What is Propylene Glycol (PG)?

Propylene Glycol

PG is a clear liquid and is odorless, colorless and tasteless. It is derived out of petrochemical sources. PG, one of the most versatile substances that has ever been produced, is extensively used in the food, cosmetic, chemical and pharmaceutical industries. PG has been the main ingredient in e-liquids since the introduction of electronic cigarettes.Propylene Glycol molecular structure

It is because of its emulsifying properties that PG is made use of as the base for e-liquids. PG helps to keep the other ingredients (which would not mix together) added to it in suspension. Additionally, it enables the process of atomization at temperatures that are lower compared to the temperature at which tobacco in traditional cigarettes burns as well as carries nicotine to the user’s lungs.

People start talking about so many things if you mention the word PG or propylene glycol. Some people will scare you, saying that you are inhaling car antifreeze compound. Some others will tell you that it is poisonous material. They are not totally wrong because PG is at times included as an ingredient in antifreeze agents in order to replace the hazardous ethylene glycol which can cause harm to animals that lap up leaking antifreeze. However, the difference is that PG used in antifreeze compounds is of industrial grade. On the other hand, PG used in e-liquids is of food-grade quality that is approved by Health Canada to be used in many consumable products. Food-grade PG is a commonly used additive in pharmaceutical inhalers and food products. 

Research studies related to the consumption of PG have been carried out since the 1940s and it has been inhaled by human beings from the 1950s onwards when it was used for sanitizing the air within environments such as eateries, hospitals, commercial establishments, institutions, houses, bathrooms, etc. No serious health issues have been reported till date.

All said and done, PG may not be a totally harmless substance. Cases of allergic reaction being experienced by vapers due to the use of e-liquids have been reported but is very rare. PG is also known to be an irritant as well as humectant (helps tissues to absorb moisture better). Therefore, PG is not entirely harmless taken in extreme high quantities or used by sensitive individuals but it is not known to be carcinogenic. However keep in mind it is certainly not as hazardous as tobacco smoke.