Transcript for Health groups push for stricter FDA regulations on e-cigarette liquids

We turn to our "Gma" cover story this morning, new concerns about those teens using e-cigarettes. So many of them are using them, millions of them in fact. Health groups are asking why is the fda not doing more, could they be doing more, scared they could hit epidemic levels. Diane Macedo tracking this for us. Good morning. Good morning. It used to be relatively easy to bust kids for smoking but new vaping devices are making it harder and harder, producing little smell, less vapor. They don't even look like a cigarette and in some cases students are able to vape in the middle of class. Several health groups say the fda isn't doing enough and isn't moving fast enough. Reporter: It's the popular cigarette that doesn't look like a cigarette at all. Remove its cap and insert it into your Jewell. Each cartridge carries as much nicotine as an entire pack of cigarettes. Now the CDC says 2 million high school students are using products like Jewell for a quick rush. This month six organizations banded together sending this letter to the fda claiming manufacturers of e-cigarette products have produced new products at an alarming pace in total defines of law with no apparent concern for fda enforcement, including a host of new products introduced subsequent to the explosive growth in youth use of Jewell. We know that more and more products are hitting the market that are target is teens and kids. Reporter: Including banning flavored e-cigarette liquids which may appeal to teens and in mid September they'll launch a vaping prevention campaign targeting youths who vape or are open to trying it. The fda says online they're working hard to use their available tools to protect Americans from the harms of being addicted to tobacco products. According to one study published in the American journal of medicine, young adults who use e-cigarettes are more than four times as likely to start smoking tobacco cigarettes within 18 months compared to peers who don't vape. It's the flavoring, it's the sleek appearance of some of these products that we're really concerned about and we know that kids and teens who are using those products are more likely to use regular tobacco products in the future. Reporter: Jewell tells ABC news that their product is intended for current adult smokers only. We stand committed to working with those who want to keep Jewell out of the hands of young people. But high school freshman margarita told ABC news in June that flavoring enticed her to use Jewell. I just thought it was okay. Reporter: Jewell says the product's appearance is meant to help people quit. While they have fewer toxins than cigarettes, vaping can still expose people to cancer-causing chemicals and contain nicotine which can get both kids andaddictive. Thank you so much, Diane. We're going to go to our get

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