More and more children are being poisoned by drinking the liquid nicotine cartridges that go inside the e-cigarettes.
The liquid that fuels the e-cigarettes is extremely concentrated.
So even a little bit can be very harmful and even fatal for children who drink it by accident.
Trauma Nurse Jason Martin at Cox Hospital is warning parents about a new danger.
"It is a poison," he said.
Liquid nicotine, the fluid that fuels e-cigarettes.
It's meant to be converted into a vapor and it can be deadly if ingested as liquid.
"If you get a child who's 25 or 30 pounds, one swallow of it could be lethal. So we want to make sure to keep this out of kids hands," he said.
But more and more children are getting poisoned and ending up in the emergency room.
In 2013 nearly 400 cases were reported nation-wide.
That's up 300 percent from the 2012 reports.
Emergency Rooms in Springfield have not seen these cases yet, but there have already been cases statewide this year.
"Just for the first couple of months of 2014 we've seen 14 cases," Missouri Poison Center Director Julie Weber said.
She is urging parents to keep these cartridges away from little ones.
"Get products up high in locked cabinets and out of the reach and out of the sight of children," she said.
"They don't have child proof tops on them so they're actually pretty easily accessible for kids," Martin said.
Until tighter regulations are placed on the packaging for e-cig refills, he said it's up to the parents to be careful.
The regulations on e-cigarette refill cartridges are much more strict in Europe than in the U.S.
The FDA and lawmakers would like restrictions on concentration of the nicotine and better child-proof packaging.
U.S. Senator Mark Pryor of Arkansas is one of those lawmakers that wants the Food and Drug Administration to better protect people from liquid nicotine.
Pryor sent a letter to the agency, requesting information about how the FDA oversees the product.
The number to contact the Missouri Poison Center if you would like more information is 800-222-1222.
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