Calls to poison control centres about young children's exposure to e-cigarettes have skyrocketed in recent years, new research shows.
And those kids who are exposed seem to suffer worse health effects than those exposed to traditional cigarettes, the study authors added.
The biggest threat with e-cigarettes appears to be the nicotine liquid inside the devices, the researchers said.
"If this were an infectious disease, it would be headlines across the country," said Dr Gary Smith, director of Nationwide Children's Hospital's Centre for Injury Research and Policy in Ohio. He noted that the number of e-cigarette exposures in kids jumped 1,500 percent from 2012 to 2015.
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"E-cigarettes and liquid nicotine can cause serious poisoning, and even death, among young children," he said. "Like other dangerous poisons, they should be kept out of sight and reach of children, preferably in a locked location."
The research, published online in the journal Paediatrics, follows last week's ban by the U.S. Food and Drug Administration on the sale of e-cigarettes to minors because of numerous health concerns in this vulnerable age group.
"This final rule is a foundational step that enables the FDA to regulate products young people were using at alarming rates, like e-cigarettes, cigars and hookah tobacco, which had gone largely unregulated," Mitch Zeller, director of the FDA Centre for Tobacco Products, said during a media briefing announcing the ban.
Danger to really young children
Smokers have flocked to e-cigs in recent years. The battery-powered devices heat up fluid until it becomes vapour, which is then inhaled. The fluid includes nicotine and other ingredients, such as flavours and chemicals.
Read: Concern about school kids using e-cigarettes
The new report suggests e-cigarettes, particularly the liquid nicotine, may pose the greatest harm to really young children.
The researchers analysed calls to the National Poison Data System about nicotine and tobacco products from January 2012 to April 2015. They focused on calls about kids under the age of 6.
According to the study, about 14 percent of calls were about exposure to e-cigarettes, compared to 60 percent about exposure to traditional cigarettes. In about 92 percent of the e-cig cases, the kids swallowed liquid nicotine.
"Information about the circumstances of the exposure were only available for about 5 percent of these cases," Smith said. "Among these, approximately 40 percent of the time, the liquid nicotine was stored within sight of the child."
In 2 percent of the e-cigarette cases, the kids suffered a moderate effect (71 cases) or a major effect (5 cases). There was also one death. There was no effect in almost half the cases and a minor effect in 22 percent. The effect wasn't clear in the other cases.
Read: Anti-tobacco advocate says electronic cigarettes are potential life-savers
Kids were admitted to health care facilities in 2 percent of cases, compared to 0.3 percent of cigarette exposure cases.
There are bigger poison risks
Gregory Conley, president of the American Vaping Association, a non-profit group dedicated to education about e-cigarettes and vapour products, said the concern about e-cigarettes is overblown.
The child who died, he said, consumed a homemade nicotine liquid concoction that's much stronger than retail versions that are easily available in the United States. And, he added, laundry detergent pods and prescription medications are bigger poisoning risks to kids.
He also pointed to statistics from the American Association of Poison Control Centres that report only 623 cases of exposure to e-cigarettes and liquid nicotine across all age groups from January to April of 2016. That's compared to about 3,000 in 2015 and almost 4,000 in 2014.
Conley believes the numbers have dropped because of publicity about the risk. A congressional law mandating childproof e-cigarette packages will take effect later this year and provide even more protection, he added.
Read: Better adjusted teen smokers prefer e-cigarettes
But Smith said more needs to be done.
"Other prevention steps include prohibiting the use of flavours, as was done for cigarettes since 2009, restricting the use of packaging and labelling attractive to children, ensuring that liquid nicotine compartments on e-cigarettes are child-resistant, and limiting the concentration and/or quantity of nicotine in refill products," he said.
So what should people who use e-cigarettes, called vapers, do if kids under 6 are nearby?
"Liquid nicotine needs to be treated like any other poison in your home," said report co-author Henry Spiller, director of the Central Ohio Poison Centre at Nationwide Children's Hospital in Columbus. "If you vape, store vaping supplies, especially refill containers, up, away and out of sight, preferably in a locked location. Don't leave them lying around on the coffee table, in the cup holder in your car, or in your purse."
Smith cautioned vapers to be aware that kids may be attracted by the smell and colours of e-cigarettes.
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