Is propylene glycol safe? How it differs from antifreeze, where it's allowed, and what it's in
Where propylene glycol is allowed
United States
PermittedThe FDA affirms propylene glycol as generally recognized as safe (GRAS) in food under 21 CFR 184.1666, at levels not exceeding current good manufacturing practice; the regulation lists category levels of 2.0% for all other food categories, 5% in alcoholic beverages, 2.5% in frozen dairy products, 24% in confections and frostings and 97% in seasonings and flavourings. For cosmetics, the CIR expert panel (set up and funded by the cosmetics industry's trade association, which says the panel works independently; it is not a regulator) concluded propylene glycol is safe as used when formulated to be non-irritating. [1, 2, 8, 10]
Canada
Permitted with conditionsHealth Canada's lists of permitted food additives allow propylene glycol for defined uses, including as a carrier solvent in flavour and food-additive preparations and as an anticaking agent in salt (up to 350 ppm). In cosmetics, it does not appear on Health Canada's Cosmetic Ingredient Hotlist of prohibited or restricted ingredients (page updated August 2025). [4, 5, 6]
European Union
RestrictedAccording to EFSA's 2018 re-evaluation, propylene glycol (E 1520) is not authorised to be added directly to food in the EU, and the consolidated Regulation (EC) No 1333/2008 (version of 18 August 2026) lists it in Annex III only as a carrier: in colours, emulsifiers and antioxidants (1,000 mg/kg in the final food, as carry-over), and in food enzymes, flavourings and nutrients. From all sources, the total in food is capped at 3,000 mg/kg, or 1,000 mg/L in beverages other than cream liqueurs. EFSA found no reason to change its acceptable daily intake (ADI) of 25 mg per kg of body weight per day. [7, 11]
What is propylene glycol?
Propylene glycol is a clear, colourless, slightly syrupy liquid that is practically odourless and tasteless, according to ATSDR (the US Agency for Toxic Substances and Disease Registry). ATSDR says it is used to absorb extra water and hold moisture in some foods, cosmetics and medicines, and as a solvent for food colours and flavours.
The antifreeze confusion comes from the name. Ethylene glycol and propylene glycol have structures that differ by only one methyl group, yet ATSDR says they behave very differently: it describes ethylene glycol as a potent cause of acute toxicity in humans, while propylene glycol is a 'generally recognized as safe' additive for foods and medications. ATSDR also says propylene glycol does not form harmful crystals when it breaks down in the body. Propylene glycol is used to make some antifreeze and de-icing products, which adds to the mix-up.
Why it's used, and where you'll find it
In food, propylene glycol is a solvent and vehicle that carries flavours and colours, a humectant that holds in moisture and an anticaking agent, among other roles listed in the FDA regulation. In cosmetics, the Cosmetic Ingredient Review (CIR) expert panel says it acts as a skin-conditioning agent, viscosity-decreasing agent, solvent and fragrance ingredient, and that it can act as a penetration enhancer for some chemicals under some conditions, helping other ingredients move into skin.
What the research and regulators say
Why it is not the same as ethylene glycol
ATSDR describes ethylene glycol as a potent cause of acute toxicity in humans, and says propylene glycol does not form harmful crystals when it breaks down. EFSA reports that propylene glycol is readily absorbed and that the major route of metabolism is oxidation to lactic acid and pyruvic acid. ATSDR's clinical guidance says no adverse health effects are likely from normal use of propylene glycol products; serious effects have been described mainly after large doses given over a short period in medical settings (such as intravenous medicines that use it as a solvent) and after prolonged, extensive application to compromised skin such as burns. Both ATSDR and EFSA note that infants clear it more slowly than adults. [2, 3, 7]
What EFSA found for the food additive
EFSA's 2018 re-evaluation found no treatment-related effects in subchronic studies at 1,000 mg per kg of body weight per day, no genotoxicity concern, and no adverse effects, including tumours, in a two-year rat study at up to 2,500 mg per kg per day. It concluded there was no reason to revise the ADI of 25 mg per kg, which the EU's Scientific Committee on Food set in 1996 (JECFA allocated the same figure in 1973). In its refined, brand-loyal exposure scenario, estimated exposure from the reported uses did not exceed the ADI in any population group (the highest 95th-percentile estimate was 23.3 mg per kg per day, in children), though EFSA thought exposure was probably overestimated. It recommended lowering the lead limit in the EU specifications and adding limits for propylene oxide, mono- and di-ethylene glycol and propylene carbonate. [7]
On the skin, irritation is the main question
The CIR panel's published 2012 assessment says propylene glycol is generally non-toxic and non-carcinogenic, and that clinical studies showed no skin sensitization (an allergy-type reaction) at use concentrations, although concerns about irritation remained. According to the June 2010 draft of that amended report, which we could open in full, reactions appeared in some people at concentrations as low as 10% in predictive tests and 2% in provocative tests, and 6.0% of patients in one pooled patch-test analysis reacted to a 30% water solution. The panel's original 1994 conclusion capped use at 50%; after reviewing use studies of deodorants with 35% to 73% propylene glycol and a sensitization test of an antiperspirant with 86%, it amended the conclusion to 'safe as used when formulated to be non-irritating'. ATSDR likewise says frequent skin contact can sometimes irritate the skin. [2, 8, 9]
Who might choose to avoid it
People who have had a skin reaction to propylene glycol in a moisturiser, deodorant or similar product may want to check ingredient lists, since the CIR review found irritation in some people. None of the sources reviewed here tells the general population to avoid it in food.
How to spot it on a label
In food, look for 'propylene glycol' or 'E 1520' (the EU wording is 'propane-1,2-diol'); in cosmetics the ingredient-list name is 'propylene glycol'. Propylene glycol alginate (E 405) and propylene glycol esters of fatty acids (E 477) are different additives, though EFSA notes propylene glycol can be formed when the body metabolises them, and none of these is ethylene glycol.
Check what's in your own productsScan a barcode or a label photo and Label X-Ray flags propylene glycol and everything else in plain English, with your allergies checked automatically.
Frequently asked questions
Is propylene glycol antifreeze?
Propylene glycol is used to make some antifreeze and de-icing products, according to ATSDR, but it is a different substance from ethylene glycol, which ATSDR describes as a potent cause of acute toxicity in humans. The two differ by one methyl group, and the FDA treats propylene glycol as generally recognized as safe in food.
Is propylene glycol banned in Europe?
No. According to EFSA, E 1520 is not authorised as an ingredient added directly to food, but it is permitted as a carrier for food additives, enzymes, flavourings and nutrients, within limits.
Is propylene glycol banned in Canada?
No. Health Canada's lists permit it for defined uses, including as a carrier solvent and as an anticaking agent in salt at up to 350 ppm. It is not on the Cosmetic Ingredient Hotlist.
Is propylene glycol safe for skin?
The CIR panel concluded it is safe as used in cosmetics when formulated to be non-irritating. Some people do react with irritation, though clinical studies showed no skin sensitization at use concentrations.
Related ingredients
Sources
- eCFR (U.S. Government) — 21 CFR 184.1666 - Propylene glycol (accessed 2026-09-19)
- ATSDR (CDC) — Propylene Glycol | ToxFAQs (accessed 2026-09-19)
- ATSDR (CDC) — Ethylene Glycol and Propylene Glycol Toxicity: What is Propylene Glycol? (accessed 2026-09-19)
- Health Canada — 15. List of Permitted Solvents (Lists of Permitted Food Additives) (accessed 2026-09-19)
- Health Canada — 1. List of Permitted Anticaking Agents (Lists of Permitted Food Additives) (accessed 2026-09-19)
- Health Canada — Cosmetic Ingredient Hotlist (accessed 2026-09-19)
- EFSA Journal (via PubMed Central) — Re-evaluation of propane-1,2-diol (E 1520) as a food additive (accessed 2026-09-19)
- PubMed (U.S. National Library of Medicine), CIR Expert Panel report — Safety assessment of propylene glycol, tripropylene glycol, and PPGs as used in cosmetics (Fiume et al., Int J Toxicol 2012;31(5 Suppl):245S-260S; PMID 23064775) (accessed 2026-09-19)
- Cosmetic Ingredient Review (CIR) — Propylene Glycol, PPGs, and Tripropylene Glycol: draft final amended report, CIR Expert Panel meeting book, June 28-29, 2010 (accessed 2026-09-19)
- Cosmetic Ingredient Review (CIR) — About the Cosmetic Ingredient Review (accessed 2026-09-19)
- EUR-Lex (European Union) — Consolidated text: Regulation (EC) No 1333/2008 of the European Parliament and of the Council on food additives (version of 18 August 2026), Annex III (accessed 2026-09-19)
This page summarizes what regulators and published research say, as of the review date above. Rules and evidence change; check the linked sources for the latest. It is general information, not medical advice — talk to a doctor or pharmacist about your own health.