E-liquid, or e-juice, is the name for the solution that’s heated up and converted to an aerosol, which e-cigarette users inhale.
So what does E-liquid contain?
Flavours and nicotine are dissolved in hygroscopic (absorbs water from the air) components, which turn the water in the solution into vapour when heated. Commonly used hygroscopic components include propylene glycol, vegetable glycerine, and polyethylene glycol 400, often sold under the abbreviations PG, VG, and PEG 400, respectively.
Safety of liquid base
All three liquid bases are common food additives used in common pharmaceutical formulations. The current dominating liquid base is Propylene glycol and has been utilised in asthma inhalers and nebulizers since the 1950s. Because of its water-retaining properties, is the compound of choice for delivering atomized medication. It meets the requirements of acceptable compounds within Title 21 ofthe Code of Federal Regulations.
The main prominent base fluid of e-liquid tends to be Propylene Glycol (PG) or it can also be Vegetable Glycerine (VG). Contents of the e-liquid solutions vary, but their common aspects include water and flavourings in a propylene glycol or glycerine base. Nicotine is also included in solutions intended to fulfil a nicotine replacement role. PG or VG liquid is used as the carrier to provide the nicotine to the user; however users also can use electronic cigarettes with zero nicotine content e-liquid. The base fluids produce the smoke simulations visible when used with an appropriate electronic cigarette device.
Hundreds of different flavour varieties are available, such as regular tobacco and menthol. A wide variety of food flavours are also sold, from sweet or traditional flavours like (vanilla, coffee) to the most exotic (strawberry, watermelon, mango).
All flavours are subjective, and each person will have a subjective experience of the taste.
Liquid solutions containing nicotine are available in differing nicotine concentrations to suit user preference. Dosing nomenclatures are not standardised and vary by manufacturer, but tend towards the following rough figures
Liquids said to contain ‘low’ doses of nicotine tend to correspond to a nicotine concentration of 6–8 mg/ml (milligrams of nicotine per millilitre of liquid).
‘Midrange’ doses tend to correspond to a nicotine concentration of 10–14 mg/ml.
‘High’ doses tend to correspond to a nicotine concentration of 16–18 mg/ml.
‘Super-high’ doses tend to correspond to a nicotine concentration of 24–36 mg/ml.
Actual numerical nicotine concentration ratings are usually printed on liquid containers or cartridge packaging.
In general, the higher the nicotine content, the stronger the throat hit, which is the sensation the user experiences at the back of the throat upon inhalation from the electronic cigarette device.