Although they are often thought of as toys, BB guns annually injure as many as 21,000 Americans, many of them children, according to a study in the November issue of Pediatrics.

Nonpowder guns kill an average of four Americans yearly, and from 1990 to 2000, there were 39 such deaths -- 32 of children younger than 15, the study found.

Nationally, an estimated 21,840 injuries related to nonpowder guns were treated in emergency departments in 2000 -- most in children ages 5 to 14, according to a report prepared by the American Academy of Pediatrics' Committee on Injury, Violence and Poison Prevention.

"They're being given as toys without recognition that there may be a serious injury risk," said the report's author, Dr. Danielle Laraque, a New York pediatrician.

The report covers all nonpowder guns, also called air guns, not just the popular BB guns. Air guns have been used since the 16th century in warfare and to kill game as large as deer. Besides metal projectiles, air guns can launch gelatin balls filled with paint, such as those used in war games.

The U.S. Consumer Product Safety Commission (CPSC) estimates that there are approximately 3.2 million nonpowder guns sold yearly. Nonpowder guns are sold in many department stores, including toy stores.

According to data from the Centers for Disease Control and Prevention (CDC) and the CPSC, there were 21,840 nonpowder gunrelated injuries treated in emergency departments. Of these, 49% occurred in children 5 to 14 years of age and 33% in those 15 to 24 years of age.

Approximately 12% of injuries were to the eye; 24% were to the head and neck, 63% were to extremities; and 1% were to other body areas. With the exception of the age group of 0 to 4 years, most victims were males.

The report found a correlation between the increasing popularity of paintballs used in war games and an increase in eye injuries and noted that the visual outcome for many of these injuries is poor. Many of the injuries have occurred even with eye-protective devices, though none to players properly wearing an eye protector that meets current U.S. safety standards.

There have been no reported deaths directly related to paintballs, but the CPSC issued a warning on March 24, 2004, because of its investigation of 2 deaths caused by carbon dioxide canisters flying off paintball guns.