The danger posed to small children from swallowing batteries has been highlighted in a grim experiment carried out by the BBC.
Health correspondent Fergus Walsh used a slice of ham and a jug of water to show the damage small lithium batteries can do to human flesh.
Once water touches the battery, it causes the meat to bubble and burn.
"Eventually this would have burned its way right through the ham," Welsh says.
"Same thing with a child's throat."
Paediatric surgeon Joe Curry told the Guardian that the lining of the oesophagus can be damaged within 15 minutes of contact.
"We have seen rupture of the oesophagus within four hours."