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PROPYLENE GLYCOL AND ELECTRONIC CIGARETTES

The transparent truth. Tobacco or Electronic Cigarettes?
You Decide.

What is propylene glycol?

Propylene glycol is used as a humectant which means it maintains moisture levels in food products, cosmetics and tobacco products. Humectants are what make hair conditioning products work as well as create the moisturizing effects of many common cosmetics and consumer products we take for granted such as: make up, mascara, hand creams, body lotions as well as shaving creams, shampoos and soaps. Additionally, propylene glycol is used as a solvent to enhance the ability of artificial flavorings to remain suspended in solution in products such as toothpaste and mouthwash.

How is it made?
Propylene glycol is a petroleum-based product, in other words it is derived from crude oil. The crude oil is processed into a substance called Naptha which is in turn created into an intermediate substance called Propylene Oxide. This substance is then turned into propylene glycol. A glycol is simply a form of an alcohol molecule. It is this molecular transformation which makes propylene glycol function as a moisturizing agent.

What are propylene glycols applications?

Propylene glycol is used:

1.    As a solvent in many pharmaceuticals, including oral, injectable and topical formulations.

2.    As a humectant food additive, labeled as E number E1520

3.    As a moisturizer in medicines, cosmetics, food, toothpaste, mouth wash, and tobacco products

4.    As a carrier in fragrance oils

5.    As an ingredient in massage oils

6.    In hand sanitizers, antibacterial lotions, and saline solutions such as eye drops

7.    In smoke machines to make artificial smoke or fog

8.    In electronic cigarettes, it is used to deliver vaporized nicotine (where legally available)

9.    As a solvent for food colors and flavorings

10. As an ingredient, along with wax and gelatin, in the production of paintballs

11. As a moisture stabilizer (humectant) for snus (Swedish style snuff).

12. As a cooling agent for beer and wine glycol jacketed fermentation tanks

13. As a less-toxic antifreeze

14. To regulate humidity in a cigar humidor

15. As an additive to pipe tobacco and regular cigarette tobacco to prevent dehydration.

16. As the main ingredient in deodorant sticks.


How much propylene glycol am I exposed to on a daily basis?

A lot, actually. If you use toothpaste, mouthwash, makeup, mascara, soap, shampoo, hand cream, eye drops, shaving cream, eat cake, brownies, donuts, cake frosting, smoke cigarettes, you are already exposed to propylene glycol on a daily basis. It is unknown exactly how much is too much.

However, the FDA states that propylene glycol meets the
GRAS standard aka Generally Recognized As Safe.
http://www.fda.gov/Food/FoodIngredientsPackaging/GenerallyRecognizedasSafeGRAS/GRASSubstancesSCOGSDatabase/ucm084142.htm

The research on propylene glycol use and consumption is extensive in animals and humans. For animals, the basic rate is around 9mg per liter per kilogram (2.2 lbs) of body weight per day on average. However, what happens when that level is exceeded are things like skin irritation, nausea which may result at much higher dosages. That said, if one considers just how many consumer products rely on propylene glycol, it is hard to imagine that the additional consumption in the form of electronic cigarettes would do anything to materially affect toxicity above and beyond what is seen naturally occurring across human populations on a daily basis. Also, considering that people have a differing range of propylene glycol exposure from various food and cosmetic products and have different body weights, getting an exact dosage amount would prove challenging. That said, the amounts that electronic cigarettes pose to add to the overall average exposure amount could be classified as negligible.

According to the following research studies, Gaunt, IF, Carpanini, FMB, Grasso, P and Lansdown, ABG, Long-term toxicity of propylene glycol in rats, Food and Cosmetics Toxicology, Apr. 1972, 10(2), pages 151 162 and National Library of Medicine;.Propylene glycol Human Toxicity Excerpts: CAS Registry Number: 57-55-6 (1,2-Propylene Glycol). Selected toxicity information from HSDB. 2005

The oral toxicity of propylene glycol is extremely low, and large amounts are required to instigate the dangerous effects. The potential for long-term toxicity is also very low. In one study, rats were given feed with as much as 5% PG over a period of 104 weeks and showed no apparent ill effects. Due to propylene glycols low chronic oral toxicity, propylene glycol is generally recognized as safe (GRAS) for use as a direct food additive. Cases of propylene glycol poisoning are related to either inappropriate levels of intravenous or subcutaneous fluid injection use or the accidental consumption of large quantities by children.

What does the FDA say about propylene glycol?

Per the FDA website: http://www.accessdata.fda.gov/scripts/fcn/fcnDetailNavigation.cfm?rpt=scogsListing&id=262
The Select Committee has weighed the available information and concludes that: There is no evidence in the available information on propylene glycol and propylene glycol monostearate that demonstrates, or suggests reason to suspect, a hazard to the public when they are used at levels that are now current or that might reasonably be expected in future.

Who uses propylene glycol outside of electronic cigarettes?
Nearly every consumer product company that produces a skin care product uses propylene glycol in one form or another. Many reputable house hold brand name products contain propylene glycol in their formulations. These companies include but are not limited to: Proctor & Gamble, Unilever, LOreal, Estee Lauder, Colgate Palmolive, RJ Reynolds, Johnson & Johnson, Merck, Pfizer, GlaxoSmithKlein (GSK), Philip Morris to name just a few.

Why/How is propylene glycol used in eCigs?
Electronic cigarettes use propylene glycol as a solution in which to dissolve the nicotine (where legally available). Also, when atomized, propylene glycol creates a mist or vapor which emulates the smoke of a combusting tobacco cigarette. The propylene glycol provides the mouth feel of smoke while circumventing negative combustion effects from traditional tobacco. Unlike tobacco cigarettes, propylene glycol is not burned but rather vaporized to produce a mist. It is this mist that is inhaled and which carries the dissolved nicotine (where legally available) into the lungs. As a result, the mist is at a low temperature, and does not damage the cilia in the lungs, thereby removing the smokers cough that is common with tobacco cigarette smoking.

What is the difference between vapor and smoke?
This is a very important point of differentiation. A vapor is simply an airborne liquid in a diffused state (e.g. a mist or a cloud or fog). You can actually see the small particles of water or fluid in that state moving through the air, taking on the properties of a gas cloud. But in reality, it is simply very small liquid particles. With respect to temperature, a vapor can function at much lower temperatures (e.g fog rolling in at winter time). Another good example of this is a hot shower on a cold day. You can notice the water vapor emerge from the shower and move around the room as if it were smoke because it is being moved around the room by temperature differences and air itself. Remember, a vapor is not a gas, but rather very small particles of the fluid. Clouds in the sky are in fact, simply water vapor. Your warm breath on a cold day is water vapor, not smoke which would be solids suspended in air, not liquids. Condensation of water on window sills or a cold glass of water on a hot day, is the result of water vapor collecting along the surface of glass where the temperature difference induces the water to move from a vapor to a liquid state.

Contrast this with smoke from fires and combustion. Smoke is actually a solid converted to a gaseous state. The molecules within smoke are actually that of a solid material (soot, ash) having been converted to a gaseous state by means of high heat. You will notice that when smoke condenses, it leaves solid material behind in the form of soot and ash. This is the byproduct of the combustion (e.g. cigarette ash, diesel smoke, house fires, volcanoes, etc). Also, another critical point is that the burning or the chemical process by which heat is applied to a solid and is turned into a gas, creates hydrocarbons. It is also important to note here that carbon is an essential building block of human life and plant life on earth (e.g. we are carbon-based life forms). When we apply a high heat in the form of fire to a carbon-based material, there is a carbonization process whereby the non-carbon based material is separated from the carbon atoms in the form of gas, and ash (the left over solid material from the burning process). A common example of a remaining solid is what we all know as charcoal. Charcoal is nothing more than the carbonized form of wood.

Carbon Monoxide
This stuff will kill you.
During the burning process, if there is partial oxidation (or an incomplete burn) there is the creation of
carbon monoxide. Carbon monoxide is also found in car exhaust, which is also a remnant of an incomplete burning of gasoline. Carbon monoxide also happens to be a severe blood toxin in humans, and as it happens also identified as a green house gas. All this said, of these byproducts of carbonization or combustion is not remotely safe for human consumption as they can all serve as carcinogens or mutagens (products that induce cancers and or some mistaken replication of human DNA). When humans inhale tobacco smoke they are, in effect, inhaling a version of the solid material. In fact, the tobacco industry itself refers to the burning portion of any cigarette as the coal. Unlike a vapor, these are solid particles mixed with remnant gases from the combustion process (e.g. carbon monoxide). These particles and gases mix with the natural moisture of the lung and throat at a very high heat no less. These chemical compounds operating at high heat are then absorbed into the human body in a manner that wouldve been impossible prior to the introduction of fire.

Again, it is important to reiterate that unlike a water vapor, smoke is primarily a solid material (e.g. cigarette paper, tobacco leaves, tobacco additives, pesticides, etc). PLUS the added carbon effects from oxidation (aka burning) such as Carbon Monoxide (a blood toxin) being converted into a gaseous state and then ingested into the lungs. It is for this reason that smoking cigarettes in the form of drawing in burning material in the form of smoldering tobacco embers is spectacularly dangerous to human life. Contrast this to inhaling fog on a cold day. There is no comparison as one is safe, the other terribly dangerous. Lastly, it is important to point out that it is not the nicotine (where legally available) found in the tobacco leaf that is at issue in smoking. Rather, it is the delivery mechanism in the form of combustion of tobacco by fire and the inhaling and exhalation of solid particles that is the primary public health issue.

Ive heard that Ethylene glycol and propylene glycol are in Anti-freeze. Whats the difference?

As mentioned before, anti-freeze is simply a solution that is made with a variety of compounds which have much lower freezing points than water. Ethylene glycol and methanol have been used in the past along with other agents that keep metals from oxidizing under high heat. Propylene glycol has been introduced as a non-toxic version of ethylene glycol. Ethylene glycol is, in fact, toxic to humans while propylene glycol is not. It is this reason that propylene glycol was introduced in order to mitigate the risks if animals or children were to ingest the liquid.

It is important to note, however, that propylene glycol is not anti-freeze.
Propylene glycol is simply a suspension fluid that is used because its fluid properties are superior to that of water and that it is safe for human consumption. Comments or references made by industry as to the dangers of electronic cigarettes due to their use of propylene glycol are not only false, but also ironic considering Big Tobacco relies on propylene glycol in much of their processing and manufacturing. Moreover, it is the
FDA itself that has stated that propylene glycol is GRAS or Generally Recognized As Safe for human consumption. But what is even more humorous, is the fact that nearly all the major consumer products companies and pharmaceutical companies rely on propylene glycol for their solutions, mixtures, products, concoctions, potions, medicines, foods and beverages. Arguably, one could ask why we are pouring Duncan Hines cake mix into our cars? Or why we are using Lubriderm, Noxema, and Barbasol in our radiators? The fact remains, that propylene glycol has been highly studied by industry for nearly 40 years and has time and again been shown to be safe. As long as Americans want shampoo, skin creams, make ups, mascara, snow cones, jelly doughnuts, shave cream, soap, eye drops, toothpaste, mouthwash propylene glycol will be a part of their lives.


Is it better to inhale a vaporized propylene glycol + nicotine (where legally available) solution or to continue smoking tobacco cigarettes?
We cannot give medical advice. Nor can we know anything for 100% certainty. However, what we can do is document the risks as the tobacco lobby, the US Congress and medical research has published for us. Moreover, we recommend that you always consult your physician as well as use your personal experience and common sense in assessing the validity of any statement made by anyone, including what you read here in order to make an intelligent, informed decision.

That said, electronic cigarette proponents frame the debate in this way. For those habitual tobacco cigarette smokers who rely on tobacco combustion as their primary nicotine (where legally available) delivery vehicle, electronic cigarettes offer a convenient and useful alternative which lacks the
following chemical compounds commonly found in tobacco cigarettes (among many many others) too long to list here:

Ammonia: Household cleaner
Angelica root extract: Known to cause cancer in animals
Arsenic: Used in rat poisons
Benzene: Used in making dyes, synthetic rubber
Butane: Gas; used in lighter fluid
Carbon monoxide: Poisonous gas
Cadmium: Used in batteries
Cocoa (toxic when burned and inhaled)
Cyanide: Deadly poison
DDT: A banned insecticide
Ethyl Furoate: Causes liver damage in animals
Freon
High Fructose Corn Syrup
Lead: Poisonous in high doses
Formaldehiyde: Used to preserve dead specimens
Methoprene: Insecticide
Megastigmatrienone: Chemical naturally found in grapefruit juice
Maltitol: Sweetener for diabetics
Napthalene: Ingredient in mothballs
Methyl isocyanate: Its accidental release killed 2000 people in Bhopal, India in 1984
Polonium: Cancer-causing radioactive element

Compare this list to Electronic Cigarettes:


Propylene glycol
Nicotine (where legally available)

You are free to decide which you would prefer

Re: Smokers Rights

If smokers are granted the right to choose to smoke tobacco cigarettes, they should also be given the right to know what is in their tobacco in order to make an informed choice. Otherwise, the choice to smoke is essentially a false choice in that smokers are not properly informed as to their alternatives and the relative risk/benefits associated with those choices such that they can make a well-reasoned decision. Up until now, smokers had no choice but to either smoke tobacco cigarettes or quit smoking. Electronic cigarette manufacturers, however, argue that there are reasonable alternatives that smokers should be allowed to consider. Arguably, there is a degree of assumed risk with the consumption of any nicotine (where legally available) delivery device. Modern science has not created a 100% no-risk device. That said, any rational person when presented the option to consume 4,000 additional chemicals or to not consume 4,000 additional and secret chemicals would opt to NOT CONSUME what they cannot identify. The situation is made even worse when combined with alcohol, tobacco additives and contaminants increase the solubility of many of those 4000 chemicals in the blood stream.

Getting a complete listing of all the chemicals used in tobacco cigarettes has been challenging. Lawyers for the Tobacco industry have traditionally refused to give complete lists of their additives under the argument that it would reveal trade secrets. Public health officials, medical professionals as well as the public itself have argued that Trade Secrets are not a strong enough argument to deny smokers their informed consent. Manufacturers of electronic cigarettes present an interesting solution to the Trade Secrets dilemma in that tobacco companies would not be mandated to divulge their trade secrets any longer because consumers will have a choice to purchase only those products that make transparency their hallmark. Therefore, should tobacco companies value their trade secrets more than their consumers right to know, those consumers can choose to take their business elsewhere. Part of that informed consent, then, is allowing smokers to have access to alternative devices in the form of electronic cigarettes.

The Public Health perspective: Harm Reduction or Mitigation
For the most part, the debate around tobacco consumption has been one of smoker versus the tobacco lobby. But recently a new injured party has entered the fray and that is of the general non-smoking public who are exposed to the risk of second hand (direct exposure) and third hand (indirect off gases) smoke. As a group, this plaintiff community dwarfs the smoking community in that it involves everyone who comes in contact with a smoker whether they are smoking in their presence or have done so in the past. In other words, this class of plaintiff is the rest of the world. As a result, recent legislation has banned smoking in public places, government offices, sidewalks, bathrooms, airports, hospitals, etc. Recent research also has shown that places where smokers habituate are also a high risk for non-smokers as the ash and soot and gases are releases into the air and can cause cancer to people when no smoker is actively present. This raises huge concerns for public housing, prisons, state hospitals, universities, military facilities and the like as it might not be possible to truly mitigate the risk of tobacco combustion byproducts for years to come.

How about a game of roulette?
The Harm Mitigation or Harm Reduction approach argues that when weighing the possible solutions to a public health crisis, solutions should be assessed on the greater good notion. In other words, what is the best, reasonable alternative given that there might be negative outcomes no matter what solution you choose? For example, lets stipulate that smoking is bad for ones health. Lets also stipulate that nicotine (where legally available) addiction is a suboptimal state as it drives users to make choices that compromise their health due to their addiction. In other words, the nicotine (where legally available) compulsion supersedes the desire for self-preservation.

What then might be the best approach to the public health challenges that such an addition introduces? If we find that smoking cessation is ineffective and/or too slow to address the pressing needs of the whole human population (smokers and nonsmokers) then a harm reduction approach would argue that we look for those solutions which reduce the overall harm to all parties. In the case of electronic cigarettes, we see immediate possible benefits. First, since there is no combustion, there is no second hand and no third hand smoke concerns at all. And that is an immediate, powerful, long-term success for nonsmokers and smokers alike. Next, electronic cigarettes do not use smoke at all. There is no burning coal or fire element. This means that the fire risk is negated 100%. As an aside, 1,000 people lose their lives each year just in fire related accidents caused by lit cigarettes. Also, because electronic cigarettes are vapor-based, there is no heat from burning smoke that is applied to the lungs. This completely eliminates the singing of throat cilia and the burning of the lining of the lungs. This reduces or eliminates the traditional smokers cough and fluid and mucous build up in smokers lungs due to ineffectual throat and esophageal functioning. Lastly, electronic cigarettes primary delivery solution, propylene glycol, is GRAS (Generally Recognized As Safe) by the FDA and is NOT a known carcinogen.

Moreover, nicotine (where legally available) is not a carcinogen either. Therefore, when taken in total, the opportunities for health benefits to the whole of society outweigh the subtle or potential risks that electronic cigarettes might pose. Again, the argument is not whether electronic cigarettes are as good for you as Vitamin C tablets. But rather, do electronic cigarettes pose a reasonable alternative to the harms currently caused by tobacco combustion? And, when taken in the totality of all smokers AND nonsmokers alike, are the potential harms far outweighed by the immediate benefits described above. And, given the fact that current tobacco cigarette smokers are allowed to continue their habit, should they be allowed the right to know about reasonable alternatives and choose for themselves which risks they wish to assume and why?

It is the electronic cigarette manufacturers position (as well as hundreds of thousands of world-wide customers and family members) that electronic cigarettes (if properly manufactured and used) offer a reasonable alternative to the current dangers of smoking tobacco-based products and should be allowed as a alternative to those who currently smoke tobacco products.

It is NOT the position of these groups that electronic cigarettes are intended for and or marketed to minors with the hopes of capturing increasing market share for the electronic cigarette product due to its higher upfront costs and complexities. In fact, the market opportunity is so large among existing tobacco consumers, that even attempting to pursue a youth-strategy would be a foolish economic mistake. Conversely, tobacco companies require such investment in building youth audiences as smoking tobacco products is something that is hard to convince reasonable adults to do. Therefore, the electronic cigarette manufacturers are neither personally nor economically incented to pursue under age audiences.