Learn More About Propylene Glycol
E-Liquid is the fluid used with electronic cigarettes that is heated with an atomizer in order to produce flavours (and optionally nicotine) which can then be inhaled in the form of a vapour. Propylene Glycol (PG) is a common component of E-Liquid. Propylene Glycol, also called propane-1, 2-diol, is an organic compound. It’s a viscous colourless, liquid that’s nearly odourless and used on a large scale in food processing.
An E-Liquid will typically contain either Vegetable Glycerin (VG), Propylene Glycol (PG) or both - and these are the ingredients in E-Liquids that give off the smoke-like vapour. PG based E-Liquids tend to have a thinner consistency than VG based E-Liquids, which can mean tha PG E-Liquids produce a stronger throat hit; more similar to that of tobacco cigarettes. This is one reason why some vapers prefer PG E-Liquids. Some vapers find the flavour of PG E-Liquid is less sweet than VG and therefore it’s easier to taste the other flavourings added to E-Liquids.
PG based E-Liquid tends to be a popular choice for vapers, due to it’s ability to product a strong throat hit. However, some E-Cigarette users find that Propylene Glycol causes an allergic reaction. This can manifest as an excessively dry mouth/throat, or as an irritation in the respiratory tract.
Research suggests that consumers who cannot tolerate PG probably experience a form of irritation, but that it is rare to develop allergic contact dermatitis. Other investigators believe that the incidence of allergic contact dermatitis to propylene glycol may be greater than 2% in patients with eczema.
PG in Food
Propylene Glycol is used as a humectant (E1520), solvent, and as a food additive and preservative. PG is also used in various foods such as coffee, ice cream, whipped dairy products and fizzy drinks. Medical vapourizers used for pharmaceuticals can often include propylene glycol among the ingredients with which they are filled.Propylene Glycol is used as a solvent in many oral, injectable and topical pharmaceuticals, such as for diazepam and lorazepam.
The acute oral toxicity of propylene glycol is very low, and large quantities are required to cause perceptible health damage in humans.
Chemically it’s classed as a diol and is miscible with a broad range of solvents, including water, acetone, and chloroform.