Using cotton buds to clean ears may seem harmless, but they have the potential to cause minor to severe injury to the ear, researchers have warned.

"The two biggest misconceptions I hear as an otolaryngologist are that the ear canals need to be cleaned in the home setting, and that cotton tip applicators should be used to clean them; both of those are incorrect," said Kris Jatana of the Nationwide Children's Hospital in Columbus, Ohio, US.

A study conducted by Nationwide Children's Hospital researchers found that over a 21-year period from 1990 through 2010, an estimated 263,000 children younger than 18 years of age were treated in US hospital emergency departments for cotton tip applicator-related ear injuries -- that is about 12,500 annually, or about 34 injuries every day.

"The ears canals are usually self-cleaning. Using cotton tip applicators to clean the ear canal not only pushes wax closer to the ear drum, but there is a significant risk of causing minor to severe injury to the ear," Jatana, who is senior author of the study published in the Journal of Pediatrics, said. 

The study found that the majority of injuries occurred as a result of using cotton tip applicators to clean the ears (73 per cent), playing with cotton tip applicators (10 per cent), or children falling when they have cotton tip applicators in their ear (nine per cent). 

The most common injuries were foreign body sensation, perforated ear drum and soft tissue injury. 

Data for this study were obtained from the National Electronic Injury Surveillance System (NEISS), which is operated by the US Consumer Product Safety Commission. 

The researchers said that in more serious cases, damage to the ear drum, hearing bones, or inner ear, can lead to dizziness, problems with balance, and irreversible hearing loss.

"These products may seem harmless, but this study shows how important it is that they not be used to clean ears," Jatana, who also serves as Associate Professor at the Ohio State University Wexner Medical Centre, said.