Today, we invite you to shed light on a component present in your e-liquids that is often debated: Propylene Glycol or PG. The propylene glycol is a chemical made by the reaction of propylene oxide with water. For decades propylene glycol has had an unsurpassed reputation for safe use in a wide range of consumer products, including food products, animal feed, cosmetics and pharmaceuticals, as well as industrial applications.
NO MORE CONFUSION WITH ETHYLENE GLYCOL
The first thing that is too often a source of controversy is that propylene glycol is not used as a component of antifreeze! It should therefore not be confused with ethylene glycol which is harmful to it.
With the unique combination of properties propylene glycol fulfills various roles in different environments.
- It can be used as a solvent
- binds and stabilizes insoluble fluids (the emulsifier)
- aids in binding and transporting other substances (excipient)
- captures and dissolves active substances also in a medium
- attracts water / moisture (hygroscopic)
- lowers the freezing point
- increases the boiling point
- outstanding stability with high flash and boiling points
The molecule propylene glycol is chemically neutral, and usually does not react with other substances. This is a particularly useful property when seeking to combine contrasting chemical elements, for example in a perfume, to create a simple and homogeneous fluid. By emulsifying the active substances, which otherwise would not mix, propylene glycol creates a stable homogeneous fluid that will allow the finished products, whether it is a face cream or a shampoo, to do its job.
SIMPLE PROCESS
In the traditional manufacturing process the propylene glycol is made from propylene oxide reacted with water. The resulting mixture of mono, Di and tri-glycols is distilled to purify the different categories before being stored and distributed to customers. The production of propylene glycol is monitored throughout the manufacturing process up to the point of delivery. A high level of product quality, and compliance with strict hygiene conditions, qualifies the propylene glycol USP / EP (pharmaceutical grade) for use in healthcare applications.
WHERE DO YOU FIND IT?
Le propylene glycol is found in a multitude of applications and consumer products:
In food and beverage, food, cosmetics and pharmaceutical applications, Propylene Glycol USP / EP (Pharmaceutical Grade) is used, for example, to dissolve seasoning in beverages, to preserve animal feed , to homogeneously emulsify oily and aqueous elements, or as a solvent (excipient) for active substances in medicines.
In industrial applications propylene glycol is used as an intermediate to make other chemicals, such as unsaturated polyester resins which are used in baths and kitchenware. It is also used to make plastics, resins, paints and coatings, and plays an important role as an ingredient in formulations for heat transfer fluids, liquid detergents or de-icers.
Le propylene glycol USP / EP (pharmaceutical grade) has been approved for use as an additive under the E-number E 1520. In direct contact with food it is mainly used as a flavor or color carrier in food and beverage manufacturing processes, to make beverages, cookies, cakes, sweets thickener, purifier and stabilizer in food and beverage such as beer, salad dressings or baking mixes In indirect contact with food, ie. during food processing of industrial food products or in food packaging, the propylene glycol USP / EP (pharmaceutical grade) serves as a heat transfer fluid in cooling and freezing applications, and as a solvent for food packaging printing.
Le propylene glycol USP / EP (pharmaceutical grade) is used as an inactive agent (excipient) and is found in body lotions, deodorant sticks, lipsticks and many other cosmetic items, it also acts as a carrier of the active substances in vaccines , cough relief syrups or gel capsules to help deliver these substances into the body for the treatment and prevention of disease.
SAFE USE
For over 50 years The effects of using propylene glycol are fully known and well controlled. It has been used safely for over 50 years, including adoption in health-sensitive applications such as 
food, cosmetics and pharmaceuticals, where the molecule primarily serves as an ingredient or inactive carrier of other substances. Studies have shown that propylene glycol has an extremely low degree of toxicity.
For the environment, studies have shown that propylene glycol is not persistent (it is readily biodegradable). Accordingly, there is no hazard classification of propylene glycol.
The authorities confirm the safety of propylene glycol. Several international authorities have studied the safety of propylene glycol. The Organization for Economic Co-operation and Development (OECD), and the Canadian Center for Occupational Health and Safety, have published risk assessments which indicate the very low toxicity of propylene glycol. If propylene glycol is used in pharmaceutical applications, strict quality specifications as set out in the European Pharmacopoeia, must be followed. The European authorities responsible for consumer health have approved the use of propylene glycol with food: in direct contact with food (Directive 95/2 / EC and amendments) as an additive E1520; in indirect contact with food (Directive 2002/72 / EC and amendments) relating to plastics and articles intended to come into contact.
PROPYLENE GLYCOL AND THE HUMAN BODY
In the human body, propylene glycol is rapidly metabolized and excreted. Its metabolic pathway is comparable to that of sugar: propylene glycol is quickly converted into lactic acid, in a similar way to what occurs with sugar (energy) in muscles during sport, propylene glycol is, therefore, naturally present in our body. It is excreted through the urine.
In the environment, tests have shown that propylene glycol is readily biodegradable. Studies prove that propylene glycol has a very low degree of toxicity. From a toxicological point of view, alcohol is more toxic than the same amount of propylene glycol.
IN CONCLUSION
The controversy around propylene glycol is irrelevant, it is a well-mastered product, known and used for decades. Propylene glycol has been recognized as non-toxic for the human body and biodegradable for the environment. As a result, e-cigarette users will be able to continue to use propylene glycol-based filters with confidence.
