What Products and Foods Contain Polyethylene Glycol?

Polyethylene glycol, usually called PEG, turns up in a remarkably wide range of everyday products, from the tablet coating on your daily vitamin to the moisturizer on your bathroom shelf. It is used in pharmaceuticals, cosmetics, food supplements, industrial applications, and even agricultural chemicals. The compound goes by several names on ingredient labels, which makes it easy to encounter without realizing it. Understanding where PEG actually appears, and how much you’re likely to come into contact with, helps put common safety concerns in perspective.

What PEG Actually Is and Why It Shows Up Everywhere

PEG is a synthetic, water-soluble polymer made by linking together repeating units of ethylene oxide. It comes in a range of molecular weights, from liquid forms like PEG 200 and PEG 400 to waxy solids like PEG 4000 and above. The number after “PEG” on a label tells you roughly how heavy the molecule is, and that weight determines what the compound does in a given product. Low-molecular-weight PEGs act as solvents and help dissolve other ingredients. Higher-molecular-weight versions form films, thicken formulas, or add a slippery, moisturizing feel.

What makes PEG so versatile is that it dissolves easily in water, is chemically stable, and interacts gently with biological tissues. It is also commercially available under numerous synonyms, including macrogol, oxyethylene polymer, and laureth-9, among others.¹ That naming jumble is one reason people often don’t realize they’re using PEG-containing products. On a shampoo bottle, you might see “PEG-40 hydrogenated castor oil.” On a laxative box, the label might say “polyethylene glycol 3350” or just “macrogol.” In European food regulations, it appears as E 1521.

Pharmaceuticals and Medical Products

The pharmaceutical industry is probably the single largest user of PEG. It is widely used to improve the stability, solubility, and circulation time of drugs in the body, whether those drugs are traditional pills, injectable biologics, or advanced nanoparticle therapies.² In tablet and capsule manufacturing, PEG serves as a binder, a filler, and a plasticizer in film coatings. That glossy, smooth shell on many pills and supplements is often a PEG-containing coating that controls how quickly the drug dissolves in your stomach.

Beyond coatings, PEG is an active ingredient in some medications. Polyethylene glycol 3350 is the main component in many over-the-counter osmotic laxatives, where it draws water into the intestine to soften stool. It is also the base for bowel-prep solutions used before colonoscopies. In injectable medicines, a process called PEGylation attaches PEG chains to proteins or small molecules to slow their breakdown in the bloodstream, meaning patients need fewer doses. Several widely prescribed biologic drugs rely on PEGylation.

PEG-lipids have also become essential in lipid nanoparticle formulations, the delivery system used in mRNA vaccines. In that role, PEG-lipids provide structural stability, help control particle size, and influence how the nanoparticles distribute through the body.³ PEG can also be found in cough syrups, ointment bases, eye drops, ear drops, and topical wound gels. In short, if you take any kind of medication on a regular basis, chances are good that at least one of them contains PEG in some form.

Food and Dietary Supplements

PEG’s role in food is narrower than many people assume. It is not widely added to grocery-store items the way emulsifiers like lecithin or thickeners like xanthan gum are. In the European Union, PEG is authorized as a food additive (E 1521) primarily for one specific purpose: as a plasticizer in the film-coating formulations applied to food supplement tablets and capsules.⁴ When you swallow a multivitamin or fish oil capsule with a smooth, shiny outer layer, PEG may be part of that coating.

The European Food Safety Authority assessed exposure from this use and estimated that people who regularly take food supplements consume up to about 3.5 mg per kilogram of body weight per day on average, and up to about 6.1 mg/kg per day at the high end.⁵ Those figures fall within the range of acceptable daily intakes set by both European and international food safety bodies. PEG also shows up as an indirect food additive in processing and packaging, which is a separate category discussed below.

In the United States, the FDA classifies certain PEG compounds as “generally recognized as safe” (GRAS) for specific uses, including as a solvent or coating agent. You won’t typically see PEG listed on a bag of chips or a loaf of bread, but it can appear in processed foods as a carrier for flavors or colors. PEG’s presence in food is, for most people, limited to supplements and incidental contact from packaging rather than deliberate addition to the food itself.

Cosmetics and Personal Care Products

Walk through the personal-care aisle and PEG is hard to avoid. PEGs and their derivatives are broadly used in cosmetics as surfactants, emulsifiers, cleansing agents, humectants, and skin conditioners.⁶ The specific products include:

Shampoos and body washes: PEG-based surfactants help create lather and remove oil from skin and hair.
Moisturizers and lotions: PEG acts as a humectant, pulling moisture into the skin, and as an emulsifier that keeps oil and water phases from separating.
Toothpaste: PEG helps bind and stabilize the paste, giving it a smooth texture.
Deodorants and antiperspirants: PEG can serve as a solvent for fragrance ingredients or as a base for stick formulations.
Makeup: Foundations, primers, and lipsticks frequently contain PEG derivatives that improve spreadability and wear.

The number following PEG in a cosmetic ingredient list indicates its molecular weight, which in turn tells you its function. Low-numbered PEGs (like PEG-6 or PEG-8) are thin liquids often used as solvents. Mid-range PEGs (PEG-20 through PEG-100) commonly appear as emulsifiers. High-numbered PEGs (PEG-150 and above) tend to be thickeners. You’ll also see PEG attached to other compound names, like PEG-40 stearate or PEG-7 glyceryl cocoate, which are PEG-modified versions of fatty acids tailored for specific cosmetic tasks.

Food Packaging

An area that doesn’t get much public attention is PEG’s use in the materials that touch your food rather than the food itself. Researchers have investigated PEG as a plasticizer in biodegradable food packaging films made from plant-based starches. In one study, sago starch films blended with PEG showed improved water vapor and oil barrier properties, with PEG 1000 offering the best moisture resistance.⁷ PEG is also used as a plasticizer in polylactic acid (PLA) films, a common bioplastic. Adding PEG to PLA dramatically increases the film’s flexibility, but the PEG can migrate out of the material and into the food it contacts. Advanced processing techniques like reactive extrusion have been shown to reduce that migration substantially, lowering it from roughly 140 mg per kilogram in standard PLA-PEG films to about 41 mg per kilogram in reactively processed versions.⁸

This is worth knowing because food packaging is a less obvious source of PEG exposure. Even if the food inside the wrapper contains no PEG at all, trace amounts from the packaging material can transfer to the food. The amounts involved are small, but for people who are particularly sensitive to PEG, packaging is a potential contact route that rarely comes up in conversation.

Household and Industrial Products

Outside the medicine cabinet and kitchen, PEG appears in a surprising variety of industrial and household settings. It is used in wood preservation, for instance. Waterlogged archaeological wood, the kind recovered from shipwrecks and ancient sites, cracks and warps badly when it dries. Treating it with PEG replaces the water in the wood cells and prevents that damage.⁹ The famous Vasa warship in Stockholm, salvaged from the harbor floor in the 1960s, was famously treated with PEG over many years to preserve its timbers.

PEG is also found in ink formulations for printers, in industrial lubricants and metalworking fluids, in textile finishing agents that soften fabric, and in certain household cleaning products. In agricultural chemistry, PEG is sometimes used as a dispersant to help spread active ingredients in pesticide formulations. Research has shown that when PEG is used to disperse insecticides, it can increase the cellular uptake of certain chemicals in mammalian cells compared to water-based dispersions, though the effect varies greatly depending on the specific insecticide involved.¹⁰

How Your Body Handles PEG

One reason PEG is considered safe for so many applications is that the body doesn’t do much with it. When you swallow PEG, most of it passes through the gastrointestinal tract without being absorbed. In healthy people, only a small fraction of orally ingested PEG crosses the intestinal lining. One study measuring urinary recovery of orally administered PEG (in the molecular weight range of 414 to 1206) found that healthy volunteers excreted an average of about 6.5% of what they’d swallowed, with considerable variation between individuals.¹¹ Whatever PEG does get absorbed is excreted largely unchanged by the kidneys.

Skin absorption is similarly limited. PEGs are minimally absorbed through intact skin, and higher-molecular-weight versions (roughly 4000 and above) show essentially no penetration at all. Lower-molecular-weight PEGs, below about 3350, can penetrate to some extent and may even enhance the absorption of other chemicals applied alongside them.¹² Damaged skin changes the picture, as injury increases PEG penetration regardless of molecular weight.

When Absorption Increases

The “most people absorb very little” story has some important caveats. People with inflammatory bowel conditions absorb significantly more PEG through the gut lining than healthy individuals do. In a study that deposited PEG 600 directly into the colon, patients with active ulcerative colitis absorbed several times more PEG than patients in remission or healthy controls. The active-colitis group excreted roughly 3 to 4% of the instilled PEG in urine within six hours, compared to less than 1% in the other groups.¹³

A parallel situation exists for skin. In people with atopic dermatitis (eczema), PEG penetrates uninvolved skin, that is, skin that looks normal and unaffected, at roughly twice the rate seen in people without the condition.¹⁴ The barrier dysfunction underlying eczema apparently extends beyond the visible rash. For someone with eczema who uses multiple PEG-containing skincare products daily, cumulative exposure could be meaningfully higher than estimates based on healthy-skin models would suggest.

PEG Allergies and Hypersensitivity

True allergic reactions to PEG are uncommon but real, and they have received more attention since the rollout of mRNA vaccines, which contain PEG-lipids. PEG can trigger reactions ranging from mild contact dermatitis to anaphylaxis. Part of the challenge is that PEG is present in so many unrelated products that a person with a PEG allergy may have repeated exposures before the trigger is identified. PEG can appear as an active ingredient in a laxative, an excipient in an antibiotic, and a base ingredient in a moisturizer, and different formulations or dosages of the same drug may or may not contain it.¹⁰

Making matters worse, the inconsistent naming described earlier means that a person told to avoid PEG might not recognize “macrogol” or “polysorbate 80” (a PEG derivative) on a label. Clinical allergists have argued that standardized labeling of PEG and its derivatives across drugs, cosmetics, and food products would help patients avoid accidental exposure.¹ If you’ve had an unexplained allergic reaction to a product and the cause was unclear, PEG is worth discussing with an allergist, especially if the reaction happened after taking a medication or using a cosmetic product.

Spotting PEG on Labels

The trickiest part of managing PEG exposure is recognizing it across different types of products, because the naming conventions vary by industry. Here are the common names and label conventions to watch for:

PEG followed by a number: PEG 400, PEG 3350, PEG 8000. The number is the approximate molecular weight.
Macrogol: The international nonproprietary name used in pharmacy, especially in Europe. Macrogol 4000 is the same thing as PEG 4000.
E 1521: The European food additive code for polyethylene glycol.
PEG-compound combinations: PEG-40 stearate, PEG-100 distearate, PEG-7 glyceryl cocoate. These are PEG-modified fatty acids common in cosmetics.
Polysorbates: Polysorbate 20, polysorbate 60, polysorbate 80. These are PEG derivatives of sorbitan esters, widely used in food, drugs, and cosmetics.
Laureth, ceteth, steareth: Followed by a number (e.g., laureth-9). These are ethoxylated fatty alcohols, essentially PEG chains attached to different fatty molecules.

Reading ingredient lists with these names in mind gives you a much clearer picture of your actual PEG exposure than simply scanning for the letters “PEG.” For anyone with a confirmed PEG sensitivity, printing and carrying a list of these synonyms can be genuinely useful when shopping.

Regulatory Standards and Acceptable Intake

Multiple regulatory bodies have evaluated PEG’s safety. The European Food Safety Authority’s assessment found that the highest estimated exposure from its use as a food additive falls within the acceptable daily intake range previously set by both the EU’s Scientific Committee on Food (up to 5 mg/kg body weight per day for PEG 300–4000) and the international Joint FAO/WHO Expert Committee on Food Additives (up to 10 mg/kg body weight per day for PEG 200–10000).⁵ In 2006, the EFSA Panel specifically concluded that PEG consumption from its use as a plasticizer in film coatings for food supplement tablets is not a safety concern at intended use levels.⁴

For cosmetics, the Cosmetic Ingredient Review panel in the United States and its European counterparts have repeatedly assessed PEG compounds and found them safe for use at concentrations typical in consumer products. The key caveat is that PEG should not be applied to damaged or broken skin, because absorption increases sharply and could carry along other ingredients that wouldn’t normally penetrate intact skin.

What Happens to PEG in the Environment

Given how widely PEG is used, it inevitably ends up in wastewater. PEG is not acutely toxic to aquatic organisms at typical environmental concentrations, but its persistence and mobility in water systems are a legitimate concern. Wastewater treatment plants break down some of it, though the efficiency depends heavily on temperature and the type of treatment. Data from a full-scale wastewater treatment facility found that during warmer months, roughly half of the incoming PEG was biodegraded, while in cooler months, that figure dropped to under half, with a larger share passing through into the effluent.¹⁵

Researchers are actively exploring biological approaches to cleaning up PEG-contaminated water. Certain bacteria, including species of Pseudomonas, can use PEG as their sole carbon and energy source, breaking the polymer’s chemical backbone apart. Laboratory studies have confirmed that Pseudomonas stutzeri can degrade PEG 400, rupturing its ether bonds and producing new chemical groups in the process.¹⁶ The work is still at the lab bench rather than deployed at scale, but it points toward potential bioremediation strategies for industrial discharge containing PEG. Whether PEG presents a real ecological threat at current environmental concentrations remains a more open question than its well-studied human safety profile.

1
PubMed Central. Immediate hypersensitivity to polyethylene glycols in unrelated products: when standardization in the nomenclature of the components of drugs, cosmetics, and food becomes necessary
2
PubMed. Anti-PEG antibodies in nanomedicine: Mechanisms, risks, and opportunities
3
PubMed Central. Beyond PEG: Emerging Polymer Lipid Alternatives for Lipid Nanoparticle (LNP) Formulations
4
EFSA Journal. Refined exposure assessment of polyethylene glycol (E 1521) from its use as a food additive
5
PubMed Central. Refined exposure assessment of polyethylene glycol (E 1521) from its use as a food additive – Section: Abstract
6
PubMed Central. Safety Evaluation of Polyethylene Glycol (PEG) Compounds for Cosmetic Use – Section: Abstract
7
Journal of Physics: Conference Series. Properties investigation of sago starch plasticized with Polyethylene Glycol (PEG) and glycerol as food packaging material – Section: Abstract
8
PubMed Central. Enhancing Polylactic Acid Films With Polyethylene Glycol-Based Plasticizers: A Reactive Extrusion Approach
9
PubMed. Preservation of Old, Waterlogged Wood by Treatment with Polyethylene Glycol
10
PubMed Central. Hypersensitivity to polyethylene glycol in adults and children: An emerging challenge
11
PubMed. Gastrointestinal permeability to polyethylene glycol: an evaluation of urinary recovery of an oral load of polyethylene glycol as a parameter of intestinal permeability in man
12
PubMed Central. Role of Polyethylene Glycol in Dermatology – Section: Pharmacokinetics
13
PubMed Central. Increased absorption of polyethylene glycol 600 deposited in the colon in active ulcerative colitis
14
Journal of Investigative Dermatology. Altered Penetration of Polyethylene Glycols into Uninvolved Skin of Atopic Dermatitis Patients – Section: Results
15
Applied Water Science. Enhanced reduction of polyethylene glycol concentrations in the effluent of a full-scale MBBR processes – Section: Abstract
16
PubMed Central. Microbial transformation of PEG 400 by Pseudomonas stutzeri: implications for environmental remediation – Section: Abstract