What is Propylene Glycol?

February 07, 2019

If you’re familiar with vaping, you’ve probably heard the term ‘PG’ mentioned to describe e-liquid. This abbreviation stands for Propylene Glycol and refers to one of the main substances which forms the base of all e-liquids - the other being Vegetable Glycerin. Both of these liquids are considered extremely safe and non-toxic and by altering the volume of each substance it is possible to achieve different thicknesses, and as such, different vaping experiences.

‘Classic’ e-liquids contain a higher level of PG than VG which helps to create the thin consistency and satisfying ‘throat hit’ often likened to the sensation of smoking. This makes classic liquids the preferred choice for those looking to quit tobacco using a low-wattage Pen-Style Kit.

‘Sub ohm’ liquids, however, have a higher percentage of VG than PG and because VG is a thickening agent, these e-liquids are more suited for high-wattage sub ohm devices which are designed to produce a lot of vapour and very intense flavour.

But what exactly is Propylene Glycol and what are its common uses?

Propylene Glycol is essentially a synthetic liquid additive which is used in food, drink and cosmetic products to provide a number of beneficial effects. PG is odourless and colourless with virtually no distinguishable taste.

PG is able to dissolve certain substances more effectively than water and can retain moisture extremely well. This accounts for the common use of PG in processed food products, as it helps to maintain a stable level of moisture and prevents foods from drying out. Some of the other common uses of PG in consumable and cosmetic products include:

Acting as an anti-caking agent to prevent foods from sticking together.
Extending the shelf life of foods by acting as an antioxidant and protecting against deterioration from oxygen exposure.
Preventing ingredients from separating by acting as an emulsifier.
Prevents food items from drying out by preserving moisture.
Adding texture or thickness to food
Acting as a carrier substance to dissolve other food additives or nutrients to be used in processing, such as colours, flavours and antioxidants.
Enhancing the appearance of certain foods or liquids by making them clearer or more vibrant.

PG is also widely used injectable medications and topical creams and ointments which are applied to the skin, as well as in a variety of personal hygiene and cosmetic products.

Propylene Glycol has an extremely low toxicity rating and after extensive testing it has been found to contain no cancer-causing properties and does not negatively impact genetics or the reproductive system. The same cannot be said for tobacco, of course.

Propylene Glycol and Antifreeze

Unfortunately, the practise of vaping is associated with a number of myths which find their roots in misinformation and scaremongering. Because of this, you may have heard some links being made between PG and antifreeze - a liquid typically added to radiator water to lower its freezing point.

This is because Propylene Glycol is often confused with Ethylene Glycol, a highly toxic substance which is unsafe for human consumption and therefore not used in any consumable or medicinal products.

Although Propylene Glycol and Ethylene Glycol are both used in antifreeze due to their low melting points, they are very different substances, and this should not lead to the safety of PG being questioned.