Whether it's buttons or coins, small children often mistakenly swallow "foreign bodies".
Generally harmless, these tend to pass through the system without the child requiring medical attention.
Now a study has found that bizarrely, the number of children needing hospital care for swallowing a magnet has risen five-fold over five years.
Medics from four hospitals in South-East England have reported a five-fold increase in the number of children who swallowed magnets between 2016 and 2020.
While swallowing a single magnet may be relatively harmless, ingesting more than one could cause them to become attracted to each other in the intestine, potentially resulting in tissue death or even a hole forming all the way through the organ's wall.
Although it is still unexplained why these incidents are on the rise, the medics have warned that magnets are often found in "household toys". UK legislation states such toys must be sold with a warning, but "most manufacturers do not display these".
The Quadri-South East Paediatric Surgeons (QuadriSEPS) Group – made up of the Evelina London Children's Hospital, King's College Hospital, St George's University Hospitals and the Royal Alexandra Children's Hospital – have all reported an increase in magnet ingestion.
From January 2016 to December 2020, the group treated 251 children who were admitted after swallowing a foreign body.
Coins had been swallowed in more than a third (37%) of cases, followed by magnets (21%) and button batteries (17%).
Ingestion of any foreign body steadily rose by 56% over the five years.
"Worryingly, there was a five-fold increase in the incidence of magnet ingestion during the same time period," the group wrote in the journal Archives of Disease in Childhood.
Magnetic toys are normally only recommended for children aged 14 or over. The QuadriSEPS group treated patients ranging from four months to 16 years old, with seven being the average age.
Watch: What happens when a child swallows a button battery
Only one of the 42 (2.4%) button battery cases required surgery. Experts have warned these cylindrical objects may be particularly easy for a child to swallow, potentially causing severe internal burns.
More than two in five (42%) of the youngsters who swallowed a magnet had to go under the knife.
Overall, 10 of the 251 (4%) foreign ingestion cases endured surgical complications after the offending object was removed.
Magnets were involved in eight (80%) of these complications, of which four were classed as grade III, "requiring surgical, endoscopic or radiological intervention".
"As a regional network of paediatric surgeons, we are extremely concerned with the recent rise in cases we have seen with foreign body ingestion and, in particular, magnets," wrote the medics.
"We recommend a strong public health campaign to increase awareness of the dangers of small, powerful magnets, especially those intended for toys, and to work with manufacturers in clearly warning purchasers of the dangers for children."
How to prevent swallowing accidents
To help prevent a child swallowing a foreign object, experts recommend parents only buy toys that are suitable for their age.
Parents should also get down on their hands and knees to see a room from a child's perspective, removing any potential hazards.
Batteries should be stored out of reach, and correctly recycled or disposed of when out of charge.
The compartments of toys that contain batteries or magnets should always be closed properly, with a child being supervised while playing.
If anyone is known to have swallowed something dangerous or shows signs of serious ill-health, call 999 immediately.
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