You read labels.

You flip the bottle.

You squint at the ingredient list and try to decode what in the goddess-given universe “PEG-200 Hydrogenated Glyceryl Palmate” actually means.

And you still might not know what’s in your cleanser.

That’s not a failure of your intelligence. That’s the beauty industry working exactly as designed.

Let’s talk about PEGs in skincare — polyethylene glycol compounds — what they are, how they’re made, what they do inside your skin, and why some of the most trusted brands in the game are absolutely loaded with them.

What Are PEGs in Skincare and Why Are They Everywhere?

Polyethylene glycols, or PEGs, are a family of synthetic compounds used across the cosmetics industry as emulsifiers, surfactants, cleansing agents, and — here’s the part they don’t put in the marketing copy — penetration enhancers.

They’re in cleansers. They’re in moisturizers. They’re in body lotions, shampoos, conditioners, and baby products. According to independent testing by the Environmental Working Group, 1,4-dioxane — a byproduct that can result from PEG manufacturing — has been detected in roughly 22 percent of products in their cosmetics database. More on that in a moment.

PEGs are cheap to produce. They play well with other ingredients. They make formulas feel smooth and luxurious. They help actives absorb more efficiently. From a formulation standpoint, they’re incredibly useful — which is exactly why they’re everywhere.

But useful for the formula and safe for your body are two very different conversations. And the beauty industry has been hoping you wouldn’t ask to have both.

The Manufacturing Process Nobody Talks About

Here’s where it gets real.

PEG compounds are made through a process called ethoxylation — a chemical reaction that involves adding ethylene oxide to other ingredients to make them milder and more water-soluble.

Ethylene oxide is a known human carcinogen. The International Agency for Research on Cancer (IARC) classifies it as Group 2B — meaning there is sufficient evidence of its carcinogenicity in experimental animals (showing increased liver cancer and nasal tumors in rodents) but inadequate evidence in humans. It’s the same chemical used to sterilize medical equipment.

Now, the argument you’ll hear from the industry is that the ethylene oxide is consumed in the reaction — it gets used up in the process of making the PEG compound. And that’s largely true. But ethoxylation is not a perfect process. And when it’s imperfect, it can leave behind a contaminant.

That contaminant is called 1,4-dioxane.

1,4-Dioxane: The Carcinogen That Doesn’t Have to Be on the Label

The EPA classifies 1,4-dioxane as “likely to be carcinogenic to humans” based on sufficient evidence from animal studies. The National Toxicology Program has echoed that classification.

To its credit, the FDA does require cosmetic manufacturers to follow Good Manufacturing Practices — and minimizing contamination like 1,4-dioxane is part of that framework. So the FDA is aware this is a concern, and responsible manufacturers take steps to reduce it.

But here’s where the framework falls short: there is no requirement to test finished products for 1,4-dioxane. No requirement to disclose results if testing is done. And because it’s not technically an “ingredient” — it’s a manufacturing byproduct, something that can appear as a result of how other ingredients were made — it does not have to appear on the label under current law.

The Environmental Working Group, which does conduct independent product testing, has detected 1,4-dioxane in roughly 22% of cosmetic products in their database — including 97% of hair relaxers and 57% of baby soaps tested. That’s third-party testing. It’s not required, not standardized, and not something consumers can access at the point of sale.

You can read every single word on that label, do everything right, and still have no way of knowing whether that product was manufactured with the care to minimize contamination — because the regulatory framework decided that “unintentional” means “unlisted,” and that “following best practices” doesn’t need to be verified or disclosed.

That’s not transparency. That’s a technicality being used as a shield.

The Penetration Enhancer Problem

Beyond the manufacturing contamination issue, there’s a second concern that deserves its own spotlight: PEGs are penetration enhancers.

Your skin has a barrier — the stratum corneum — whose entire job is to keep the outside world out. It determines what absorbs, what bounces off, and what never makes contact with deeper layers of tissue. It is one of your body’s most sophisticated defensive systems.

PEG compounds interfere with that barrier. They temporarily disrupt the tight junctions in the stratum corneum, allowing ingredients to absorb more deeply than they otherwise would.

For an active ingredient you actually want delivered — a vitamin C complex, a targeted therapeutic — that might sound like a feature. But in a multi-ingredient formula, penetration enhancement is indiscriminate. It doesn’t just carry the good stuff deeper. It carries everything deeper. Every preservative, every fragrance compound, every synthetic stabilizer in that same bottle gets a more direct route past your skin’s defenses.

When you read “PEG” on a label, you’re not just reading about one ingredient. You’re reading about a delivery mechanism for everything else in that formula.

One of the most trusted drugstore skincare brands on the market. Affordable, widely recommended, and picked up by millions of people who are genuinely trying to do right by their skin. A brand owned by one of the largest beauty corporations in the world, with some of the most sophisticated cosmetic chemists on their payroll.

Their most popular cleansing oil contains the following PEG compounds:

• PEG-200 Hydrogenated Glyceryl Palmate
• PEG-120 Methyl Glucose Dioleate
• PEG-7 Glyceryl Cocoate
• PEG-150 Pentaerythrityl Tetrastearate
• PEG-6 Caprylic/Capric Glycerides

That’s five. In a single cleanser. Along with Polysorbate 20 and PPG-5-Ceteth-20 — additional ethoxylated compounds that raise the same concerns.

This is not a formulation accident. This is a deliberate choice by a company with the resources, the scientists, and the regulatory knowledge to formulate without these compounds if they wanted to.

They don’t want to. PEGs are cheap, effective, and legal. And the regulatory environment has made it very easy to not disclose the full picture.

“Dermatologist recommended” is a marketing designation. It is not a safety certification. It is not a toxicological review. It is not a promise that every ingredient in that formula has been evaluated for long-term human health outcomes.

It means some dermatologists recommended it. That’s it.

Research ⁷ has shown:

• Rich in antioxidants that fight environmental toxins, boost collagen, resulting in firmer skin and fewer wrinkles.
• Reduces inflammation, redness, and swelling, which again is helpful for conditions like psoriasis, eczema, and sunburnt skin.
• Promotes skin cell growth and regeneration, supports wound healing, and can improve the appearance of scars.
•  Enhances skin’s moisture levels, strengthens the skin barrier, and improves texture and softness.
• Shows effectiveness against some bacteria, fungi, and infections, helping with blemishes

This isn’t a call to throw everything in your cabinet in the trash. It’s a call to stop letting “I trust this brand” do the work that “I read the actual label” needs to do.

When you see PEGs in skincare, ethylene glycol, polysorbate, or any ingredient ending in “-eth-” — that’s an ethoxylated compound. That’s the flag. That’s the moment to ask what else is in the formula, and whether you want a penetration enhancer escorting it past your skin barrier.

You are not a “unit of consumption.” You are not someone to be marketed at and sent on your way. You are a person with the right to make fully informed decisions about what you put on your body — and that requires more information than the current label system provides.

The fog of the uninformed is not your fault. But once the information is in front of you, clarity is a choice.

Choose it.

This is for educational purposes only. The information provided is based on available regulatory data and industry research at the time of publication. Cosmetic regulations and ingredient safety assessments may evolve, and readers should verify current information with the FDA and other regulatory authorities.

While we strive for accuracy, some industry statistics and historical references may not reflect the most current regulatory landscape. Always consult product labels and contact manufacturers directly for the most up-to-date ingredient information.

This document is not intended as medical advice. Individual reactions to cosmetic ingredients may vary. When in doubt, consult a dermatologist or healthcare professional.

Sources:

Cancer-Causing Chemical 1,4-Dioxane Contaminates Americans’ Drinking Water: https://www.ewg.org/news-insights/news/cancer-causing-chemical-14-dioxane-contaminates-americans-drinking-water

1,4-Dioxane (1,4-Diethyleneoxide) https://www.epa.gov/sites/default/files/2016-09/documents/1-4-dioxane.pdf

1,4-Dioxane in Cosmetics: A Manufacturing Byproduct : https://www.fda.gov/cosmetics/potential-contaminants-cosmetics/14-dioxane-cosmetics-manufacturing-byproduct

IARC Carcinogen Update : https://pmc.ncbi.nlm.nih.gov/articles/PMC1280416/