Why are these batteries dangerous?
The danger occurs when these small batteries are put in a child (or adult's) mouth and swallowed. Most cause no problem and pass into the stomach. However, if they lodge in the oesophagus (food pipe), they can burn through its lining.
If lodged in the oesophagus, batteries must be removed immediately. In this location, if a battery remains lodged, it creates an electrical circuit, meaning the battery effectively can start to function and releases a caustic alkali substance.
This will cause severe burns and, in time, can result in the erosion through the wall of the oesophagus into the wind pipe. Marked injury can occur in as a short time as an hour.
Potentially, if the battery is facing a different direction when lodged, it can burn into the aorta. This is a major blood vessel, and can result in life-threatening bleeding.
There have also been incidents of children putting button batteries in their noses and ears as well, both which can also cause life-altering injuries.
Common incidents that occur involve young children swallowing their own hearing aid batteries or eating batteries lying loose, after they were removed from a device.