(Milt Savage/For The Washington Post)

Everyone knows, or should know, by now that tanning beds expose users to a lot of ultraviolet radiation, which can cause cancer. But according to a new study released Monday, indoor tanning also is responsible for an average of 3,234 injuries that result in visits to hospital emergency rooms each year.

That's nearly nine skin burns, fainting spells, eye injuries, lacerations, strains, sprains, bruises or dislocations every day that  could have been avoided, since, according to the Centers for Disease Control and Prevention, the practice also increases the risk of skin cancers, including melanoma. The CDC recommends against the use of tanning beds.

Gery P. Guy, a health economist who conducted the study for the CDC, said the true number of injuries is certainly greater. His data include only injuries treated in emergency rooms, but not those seen by private physicians, in urgent care facilities or treated at home.

Skin burns are the most common injury and women are more than four times as likely as men to get hurt, probably because they are, by far, the more common practitioners of "indoor tanning," according to the new research, published in the Journal of the American Medical Association. Younger adults, aged 18-34, sustain well more than half the injuries, again because they are the most frequent users of tanning beds. One in three women between the ages of 16 and 25 uses a tanning bed at least once a year.

The acute injuries also increase the risk of long-term problems, Guy said. Skin burns raise the risk of later skin cancer, and eye burns increase the chances a person may develop ocular melanoma, he said. The study is the first to gather data on acute injuries from tanning on a national basis.

If there is ray of good news, it's that the number of injuries declined sharply during the period examined by the researchers, 2003 to 2012, probably because the overall use of tanning beds declined. More than 6,000 acute injuries were registered in 2003, a total that had dropped to 2,000 in 2012.

Guy said people are getting the message about the dangers of tanning beds and 11 states have banned indoor tanning by people under 18.