michigan Health System expert.

"With the holidays approaching, parents need to be concerned and selective regarding the toys they purchase, in particular toys that produce some kind of a sound," says Paul R. Kileny, Ph.D., director of audiology and electrophysiology at the U-M Health System's Department of Otolaryngology. "These can be toys that are fairly high tech, or some very low-tech toys, such as whistles and accordions."

Kileny notes that children's hearing is particularly sensitive. While the inner ear is completely developed at birth and has the complete complement of hair cells, the ear canal is much smaller, and sounds entering the ear canal become louder because they develop in a smaller space.

That can translate into as much as a 20-decibel difference between adult and infant ears; thus, infant ears can be damaged more easily than adults' hearing. In addition, children tend to hold toys or games closer to their ears because of the short reach of their arms. Dolls and stuffed animals are often held directly up to the ear-region.

"When you make a judgment about a toy or a game, about whether to buy it or not, you really have to hold it up close to your ear," Kileny says. "If a toy sounds loud to an adult, it'll sound much louder to a child."

In general, Kileny says, it is best if toys do not exceed 80 to 85 decibels (the measure of the intensity of a sound). A normal conversation is about 60 decibels, lawnmowers and shop tools run at 90 decibels or so, a chainsaw at 100, a rock concert at 115, and a jet engine at 120 or higher.

Following a recent day in which he shopped in a toy store, Kileny tested the decibel output of numerous toys, including musical instruments, dolls, MP3 and CD players, and more. He found that many of the toys exceeded the 80-85 level at which it is safe for children to be exposed to the sound for extended periods of time.

"There are some toys and games that produce sounds as loud as a jet plane taking off," Kileny says. "That amount of output can cause immediate and permanent hearing loss."

Some musical instruments and music players designed specifically for children ages 3 to 5 can be excessively loud, he notes. An MP3 player marketed to toddlers, for instance, measured in at a peak of 120 decibels. Computer games often exceed 110 decibels. Musical instruments can peak at those levels as well.

In some instances, though, toy manufacturers seem to be taking notice of the need to make quieter toys. Some toys now come with controls parents can set to limit the noise output, for example. Kileny hopes more toy manufacturers will follow suit in the future.

The hearing damage caused by toys may not manifest itself until later in life, either in the teenage years or even beyond that, when a person experiences early hearing loss. A recent Zogby International poll commissioned by the American Speech-Language-Hearing Association found that more than half of high school-aged people who responded to the survey reported at least temporary signs and symptoms that may be associated with hearing loss, Kileny says " damage that for some of them likely began when they were very young.

Kileny notes that in addition to hearing screens that are performed on newborns, parents also can ask their doctors about possible changes in their children's hearing. "If you've made observations that your child doesn't hear as well as your other children or friends, or that he or she doesn't hear as well as six months ago," Kileny advises, "bring this to your physician's attention and request referral to a licensed audiologist to determine the hearing status."

Information about noisy toys and hearing loss:"¢ Many toys for toddlers exceed safe sound levels, with some peaking at decibel levels as high as a jet engine taking off.

"¢ Noisy toys can come in many varieties " a toy as simple as a whistle or complex as an MP3 player, fire engines and dolls, cap guns and musical instruments.

"¢ Children's ears are more susceptible to the effects of loud noises than are adults' ears. Additionally, children often hold toys and games close to their ears. Adults should listen to a toy close to their ear to hear if it sounds too loud before they purchase it.

"¢ If children already own noisy toys, parents can consider taking out the batteries.

"¢ Hearing loss from loud toys is permanent.

For more information, visit these Web sites: UMHS Health Topics A-Z: Childhood hearing losshttp://www.med.umich.edu/1libr/pa/pa_hearing_hhg.htm

National Institute on Deafness and Other Communicable Disorders: Noise-induced hearing loss http://www.nidcd.nih.gov/health/hearing/noise.asp

American Academy of Family Physicians: How to prevent noise-induced hearing loss www.aafp.org/afp/20000501/2759ph.html

KidsHealth: Choosing safe toyshttp://www.kidshealth.org/parent/growth/learning/safe_toys.html

American Speech-Language-Hearing Association: Noisy toys, dangerous play http://www.asha.org/public/hearing/disorders/noisy_toys.htm

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