After asking a group of college students to listen to the rock song "Summer of 69" by Brian Adams on their iPods or other personal music players,  researchers at the University of Southern Mississippi in Hattiesburg checked the volume of the devices and discovered that about 55 percent of current college students could eventually suffer permanent hearing loss.

“Fifty-five percent set their devices to 'very loud' levels [greater than 85 decibels],” the researchers said in a paper to be presented at an upcoming meeting of the Acoustical Society of America. Twenty-six percent set their devices to "loud" levels between 70 and 85 decibels, and only 19 percent listened at moderate levels below 70 decibels.

"No subjects had significant hearing loss," the researchers said of the 31 students tested, "but it should be noted that these subjects had owned [personal music players] less than three years and have not, thus far, had enough exposure to cause permanent hearing loss."

The researchers noted that anything above 85 decibels over 8 hours is considered hazardous.

When students were allowed to pick their own music, the rock music was played as loud as 107 decibels, while rap music hit 100 decibels.  The highest average volumes, however, were used by students listening to pop [88 decibels] and country [89 decibels] music.

Jim Dawson reports for Inside Science News Service.