1 00:00:02,040 --> 00:00:07,160 Speaker 1: Welcome to brain Stuff from how stuff Works. Hey, brain Stuff, 2 00:00:07,200 --> 00:00:10,320 Speaker 1: Lauren vocal bomb here. Even if you're not a tobacco user, 3 00:00:10,440 --> 00:00:13,680 Speaker 1: you're probably familiar with the cigarettes from their aggressive marketing 4 00:00:13,680 --> 00:00:18,200 Speaker 1: campaigns and popularity with former smokers. They're the electronic battery 5 00:00:18,200 --> 00:00:21,160 Speaker 1: powered devices that heat a fluid a k A. Liquid 6 00:00:21,280 --> 00:00:24,479 Speaker 1: or vape juice to create an aerosol that's inhaled in 7 00:00:24,560 --> 00:00:27,200 Speaker 1: place of the smoke that conventional cigarettes produced by burning 8 00:00:27,240 --> 00:00:31,240 Speaker 1: tobacco leaves. These fluids can contain any number of compounds 9 00:00:31,240 --> 00:00:34,720 Speaker 1: to create the puffs of aerosol, their flavors, and their effects, 10 00:00:34,960 --> 00:00:38,839 Speaker 1: including nicotine, the active ingredient in tobacco. E cigarettes are 11 00:00:38,960 --> 00:00:42,080 Speaker 1: rising in popularity, with ten point eight million adult users 12 00:00:42,120 --> 00:00:45,720 Speaker 1: in the US as of Part of the attraction maybe 13 00:00:45,720 --> 00:00:48,080 Speaker 1: that they're perceived as being less hazards to the health 14 00:00:48,159 --> 00:00:51,839 Speaker 1: than conventional smoking, since users don't receive the cancer causing 15 00:00:51,880 --> 00:00:55,480 Speaker 1: tar found in conventional cigarettes. Add to that the allure 16 00:00:55,520 --> 00:00:58,120 Speaker 1: of the sweet tasting flavorings available for addition to the 17 00:00:58,120 --> 00:01:00,760 Speaker 1: E liquid, and people such as US Food and Drug 18 00:01:00,760 --> 00:01:04,400 Speaker 1: Administration Commissioner Dr Scott Gottlieb worry it may be all 19 00:01:04,440 --> 00:01:08,479 Speaker 1: too appealing to youthful users, but that pleasant taste may 20 00:01:08,520 --> 00:01:11,560 Speaker 1: have a downside, researchers say. In a study published in 21 00:01:11,560 --> 00:01:15,760 Speaker 1: October eighteen in the journal Nicotine and Tobacco Research, scientists 22 00:01:15,800 --> 00:01:20,440 Speaker 1: from Duke and Yale Universities found that chemical flavorings for vanilla, cherry, citrus, 23 00:01:20,480 --> 00:01:24,080 Speaker 1: and cinnamon interacted with solvents such as propylene glycol and 24 00:01:24,160 --> 00:01:28,400 Speaker 1: glycerol in the E liquid, forming new compounds called acetols, 25 00:01:28,640 --> 00:01:32,200 Speaker 1: which can trigger irritation and inflammation when inhaled. According to 26 00:01:32,240 --> 00:01:35,520 Speaker 1: the Duke Medicine press release, the interaction occurs even before 27 00:01:35,640 --> 00:01:39,119 Speaker 1: the liquid is heated. We spoke with Hannah A. Wreath Repel, 28 00:01:39,280 --> 00:01:42,600 Speaker 1: a postdoctoral associate at the Yale Tobacco Center of Regulatory 29 00:01:42,600 --> 00:01:45,479 Speaker 1: Science and a co author of the study. He said, 30 00:01:45,760 --> 00:01:48,920 Speaker 1: we simply don't know what long term effects these compounds 31 00:01:48,960 --> 00:01:51,840 Speaker 1: and many other compounds in E cigrette liquid have on 32 00:01:51,880 --> 00:01:54,880 Speaker 1: the airways. Many of the additives to E liquids have 33 00:01:55,080 --> 00:01:58,520 Speaker 1: g R A S status, which means generally regarded as safe, 34 00:01:58,880 --> 00:02:00,919 Speaker 1: but that's based on in jest gin and on dermal 35 00:02:01,040 --> 00:02:04,160 Speaker 1: or skin exposure. There isn't much knowledge about what these 36 00:02:04,200 --> 00:02:07,160 Speaker 1: compounds might do in the airways and lungs, and that's 37 00:02:07,160 --> 00:02:10,600 Speaker 1: true for all vapors, young and old earth. Repel added 38 00:02:10,639 --> 00:02:13,840 Speaker 1: that scientists already know that further reactions take place during 39 00:02:13,880 --> 00:02:16,680 Speaker 1: the heating step of vaping. All of this means that 40 00:02:16,720 --> 00:02:19,480 Speaker 1: the initial list of ingredients for a liquid quote is 41 00:02:19,560 --> 00:02:22,800 Speaker 1: likely different from the final e liquid composition, which in 42 00:02:22,800 --> 00:02:25,160 Speaker 1: turn is different from what the user is exposed to 43 00:02:25,280 --> 00:02:28,920 Speaker 1: in the generated aerosol. How that might affect vapors bodies 44 00:02:29,000 --> 00:02:31,840 Speaker 1: isn't yet clear, but the researchers say that the irritant 45 00:02:31,840 --> 00:02:34,640 Speaker 1: compounds will persist in the body for some time after 46 00:02:34,720 --> 00:02:38,440 Speaker 1: a user vapes. Over time, that mild irritation could trigger 47 00:02:38,480 --> 00:02:41,639 Speaker 1: the immune system and create an inflammatory response in your body, 48 00:02:41,880 --> 00:02:44,360 Speaker 1: which isn't a good thing for anyone, but especially for 49 00:02:44,480 --> 00:02:47,919 Speaker 1: users with conditions like asthma and a breath. Repel notes 50 00:02:47,960 --> 00:02:50,960 Speaker 1: that the researchers have other concerns as well. He said, 51 00:02:51,320 --> 00:02:53,680 Speaker 1: if this reaction can take place that creates a more 52 00:02:53,720 --> 00:02:57,960 Speaker 1: irritating compound or possibly more toxic, what other reactions can 53 00:02:58,000 --> 00:03:01,000 Speaker 1: take place that might cause increased risk for users? We 54 00:03:01,080 --> 00:03:03,720 Speaker 1: simply don't know. I would add that long term effects 55 00:03:03,760 --> 00:03:06,000 Speaker 1: of vaping on the airways and the whole body are 56 00:03:06,080 --> 00:03:09,840 Speaker 1: generally unknown given how young these devices are, independent of 57 00:03:09,880 --> 00:03:12,880 Speaker 1: the final composition of the liquid, but the fact that 58 00:03:12,919 --> 00:03:16,600 Speaker 1: these more irritating compounds form is certainly not reassuring in 59 00:03:16,639 --> 00:03:20,720 Speaker 1: that regard. We also spoke via email with Robert Strongen, 60 00:03:20,919 --> 00:03:24,040 Speaker 1: a professor of organic chemistry at Portland State University who 61 00:03:24,080 --> 00:03:26,960 Speaker 1: was not connected with the Duke Yale study. He said 62 00:03:26,960 --> 00:03:29,400 Speaker 1: that just as users aren't aware of these new chemicals 63 00:03:29,400 --> 00:03:33,040 Speaker 1: being created an e liquid, scientists similarly don't know much 64 00:03:33,040 --> 00:03:36,200 Speaker 1: about the effect of those chemicals on the body. Quote, 65 00:03:36,480 --> 00:03:39,440 Speaker 1: we know very little or nothing about the flavoring additives 66 00:03:39,560 --> 00:03:41,680 Speaker 1: or even much about the solvents as far as their 67 00:03:41,720 --> 00:03:46,400 Speaker 1: inhalation toxicity, especially as chronically used in e cigarettes. A 68 00:03:46,480 --> 00:03:51,160 Speaker 1: chemical safer ingestion are not necessarily safe for inhalation inhaled 69 00:03:51,280 --> 00:03:55,160 Speaker 1: organic solvents and flavorings bypass processing by these stomach and 70 00:03:55,200 --> 00:03:58,480 Speaker 1: liver lung tissue is different. Just because we can eat 71 00:03:58,520 --> 00:04:01,280 Speaker 1: flavor molecules doesn't mean at all that it's okay to 72 00:04:01,320 --> 00:04:04,680 Speaker 1: inhale them. Earth Repel says that more research is needed 73 00:04:04,720 --> 00:04:07,440 Speaker 1: on the chemical changes in e liquids and what health 74 00:04:07,440 --> 00:04:10,480 Speaker 1: effects they may have, which will be a challenge seeing 75 00:04:10,480 --> 00:04:13,280 Speaker 1: as how, there are an estimated seven thousand flavors or 76 00:04:13,400 --> 00:04:16,480 Speaker 1: more on the market right now, and that market is growing. 77 00:04:21,640 --> 00:04:24,400 Speaker 1: Today's episode was written by Patrick J. Kaiger and produced 78 00:04:24,400 --> 00:04:26,479 Speaker 1: by Tyler Playing. For more on this and lots of 79 00:04:26,480 --> 00:04:29,159 Speaker 1: other health topics, visit our home planet, how stuff Works 80 00:04:29,200 --> 00:04:40,880 Speaker 1: dot com.