Vapor Transmission: The Ongoing E-Cigarette Thing

Background: A few months ago a friend of mine sold his e-cigarette kit to me for $10. He was trying to quit smoking and it didn't work for him very well. The first time I tried his I was still smoking menthols, and the particular type of fluid he was using made me cough -- pretty much like non-menthol cigarettes used to. I didn't think about trying an e-cigarette then, mostly because of that first experience and because they were supposedly cost-prohibitive. I later tried a fluid called "Nu-Port (the name varies sometimes)," and found it was a decent substitute for light menthol cigarettes. I cut down on those and then eventually was able to quit completely and exclusively use the e-cigarette, and I still use it now.

Information: There's an ongoing exchange going on between the FDA and e-cigarette makers and importers now, because e-cigarettes aren't regulated yet. They supposedly originated in China, our great partner for cheap and somewhat shitty products. I usually wouldn't risk using a product unless it was approved by the Food and Drug Administration, but I did some limited research into the supposed composition of nicotine fluid beforehand, and found that the risk was worth the chance to let my lungs heal after 12 years of smoking half a pack or more a day.

If you don't know, an e-cigarette is basically a tiny vaporizer inside a tube, which connects to a power source, such as a battery, on one end and a mouthpiece on the other. Some batteries are manual, with a button which engages the vaporizer, while other batteries are "automatic" and work by sensing suction. I use the former. The usual mouthpiece found on most e-cigarettes is normally called a "cartridge" containing a cotton-type fiber filler which holds the fluid containing nicotine. The soaked fiber comes in contact with the vaporizer, allowing the fluid to be inhaled. Many companies (often advertising late at night in cheap infomerical-style ads) market their e-cigarettes with the option to buy only new pre-filled cartridges, while other businesses sell separate parts and bottles of the fluid. The vaporizer is often called an "atomizer," even though I seriously doubt it breaks compounds into their respective atoms.

Diagram I made for my girfriend's mom

Personal Experience: I started using an e-cigarette with the above-mentioned setup: battery, vaporizer, and plastic cartridges containing the cotton-type filler. While this worked somewhat well, I started to notice several drawbacks of this method:

1. Short Range: with the amount of vapor I was inhaling, I used a lot of battery power, charging and changing batteries frequently; if I was in public, I'd often run out of power fairly quickly
2. More Repetition: Not only was I changing batteries lot, but I was also constantly removing the cartridge to add more fluid; the buildup of dried unused material from the fluid would accumulate in the filler, making it less able to hold new fluid, which led to everything being
3. Messy: Constantly refilling the cartridges leads to overflow; the fluid would often end up on the outside of the e-cigarette and get on my hands a lot, which is kind of gross
4. More Chores: Due to the filler material accumulating buildup, I would often soak the filler in water, dry it, and place it back in the cartridges, of which I probably had around six

Eventually one of my two batteries died. I was going through probably three to five charges a day. Luckily I was able to find a website which sells different parts for very cheap, and ordered a new battery, vaporizer, and a "pass-through," which is a modified battery which plugs into a USB port. This seriously alleviated any problems relating to power, but I haven't been able to use it in my car for some reason with an adapter that came with my smartphone.

Another option I had heard of was the "drip tip," but I wasn't sure how it worked exactly. After receiving my new parts in the mail, I found the drip tip to be a mouthpiece (metal or plastic) which does not include any filler, doesn't hold nicotine fluid, and allows the user to apply fluid and inhale vapor directly from the vaporizer itself. It's basically a solid tube which works very well with the small nicotine fluid bottles I normally use.

Nickel-Plated Drip Tip (left) and USB Pass-Through (vaporgalaxy.com)

There are only two drawbacks I've found so far pertaining to the drip tip:

1. Potential Crackpipe Lips: the vaporizer generates a lot of heat when used for long periods at a time, which transfers through the drip tip and to the lips; I'm not sure if a plastic tip would be any better though as it might eventually melt
2. Potential Burny-Dry Throat: Inhaling directly from the vaporizer can sometimes be a little more harsh; the vapor burns the throat a little more, but this can be remedied by adding more fluid to the vaporizer; while you might find you produce much more vapor using the drip tip, it often will taste slightly burnt once the vaporizer gets dry, so if you don't like the burnt taste you'll most likely be adding more fluid and keeping the vapor less burny all-around

These two drawbacks are easily remedied, and overall using the pass-through/drip tip combination is much better than using a cartridge, and much more convenient than using batteries only. The metal drip tip makes the weight of the e-cigarette as a whole more even when using the heavy batteries, and is much cleaner than using cartridges.

Ongoing Regulatory Situation: This week the FDA stated it plans to regulate e-cigarettes as tobacco products, and has done some analysis of some e-cigarette cartridges offered by retailers in the U.S. This means importers and producers of fluid will most likely be prohibited from selling (or making) flavored fluids other than menthol in accordance with the new Family Smoking Prevention and Tobacco Control Act of 2009, which prevents flavored cigarettes from being sold in the U.S.

I'm personally a supporter of regulation, as long as it isn't (in this case) influenced by tobacco industry lobbying (to prevent more of their customers from moving to e-cigarettes), is based on otherwise unbiased scientific research, and isn't influenced by uninformed public opinion. This may seem like a given, but regulation in it's smartest and most effective form prevents us from using products which can harm us to varying degrees. Since the FDA obviously allows tobacco products to still be sold to and used by Americans, it stands to reason they would allow e-cigarettes and nicotine fluid to be sold as well if the level of harm is can cause to people is equal to or less than tobacco products. Also, it's important to note the FDA also allows prescription drugs with harmful and fatal side effects to be sold in the U.S. and advertised on television ad nauseum, so if any kind of intelligence is applied to the research into harmful effects of e-cigarettes and they are harshly regulated or banned, such action would be justified, and I would assume multiple users would have come forward in the last year or so with health problems and complaints.

Furthermore, regulation will allow the government to tax e-cigarette-related products and hold producers to some standard as to the chemical composition of fluids available. As long as e-cigarettes and materials are available as a cost-effective alternative to now expensive cigarettes, regulation will be positive.

Substances Used In E-Cigarettes: Supporters and users of e-cigarettes have so far been knowledgeable regarding the composition of nicotine fluids they use and/or sell, and provide information on some ingredients used to produce it, but no one is required to provide information on what e-cigarette fluids actually contain. Despite the lack of regulation so far, fluid can normally be identified as "PG-based" (propylene glycol-based), or "VG-based" (vegetable glycerine-based). 

From what I can tell, α-propylene glycol-based fluids seem to be more popular and sold more often. Wikipedia describes propylene glycol as: 

"a colorless, nearly odorless, clear, viscous liquid with a faintly sweet taste, hygroscopic and miscible with water, acetone, and chloroform. The acute oral toxicity of propylene glycol is very low, and large quantities are required to cause perceptible health damage in humans; propylene glycol is metabolized in the human body into pyruvic acid (a normal part of the glucose-metabolism process, readily converted to energy), acetic acid(handled by ethanol-metabolism), lactic acid (a normal acid generally abundant during digestion),^[9] and propionaldehyde.^[10][11] Serious toxicity generally occurs only at plasma concentrations over 1 g/L, which requires extremely high intake over a relatively short period of time.^[12] It would be nearly impossible to reach toxic levels by consuming foods or supplements, which contain at most 1 g/kg of PG. Cases of propylene glycol poisoning are usually related to either inappropriate intravenous administration or accidental ingestion of large quantities by children.^[13] The potential for long-term oral toxicity is also low. In one study, rats were provided with feed containing as much as 5% PG in feed over a period of 104 weeks and they showed no apparent ill effects.^[14] Because of its low chronic oral toxicity, propylene glycol was classified by the U. S. Food and Drug Administrationas "generally recognized as safe" (GRAS) for use as a direct food additive. Prolonged contact with propylene glycol is essentially non-irritating to the skin. Undiluted propylene glycol is minimally irritating to the eye, and can produce slight transient conjunctivitis (the eye recovers after the exposure is removed). Exposure to mists may cause eye irritation, as well as upper respiratory tract irritation. Inhalation of the propylene glycol vapors appears to present no significant hazard in ordinary applications. However, limited human experience indicates that inhalation of propylene glycol mists could be irritating to some individuals. Therefore inhalation exposure to mists of these materials should be avoided. Some research has suggested that propylene glycol not be used in applications where inhalation exposure or human eye contact with the spray mists of these materials is likely, such as fogs for theatrical productions or antifreeze solutions for emergency eye wash stations.^[15] Propylene glycol does not cause sensitization and it shows no evidence of being a carcinogen or of being genotoxic.^[16][17] Adverse responses to intravenous administration of drugs which use PG as an excipient have been seen in a number of people, particularly with large dosages thereof. Responses may include "hypotension[,] bradycardia... QRS and T abnormalities on the ECG[,] arrhythmia[,] cardiac arrest[,] serum hyperosmolality[,] lactic acidosis[,] and haemolysis".^[18] A high percentage (12% to 42%) of directly-injected propylene glycol is eliminated/secreted in urine unaltered depending on dosage, with the remainder appearing in its glucuronide-form. The speed of renal filtration decreases as dosage increases,^[19] which may be due to propylene glycol's mild anesthetic / CNS-depressant -properties as an alcohol.^[20] In one case, administration via IV of PG-suspended nitroglycerin to an elderly man may have induced coma and acidosis.^[21] According to a 2010 study by Karlstad University, the concentrations of PGEs, propylene glycol and glycol ethers in indoor air, particularly bedroom air, has been linked to increased risk of developing numerous respiratory and immune disorders in children, including asthma, hay fever, eczema, and allergies, with increased risk ranging from 50% to 180%. This concentration has been linked to use of water-based paints and water-based cleansers.^[22][23][24]

and is used in the following capacities:

• As a solvent in many pharmaceuticals, including oral, injectable and topical formulations. Notably, diazepam, which is insoluble in water, uses propylene glycol as its solvent in its clinical, injectable form.^[5]
• As a humectant food additive, labeled as E number E1520
• As an emulsification agent in Angostura and orange bitters
• As a moisturizer in medicines, cosmetics, food, toothpaste, shampoo, mouth wash, hair care and tobacco products
• As a carrier in fragrance oils
• As an ingredient in massage oils
• In hand sanitizers, antibacterial lotions, and saline solutions
• In smoke machines to make artificial smoke for use in firefighters' training and theatrical productions
• In electronic cigarettes, as a vaporizable base for diluting the nicotine liquid
• As a solvent for food colors and flavorings
• As an ingredient, along with wax and gelatin, in the production of paintballs
• As a moisture stabilizer (humectant) for snus (Swedish style snuff).
• As a cooling agent for beer and wine glycol jacketed fermentation tanks
• As a non-toxic antifreeze for winterizing drinking water systems, and in applications where the used antifreeze eventually will be drained into the soil, water, or a septic system.^[6]
• As a less-toxic antifreeze in solar water heating systems
• As a solvent used in mixing photographic chemicals, such as film developers
• In cryonics
• As a working fluid in hydraulic presses
• As a coolant in liquid cooling systems
• To regulate humidity in a cigar humidor
• As the killing and preserving agent in pitfall traps, usually used to capture ground beetles
• As an additive to pipe tobacco to prevent dehydration.
• To treat livestock ketosis
• As the main ingredient in deodorant sticks.
• To de-ice aircraft.^[7]
• As an ingredient in UV or blacklight tattoo ink
• As a lubricant in air conditioning compressors.
• As a wetting agent, used to determine drying time in paints and coatings

The FDA stated several of the products they tested didn't hold true to the information sellers have provided about them, with some products labeled "nicotine-free" actually containing nicotine. In May 2009, the FDA issued a report on their analysis, which stated certain cartridges (fluids) contain small amounts of carcinogenic substances (tobacco-specific nitrosamines) such as cotinine, nicotine-N-oxide, nornicotine, anatabine, anabasine, pseudooxynicotine, myosmine,  β-nicotyrine, and also stated "Nicotine-N-oxide, nornicotine, anatabine, pseudooxynicotine and MNP were not observed in any of the samples." Diethylene Glycol, a poisonous organic compound, was detected in one of the samples.

I believe it's safe to formulate possibilities based on the available information as to how harmful e-cigarette vapor consumption is to humans relative to consumption of other potentially harmful products contained in readily available items purchased in the U.S.:

1. Cigarettes and other tobacco products
2. Ingredients in food such as High Fructose Corn Syrup and transfats
3. Charred meat, hot dogs
4. Common ingredients such as sugar, salt, etc.

Until everyone is purchasing products held to certain standards and specifications and those products are thoroughly tested, no one can say for sure how harmful e-cigarettes are, and further testing will benefit everyone. However, the facts so far are these: e-cigarettes don't produce chemicals in the form of smoke, and may in fact be less harmful in that respect than smoking marijuana. They don't leave a sometimes offensive and lingering odor, don't cause wildfires or litter, and most likely do not contain the same additives found in cigarettes, which are engineered as a nicotine delivery device by tobacco companies to optimize nicotine consumption.