Speaker 1: Welcome to brain Stuff from how stuff Works. Hey, brain Stuff,
Speaker 1: Lauren vocal bomb here. Even if you're not a tobacco user,
Speaker 1: you're probably familiar with the cigarettes from their aggressive marketing
Speaker 1: campaigns and popularity with former smokers. They're the electronic battery
Speaker 1: powered devices that heat a fluid a k A. Liquid
Speaker 1: or vape juice to create an aerosol that's inhaled in
Speaker 1: place of the smoke that conventional cigarettes produced by burning
Speaker 1: tobacco leaves. These fluids can contain any number of compounds
Speaker 1: to create the puffs of aerosol, their flavors, and their effects,
Speaker 1: including nicotine, the active ingredient in tobacco. E cigarettes are
Speaker 1: rising in popularity, with ten point eight million adult users
Speaker 1: in the US as of Part of the attraction maybe
Speaker 1: that they're perceived as being less hazards to the health
Speaker 1: than conventional smoking, since users don't receive the cancer causing
Speaker 1: tar found in conventional cigarettes. Add to that the allure
Speaker 1: of the sweet tasting flavorings available for addition to the
Speaker 1: E liquid, and people such as US Food and Drug
Speaker 1: Administration Commissioner Dr Scott Gottlieb worry it may be all
Speaker 1: too appealing to youthful users, but that pleasant taste may
Speaker 1: have a downside, researchers say. In a study published in
Speaker 1: October eighteen in the journal Nicotine and Tobacco Research, scientists
Speaker 1: from Duke and Yale Universities found that chemical flavorings for vanilla, cherry, citrus,
Speaker 1: and cinnamon interacted with solvents such as propylene glycol and
Speaker 1: glycerol in the E liquid, forming new compounds called acetols,
Speaker 1: which can trigger irritation and inflammation when inhaled. According to
Speaker 1: the Duke Medicine press release, the interaction occurs even before
Speaker 1: the liquid is heated. We spoke with Hannah A. Wreath Repel,
Speaker 1: a postdoctoral associate at the Yale Tobacco Center of Regulatory
Speaker 1: Science and a co author of the study. He said,
Speaker 1: we simply don't know what long term effects these compounds
Speaker 1: and many other compounds in E cigrette liquid have on
Speaker 1: the airways. Many of the additives to E liquids have
Speaker 1: g R A S status, which means generally regarded as safe,
Speaker 1: but that's based on in jest gin and on dermal
Speaker 1: or skin exposure. There isn't much knowledge about what these
Speaker 1: compounds might do in the airways and lungs, and that's
Speaker 1: true for all vapors, young and old earth. Repel added
Speaker 1: that scientists already know that further reactions take place during
Speaker 1: the heating step of vaping. All of this means that
Speaker 1: the initial list of ingredients for a liquid quote is
Speaker 1: likely different from the final e liquid composition, which in
Speaker 1: turn is different from what the user is exposed to
Speaker 1: in the generated aerosol. How that might affect vapors bodies
Speaker 1: isn't yet clear, but the researchers say that the irritant
Speaker 1: compounds will persist in the body for some time after
Speaker 1: a user vapes. Over time, that mild irritation could trigger
Speaker 1: the immune system and create an inflammatory response in your body,
Speaker 1: which isn't a good thing for anyone, but especially for
Speaker 1: users with conditions like asthma and a breath. Repel notes
Speaker 1: that the researchers have other concerns as well. He said,
Speaker 1: if this reaction can take place that creates a more
Speaker 1: irritating compound or possibly more toxic, what other reactions can
Speaker 1: take place that might cause increased risk for users? We
Speaker 1: simply don't know. I would add that long term effects
Speaker 1: of vaping on the airways and the whole body are
Speaker 1: generally unknown given how young these devices are, independent of
Speaker 1: the final composition of the liquid, but the fact that
Speaker 1: these more irritating compounds form is certainly not reassuring in
Speaker 1: that regard. We also spoke via email with Robert Strongen,
Speaker 1: a professor of organic chemistry at Portland State University who
Speaker 1: was not connected with the Duke Yale study. He said
Speaker 1: that just as users aren't aware of these new chemicals
Speaker 1: being created an e liquid, scientists similarly don't know much
Speaker 1: about the effect of those chemicals on the body. Quote,
Speaker 1: we know very little or nothing about the flavoring additives
Speaker 1: or even much about the solvents as far as their
Speaker 1: inhalation toxicity, especially as chronically used in e cigarettes. A
Speaker 1: chemical safer ingestion are not necessarily safe for inhalation inhaled
Speaker 1: organic solvents and flavorings bypass processing by these stomach and
Speaker 1: liver lung tissue is different. Just because we can eat
Speaker 1: flavor molecules doesn't mean at all that it's okay to
Speaker 1: inhale them. Earth Repel says that more research is needed
Speaker 1: on the chemical changes in e liquids and what health
Speaker 1: effects they may have, which will be a challenge seeing
Speaker 1: as how, there are an estimated seven thousand flavors or
Speaker 1: more on the market right now, and that market is growing.
Speaker 1: Today's episode was written by Patrick J. Kaiger and produced
Speaker 1: by Tyler Playing. For more on this and lots of
Speaker 1: other health topics, visit our home planet, how stuff Works
Speaker 1: dot com.