A recent study is calling the safety of e-cigarettes into question.
Researchers at Harvard said a very dangerous chemical, diacetyl, is found in the flavoring liquid in most e-cigarettes.
Their study found more than 75 percent of flavored e-cigarettes they tested contain diacetyl, which has been linked to a debilitating respiratory disease known as "popcorn lung."
The disorder leads to excessive coughing and shortness of breath.
While the study finds most e-cigarette liquids tested have this chemical in it, one local vape shop owner said the key word is "most."
He said none of their liquids, which they create on their own, contain the dangerous diacetyl.
Ryan Madtes said he quit smoking five years ago and turned to e-cigarettes.
"I can feel a huge difference in my breathing, in my lung pattern. I can run around with my daughter in the park and not get winded," he said.
Many vapers say e-cigarettes are a safer alternative to cigarettes, and vaping's popularity is on the rise.
The chemical researchers are finding in the e-cigarette liquids, diacetyl, is a preservative found in many foods, and it's safe to eat, but not to breathe in.
That's why Madtes, who also manages the Vape Store on Del Prado Blvd, said they don't carry e-liquids with diacetyl.
"We are 100 percent diacetyl-free in all of our house juices. One hundred and ten percent safe e-liquids from the U.S.," Madtes told Four in Your Corner's Lisa Greenberg.
He also said they come up with all of their flavor recipes.
"We have a big part in the chemical makeup of it. We know what we're putting in there, and we know what flavorings are safe to use and are diacetyl free," Madtes said.
While 47 of the 51 e-cigarette liquids tested in the study had diacetyl or hazardous chemicals like it, Madtes said you won't find those in their hundreds of house recipes.
He said a heavy vaper goes through about 20 to 30 milliliters of liquid a day, and in order to feel the effects of popcorn lung, an e-cigarette user would have to vape more than one hundred if the liquid has diacetyl in it.
Madtes also said cigarettes have more of the chemical than e-cigs do.
