The Chemical Guide

[*-SARIN-*]

THE CHEMICAL GUIDE
TO THE MOST COMMONLY ENCOUNTERED CHEMICALS AS A VAPER

The Regulars



NICOTINE:



Figure 1 – Nicotine

Description:

Nicotine is chemically classed as an alkaloid, a naturally occurring chemical compound found in plants, specifically the nightshade family. In the body it is a stimulant and a nicotinic acetylcholine receptor (nAChR) agonist (a drug that mimics acetylcholine (ACh)). It is this ability to mimic ACh and bind at the receptor that makes nicotine so addictive!

Dangers:

Nicotine is listed as a poison with a LD50 (Lethal Dose 50 - the amount that it takes to kill 50% of the test subjects) of 0.5-1.0 mg/kg for humans. This figure was disputed in a 2013 report as many people had survived a lot higher doses but it is noted that it has a higher toxicity than other common alkaloids such as caffeine, cocaine, morphine and codeine. Pure nicotine is a dangerous substance and should be used in a fume cupboard with the relevant PPE. The nicotine used in DIY e-liquid production is not generally sold at a level above 100mg/ml (more generally 72 mg/ml for ease of mixing ratios). Even at this strength it is still listed as toxic and should be used in a well-ventilated area with gloves.

Can I overdose on nicotine?

Yes, lots of vapers know the effects of vaping too long or on a higher mg liquid than they would normally use. Symptoms include headache, light-headedness and nausea. Stopping vaping and a little lie down normally cure it within 5 minutes. Drink that bottle of 72mg/ml DIY nicotine and you’ll be having a trip to the hospital.

How do I get hold of DIY nicotine?

Lots of vendors sell it and you normally have a choice of strength (mg/ml) and the base carrier – Propylene Glycol (PG), Vegetable Glycerin (VG) or Aqueous Glycerin (AG). Always buy the highest % nicotine otherwise you are paying for PG, VG, AG unless it suits you to buy a lower strength or the lower strength is significantly cheaper.

Can I get 100% pure nicotine?

Not without a poisons license and not without being flagged as a poison buyer.

Does nicotine go off?

Yes it does is the short answer. This occurs through reaction with oxygen to yield nicotine oxide (amber in colour). Nicotine + Oxygen = nicotine-N’-oxide. It should also be noted that nicotine has high acidity which alters the chemical structure of flavourings in mixed juice and causes the juice to darken over time. The more nicotine % in the juice the quicker and darker the liquid will become.

How do I keep my DIY nicotine in tip-top condition?

What to store it in:

Your DIY nicotine will probably arrive in a plastic bottle but for long term storage I recommend it is stored in amber glass bottles to stop UV degradation and potential chemical leaching caused by the plastic bottle.


How to store it:

If you bought 1 Litre+ then you should decant into smaller quantities so that you aren’t exposing the majority of the nic base to more oxygen every time you want to use it.(Bigger bottle, greater surface area, more oxidation can take place). Ideally when you break the one big bottle down into smaller ones you should leave as little gap as possible between the top of the bottle and the cap, even if this means that some drips down the side when you screw the lid on (use gloves). The issue arises when you dispense some to use, the gap gets bigger unless you do one of two things:

- Top the bottle back up.

- You decant the nic into manageable size bottles in the first place so you can leave it in the fridge for the period that you’ll use it all up

Nic Bases three enemies are heat, UV light (sunlight) and oxygen.


Where in the freezer to store it:

Purely from a safety point of view it’s best to store it at the bottom of the freezer so that if it does leak it doesn’t contaminate everything else in the freezer. I know that some people have a separate freezer for their nic but plenty just stick it in with the meat and veg! Make sure that the bottle is labelled, not just for you but for the other people that fancy a shot of that very chilled “vodka” at the bottom of the freezer. I can confirm that chilled nic base looks very similar to chilled vodka when it is in a glass bottle!


PG, VG or AG as the base carrier:

A personal preference really but with regards to degradation, VG has an extra O-H (alcohol) functional group compared to PG so I suspect degradation takes place quicker if VG is used as the carrier although this is unproven. However, VG has a better shelf life than PG, 2 years compared to 1 generally.


Time Periods:

I would expect to see and experience noticeable degradation after 5 years storage either in taste or colour. Strength drop would need chemical analysis to determine but is expected to be nowhere near half.


What not to do:

Once decanted, leave the bottles alone as the less they are disturbed the better. DO NOT open the bottles if you don’t need to and never shake them as this introduces oxygen to more of the nic base rather than just the surface.


I’ve heard that you can replace nicotine addiction with caffeine?

You can’t directly replace nicotine with caffeine; they are two different types of chemical that work on two different receptors in the body. Caffeine is a CNS stimulant that blocks adenosine attachment to G-protein coupled receptors (responsible for drowsiness) whereas nicotine is a nicotinic acetylcholine receptor (nAChR) agonist as mentioned above. It would be a bit like trying to replace a crack addiction by swapping to heroin – you would develop two addictions rather than one. It should also be noted that vaping juice with caffeine in it does nothing because the volumes are so small.


Propylene Glycol:



Figure 2 – Propylene Glycol

Description:

Propylene Glycol (PG) also known as propane-1,2-diol is a colourless liquid that has a faint sweet taste. It’s a hygroscopic liquid meaning that it attracts and holds water molecules, ie. It dehydrates you.

Dangers:

PG is safe to handle but a very small minority have allergic reactions. Symptoms include; inflamed dry skin in the facial area, small red spots on the body, contact dermatitis.

What is it used for?

Vapers will encounter PG as either a base carrier in DIY nicotine or as an additive in making e-liquid. In e-liquid manufacture it is used as a flavour carrier and produces the “throat hit” feeling. The downside is that it produces less vapour than other carriers.

What other uses does it have?

PG is added to many food stuffs including; ice cream, liquid sweeteners. It is also used as a carrier to administer drugs either intravenously, orally or topically. With a freezing point of -59º C it is often used as an environmentally friendly anti-freeze.

NOT TO BE CONFUSED WITH:

Ethylene Glycol that is the active ingredient in anti-freeze and is toxic to humans.

Does it go off?

Yes, PG has a shelf life of around 1-2 years from the date of manufacture under normal storage conditions.



Vegetable Glycerin / Glycerol / Glycol:



Figure 3 – Vegetable Glycerol

Description:

Vegetable Glycerol (VG) is a viscous, colourless and odourless liquid with a sweet taste. Just like PG it is a hygroscopic chemical.

I see it called Vegetable Glycerin, Glycerol and Glycol, what’s the difference?

To the common person Vegetable Glycerin / Glycerol /Glycol are essentially the same thing but to an organic chemist they are different albeit on a slight technicality. Glycerol’s proper chemical name is propan-1,2,3-triol and is classed as an alcohol in organic chemistry (the “ol” in triol gives this away, the “tri” means that there are 3 alcohol groups (-OH).

Glycerin is a commercial term used when there is more than 95% glycerol in the substance. It may also be called Glycerine, Propantriol or 1,2,3-trihydroxypropane depending on the nomenclature naming convention used.

Dangers:

None. Classed as non-toxic.

What is it used for? 

Vapers use VG in a very similar way to PG, ie. It is used either as an additive in making e-liquid or as a base carrier in DIY nicotine. Unlike PG, VG is mainly used to produce vapour in e-liquid manufacture and does not give the “throat hit” that PG does.

What other uses does it have?

It is used extensively in the food industry either as a sweetener or to keep food moist. It is also added to toothpaste, skin, hair and soap products. Too much taken orally will produce a laxative effect.

Does it go off?

Yes. It has a shelf life or around 2 years under normal storage conditions.

What is Aqueous Glycerine (AG)?

AG is VG that has been made less viscous by the addition of water. 5-10% water by volume is the recommended amount to add. AG is often used by people with a PG allergy that want a Glycerol heavy liquid that is not super viscous



Flavourings:


Description:


High intensity liquids that contain a flavour, sometimes a sweetener and a carrier, normally PG

You will come across flavourings if you mix your own e-liquid as well as pre-made liquid. The flavourings used are the same as those used in the food industry. A little goes a long way with flavourings with very few recipes asking for more than 20% of the total liquid volume to be flavourings.


Are there any flavourings that I shouldn’t use?

Yes, any that are oil based because vaping oil is not good for your lungs. A simple test to tell if the flavouring has oil in it is to put a drop into a glass of water. If it floats on the top then you should assume that it has oil in it and not use. Once added to your other e-liquid ingredients it will also separate, indicating that something isn’t right.


Can I make my own flavourings?

Yes but there are some items that you cannot use;

Citrus fruits are generally high in oil (the peel) and it is this that attracts / defends against insects. Oranges, lemons and limes are all high in oil and these types of flavourings tend to be synthetically made rather than naturally for this reason. The same can be said for a lot of the spices and mints.

Lots of vegetables contain added “ingredients” during the growing process, the classic example being neonicotinoids, although rarer these days. These are the compounds that are affecting bees and have been given a 2 year ban by the EU but they are still in the soils and distribute to every part of the plant / vegetable during growth. Other insecticides could contain potentially harmful compounds that require specialist chemical removal.

Coffee needs to be used with caution as the bean contains oil and requires advanced chemical knowledge of solvents to rid any resulting extract of the oil.


***See the Nasties section for further information on other problematic substances that you might be tempted to use***


What can I use to extract my desired flavour?

PG and VG can be used for this process although there is some indication that Ethyl Acetate could be used in the extraction of fruit flavour as it is of low toxicity and is found naturally in the chemical makeup of fruit aromas and wine

Lots of DIY flavour makers use 100% proof vodka as the solvent to extract flavours but 100% proof is not the same thing as 100% alcohol. Alcohol proof is twice the alcohol content by volume so your vodka is only 50% alcohol, the remaining 50% will be water and ? The volume of unknown substance is being added to your extraction! Read that line again!


Steeping:

In the sense of the word, steeping is the process of the infusion of flavours into a liquid so this applies to making your own flavourings as described above. However the vaping community has adopted steeping as meaning that a liquid has “mellowed” and ready to vape. You cannot speed up the process of making a liquid “steeped”, this requires patience and time for the chemicals to break down. No amount of shaking, heating or using ultrasonic can do this. All it will do is make sure that the ingredients of the liquid are sufficiently mixed.


Why do certain flavours damage tanks?

Certain flavours contain citric acid or sharpening agents that will crack tanks and strip paint either by exploiting naturally occurring weaknesses in the tank materials or by slowly breaking down the paint over time.


Other e-liquid additives:

Menthol crystals – added to give a mentholated feeling. Menthol crystals are available at Boots or online and are generally safe to handle (don’t rub them in your eyes though, that hurts). To make menthol flavouring you just add the crystals to the carrier (PG / VG or AG) and then either heat the liquid gently in warm water or in your pocket. It should be noted that if the liquid gets cold the crystals may re-appear, just re-warn to dissolve them again. It doesn’t take a lot of crystals to make a super strength menthol additive, use sparingly.


***Gentle reminder***

The majority of pre-extracted flavourings used in e-liquids are only tested for consumption, not inhalation, and a lot of research is still on going into the effects of these products after heating and inhalation. If you are not familiar with basic chemistry and handling chemicals it best to stick to using pre-extracted flavours. There’s so many pitfalls using chemicals it’s unreal, one missed step or miscalculation and things can go very wrong very quickly with very serious consequences. Saying that, noting new was discovered by playing safe. Just ask the niggling question before ploughing headlong into the unknown, no one will laugh. Better to be safe than sorry, or waste a load of chemicals!




THE NASTIES



ALDEHYDES:





Figure 4 – An Aldehyde

Description:

Aldehydes are organic compounds that contain a formyl functional group (R-CHO), with formaldehyde (methanol), being the most basic aldehyde.

Dangers:

Aldehydes are very reactive due to their formyl group and occur naturally in essential oils, vanillin, cinnamon and coriander (remember why you shouldn’t make DIY flavours from herbs and spices, this is another reason!) The fact that none of the body’s natural building blocks (amino acids, lipids or nucleic acids) contain aldehydes should also red flag them as potential problematic items.

Formaldehyde:




Figure 5 – Formaldehyde

Formaldehyde is a colourless gas and is listed as carcinogenic, toxic and harmful. Due to its high reactivity it is commonly used as a precursor to other chemical compounds, specifically and mainly industrial resins. As its boiling point is -19º C it will nearly always be found as a gas.

Vanillin:




Figure 6 - Vanillin

This phenolic aldehyde (one of my favourite sniffy liquids in a lab, the other being amyl acetate – pear drops) is the primary component of the vanilla bean. The majority of flavourings that DIY mixers of e-liquid use is synthetic vanillin as it’s less expensive but has exactly the same chemical structure.

Cinnamaldehyde:


Figure 7 - Cinnamaldehyde

Cinnamaldehyde is a pale yellow thick liquid and the primary component of cinnamon bark that gives the unique flavour and odour. Cinnammon essential oil is roughly 98% cinnamaldehyde. It is of low toxicity but a known skin irritant.

Acrolein:


Figure 8 – Acrolein

Also known as propenal, acrolein is a colourless liquid with a particularly nasty acrid smell; in fact it is one of my least favourite chemicals for its nasal offending abilities. Think burning fat! Acrolein is again highly reactive and hence highly toxic, there’s a bit of a theme here eh? Its ability to be a strong irritant of the nasal passage, eyes and skin should be no surprise to non-smokers as it is one of the major non-carcinogenic components of tobacco smoke (40%). Acrolein is listed as highly poisonous, highly irritant and extremely flammable both as a liquid and gas.

Can aldehydes be produced by exposing Propylene Glycol (PG) to far higher temperatures in my tank than vapers will ever normally vape at?

Not really, at least not in any great quantities and not by just heating PG more than you normally would. Aldehydes and specifically formaldehyde is produced from burning.

Can aldehydes be produced from dry hits?

The hard and fast answer is yes! There have been numerous junk studies where the researchers have discovered aldehydes in the test results. In all of these studies the atomiser coil was heated to a lot higher temperature and for a longer period of time than would normally happen. If you’ve ever had a dry hit you will know that it’s unpleasant and stop fairly quickly.

Are there more aldehydes in tobacco smoke than e-liquid?

Yes, considerably more. As mentioned above, aldehydes are normally produced as a product of burning.

DIKETONES:

Description:

Diketones are organic molecules containing two ketone functional groups. The simplest diketone is diacetyl - ut oh!

Diacetyl:


Figure 9 – Diacetyl

Diacetyl also called butanedione or butane-2,3,-dione depending on the naming convention is a yellow / green liquid with an intense butter flavour that occurs naturally in alcoholic drinks as a by-product of fermentation. Common uses include being used in foodstuffs to give them a buttery taste. Diacetyl is known to cause Bronchiolitis obliterans, more commonly known as “popcorn lung” after several microwave popcorn factory workers in the US developed it after inhaling heated diacetyl over a long period of time. It is listed as harmful and flammable. The majority of e-liquids these days are diacetyl free.

Acetylpropinoyl:


Figure 10 - Acetylpropinoyl

Also known as 2,3-pentanedione it’s a diketone with an aroma that is described as one of the following; nutty, fruity, cheesy, buttery or caramel. Acetylpropinoyl is known to cause respiratory tract damage and fibrosis to the lungs. Just like diacetyl, this compound is being found less frequently in e-liquids as manufacturers respond to the concerns of the public and studies by Farsalinos et al who stated that the addition of diacetyl and acetylpropinoyl to e-liquid posed an unnecessary risk to vapers

Acetoin:


Figure 11 – Acetoin

Acetoin, also known as 3-hydroxybutanone or acetyl methyl carbinol and although not a diketone, is the intermediate to diacetyl. It should come as no surprise that the molecules look similar and it shares the same characteristics; a yellow / green liquid with a buttery flavour. It is used by the food industry in exactly the same way.

ALCOHOLS:

Ethanol – or more commonly vodka is used to give the throat hit feeling if PG isn’t present in the e-liquid. Generally added at less than 5% by volume.

Isopropyl Alcohol (propan-2-ol)


Figure 12 – Isopropyl Alcohol

More commonly known as rubbing alcohol is used by vapers to clean drippers, tanks and the sticky residue left after removing labels. It is a colourless liquid that is extremely flammable, has a strong odour and known to be a skin irritant (it can be absorbed through the skin, use gloves). *** DO NOT DRINK IT, NOT EVEN A LITTLE BIT! ***



So there we are, at the end. Some of you with a snifter of interest may notice that a lot of the chemicals mentioned have similar molecular structures or contain the same elements. It is no coincidence that where you find diacetyl you will probably find acetylpropinoyl or acetoin, or the fact that PG and VG look almost identical.



Final Note:

This is by no means a comprehensive list of all the chemicals that you might come across as a vaper but it goes someway to listing the most common ones. Any chemical that is not handled or used safely can cause you serious damage. If you are unsure please seek advice.