Button batteries are found mostly in hearing aids, but also in watches, clocks, cameras, key chains, remotes, greeting cards, shoes and lighted jewelry.
In other words, during the holidays, you may be seeing a lot of these shiny little objects.
Trouble is, so do small children, for whom button batteries can look like treats.
That's what her dad figures 20-month-old Shelby Thompson was thinking when she popped the button batteries for their jack-o'-lantern candles into her mouth on Halloween morning. To her 3-year-old sister, Bailey, Shelby's snack looked like a bad idea, and she alerted Dad.
Brock Thompson looked at Shelby and saw she was breathing fine. He scanned the table. Most of the batteries were still in the package, but one was on the floor — with teeth marks.
Shelby spit up. Instead of the familiar odor of sour milk, Thompson smelled the acrid stench of metal.
"I freaked out. I thought maybe it was melting her insides," Thompson recalled.
The Raymore, Mo., family raced to a Kansas City emergency room.
The battery had lodged in Shelby's esophagus. Endoscopic surgery removed it. Still, in four hours, one entire side of the disc battery had burned away, exposing its black surface.
Shelby is fine, now, Thompson said. But she'll be hearing about this baby story for years to come.
Nationwide, button batteries are ingested by some 3,000 people a year, according to the National Button Battery Ingestion Hotline in Washington.
Some of them are adults and older kids who, while installing a battery, hold it in their mouths and accidentally swallow
"Although 90 percent of those ingested batteries pass through without any harm, all of the incidents require a trip to the emergency room to get an X-ray to make sure it didn't get hung up in the esophagus or food canal," said Gary Wasserman, a pediatric medical toxicologist at Children's Mercy Hospitals and Clinics, where Shelby was treated.
Through a child's eyes, so many things look like something good to go in their mouths, he said.
"Mothballs could be marshmallows. Pine oil cleaners could be apple juice. Powder cleaners could be Parmesan cheese.... Pennies get stuck in throats. And those toys with magnets can cause some real problems."
Wasserman has even treated babies who tried drinking baby powder, thinking it's white like a bottle of milk, and then aspirated the fine dust into their lungs while the parent was busy changing their diaper.
"You have to stay ahead of the child's development to really try and see things the way they do," he said.
"Parents can forget that their child is developing enough to pull open a drawer, climb on a counter, even get into a visitor's purse and eat their medicines," Wasserman said.
Child-proofing your house can be as easy as crawling around, he said.
"Get down on all fours and look around. Think like a child and you'll see the dangers."