Toronto, Jan 31 (IANS) If you thought bursting balloons at a birthday party is plain fun, think again! Researchers have found that popping balloons can be louder than shotgun blasts -- and can lead to permanent hearing loss.

"We are not saying don't play with balloons and don't have fun, just try to guard against popping them. Hearing loss is insidious -- every loud noise that occurs has a potential lifelong impact," said one of the researchers Bill Hodgetts from University of Alberta in Canada.

The researchers measured the noise generated by bursting balloons and were startled to find that the impact, at its highest level, was comparable to a high-powered shotgun going off next to someone's ear.

Wearing ear protection and using a high-pressure microphone and a preamplifier, the researchers measured the noise effects by busting balloons three different ways: popping them with a pin, blowing them up until they ruptured and crushing them until they burst.

The loudest bang was made by the ruptured balloon at almost 168 decibels, four decibels louder than a 12-gauge shotgun, according to the study published in the journal Canadian Audiologist.

The Canadian Centre for Occupational Health and Safety recommends that the maximum impulse level any Canadian should experience should not exceed 140 decibels. Even one exposure could be considered potentially unsafe to hearing for both children and adults.

"It's amazing how loud the balloons are," Dylan Scott, also of University of Alberta, noted.

"Nobody would let their child shoot something that loud without hearing protection, but balloons don't cross people's minds," Scott pointed out.

The results for the other two methods were slightly lower, but still a concern, he said.