The safety of propylene glycol has been evaluated and confirmed by international and national authorities. Both the Organisation for Economic Cooperation and Development (OECD), and the Canadian Centre for Occupational Health and Safety, have published risk assessments that conclude propylene glycol has very low toxicity.
In Europe propylene glycol used in pharmaceuticals applications must follow strict specifications for quality as laid out in the European Pharmacopoeia. The 8th edition of this official document of the European Directorate for the Quality of Medicines (EDQM) was published in 2013 and is used in more than 37 countries in Europe.
In the US, propylene glycol is regulated by the US Food & Drug Administration (FDA) and must meet the specifications for pharmaceutical grade material laid out in the United Stated Pharmacopeia. US Pharmaceopeia/National Formulary (USP/NF) chapter <467> imposes certain limits on Residual Solvents present as impurities in drug substances, excipient and products.
The European authorities responsible for consumer health have approved the use of propylene glycol with food:
The United States FDA has affirmed propylene glycol as Generally Recognized as Safe (GRAS) when used:
Propylene glycol used in food applications must meet the specifications of the US Food Chemicals Codex. The caloric content of propylene glycol is 4 cal/g according to the definition of a carbohydrate as defined by the FDA in 21 CFR § 101.9(c)(1)(i)(B).
As of October 2010 propylene glycol is an approved animal feed material according to Regulation (EC) No 767/2009. It is listed in the Catalogue of Approved Feed Materials (Regulation(EU) 68/2013) and in the EU Register of Feed Materials.
The US FDA affirms propylene glycol is GRAS (except in cat food) as a general animal feed additive in 21 CFR § 582.1666 or as an emulsifying agent in 21 CFR § 582.4666 when used in accordance with good manufacturing or feeding practice. The FDA has determined that propylene glycol is not safe for use in or on cat food, and such use causes the feed to be adulterated and therefore in violation of the Federal Food, Drug and Cosmetic Act (21 CFR § 589.1001).
In 1994, the Cosmetics Industry Safety Panel (of CTFA, Cosmetic, Toiletry and Fragrance Association, known today as “The Personal Care Products Council”) confirmed propylene glycol to be safe for use in cosmetic articles, and at higher concentrations than those actually used in consumer products.
In Europe Regulation (EC) No 1223/2009 on Cosmetic Products works on the principle of a “negative” list which defines substances that are prohibited or restricted for use in cosmetics. Propylene Glycol is not on this list.
The Regulation (EC) No 1907/2006 concerning Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) requires producers and importers of chemical substances in quantities of above 1 ton per year to register with the European Chemicals Agency (ECHA). The registration dossier contains detailed information on the substance's intrinsic properties and hazards, a detailed use mapping, and, for hazardous substances, an exposure and risk assessment. As propylene glycol is not classified as hazardous, exposure scenarios and risk assessments are not required.
The Propylene Glycol Producers in the EU have worked together in a Consortium to jointly address the registration requirements of propylene glycol. For further details on this please visit the dedicated Propylene Oxide-Propylene Glycols REACH webpage managed by REACHCENTRUM.
Please be aware that the registration is valid for the molecule propylene glycol (CAS No 57-55-6) with a defined substance identification agreed in the Consortium, which is different from the quality specifications necessary for industrial vs. pharmaceutical applications.
Most countries have adopted the UN Globally Harmonised System (GHS) for Classification and Labelling. In Europe GHS is implemented under Regulation (EC) No 1272/2008, also known as the CLP Regulation. In the United States GHS is implemented under the OSHA Hazard Communication Standard (HCS). Propylene Glycol is not classified as hazardous under GHS.