Aluminum can stay-tabs still pose swallowing risk for children

Evidence from x-ray exams suggests that tabs used to open aluminum beverage cans pose a swallowing risk to children, according to a study presented Monday at the 2009 RSNA meeting.

Cans were redesigned in the mid-1970s to reduce the risk of accidental swallowing of the tabs. However, the study found 19 children had ingested tabs between 1993 and 2009. The finding is particularly troubling to radiologists because aluminum is extremely hard to see on x-rays compared with other metals, said lead investigator Dr. Lane F. Donnelly, chief of radiology at Cincinnati Children's Hospital Medical Center.

Prior to the 1980s, beverage cans were opened via removable pull-tabs. However a 1975 study in the Journal of the American Medical Association examined two cases of accidental swallowing and one case of aspiration of pull-tabs that had been dropped back into the can. Since then, beverage manufacturers have constructed pull-tabs that remain attached, albeit loosely, to the original can.

"If you fiddle with these stay-tabs, you can easily pull them off," Donnelly said.

Of the 19 accidental ingestions identified in the study, only four (21%) were visible on x-rays. In these four cases, the tab was located in the stomach. Radiologists can easily spot swallowed foreign bodies like pennies because they are made of copper and zinc. But aluminum, a much lighter metal, can be nearly invisible on x-rays, Donnelly said.

"Not seeing the tab on the x-ray does not mean it was not swallowed," he said.

None of the 19 cases required surgery. However, tabs have jagged edges that can lacerate or embed themselves in the bowel or small intestine. Interestingly, only four of the subjects were children younger than five years old.

"It is unusual that the majority [of] cases occurred among teenagers, since foreign-body ingestion typically occurs in infants and toddlers," Donnelly said.

Study findings might demonstrate an overall safety hazard with stay-tabs. Therefore, beverage cans should be redesigned to make tabs less easy to remove by children, Donnelly said.