It's likely that many more people swallow wire bristles than those who show up in the ER, Grand noted.
"We don't know how many people ingest these things and have no symptoms. My guess is that's much more common than the injuries," he said.
Dr. Joel Levine, a professor of gastroenterology at the University of Connecticut, said he's not surprised that a wire bristle might get stuck in a bite of steak or a burger, but the risk of someone's being injured from their grill brush is probably a "low-probability event."
"Actually, the risks from what you are cooking on the grill likely outweigh the brush bristles," Levine said. "High amounts of grilled meats have been long known as a cancer risk."
The CPSC advises consumers to inspect their grills before firing them up, keeping an eye out for stray pieces of metal that could get stuck in food. Grand said barbecuers should replace worn-out grill brushes or consider using cleaning tools that don't use wire bristles.