How to Read a Skincare Ingredient Label for Microplastics
Share
Every cosmetic sold in the US must list its ingredients by INCI (International Nomenclature of Cosmetic Ingredients) name, in descending order by concentration. Microplastics are no exception; brands that use them are required to list them. The gap is that no law requires any ingredient to be identified as a microplastic. A brand listing "Polyethylene" is fully compliant, whether a consumer recognizes that as a plastic or not. This means that labels provide an incomplete picture for microplastic detection.
How ingredient labels work
Under 21 CFR § 701.3, cosmetics sold in the US must declare all ingredients in descending order of concentration. INCI names are mandatory; common names or marketing terms are not acceptable substitutes. A brand cannot list "plastic" or "microbeads" in place of the official name, and it cannot omit an ingredient because it appears in a small amount or serves a minor function.
The labeling system was designed to ensure full disclosure of chemical identity. It was not designed to convey physical form (e.g. whether an ingredient is present as a dissolved agent, a gel, or solid particles). But this distinction is central to identifying microplastics, as explained below.
The INCI names that indicate microplastics
The international nonprofit Beat the Microbead has catalogued 500+ synthetic polymer INCI names used in cosmetics globally. The names most commonly found in leave-on products and most likely to indicate solid plastic particles include:
| INCI Name | Common function in skincare |
|---|---|
| Polyethylene (PE) | Texture agent, film former |
| Polypropylene (PP) | Texture agent, film former |
| Polymethyl Methacrylate (PMMA) | Texture agent, skin-feel microspheres, opacifier |
| Nylon-12 | Texture agent, slip agent, powder |
| Nylon-6 | Texture agent, powder |
| Polyurethane-35 | Film former, fixative |
| Polymethylsilsesquioxane | Skin-feel microspheres |
| Polytetrafluoroethylene (PTFE) | Slip agent, texture |
A second category of ingredients has uncertain microplastic status because the same INCI name can describe either a dissolved polymer or solid particles depending on the formulation. Examples include Acrylates Copolymer, Carbomer, and various Polyquaternium compounds. Their status cannot be determined from the label alone.
The physical form problem
INCI names describe chemical composition, not physical form. "Polyethylene" on a label confirms the chemical is present; it does not confirm whether it is dissolved or in solid particle form. Only solid particles constitute microplastics. A brand listing "Polyethylene" provides exactly what the law requires, while a consumer reading the label correctly has no way to determine the particle status from that disclosure.
The INCI system was built to standardize chemical nomenclature across formulations and jurisdictions—conveying physical form was never part of its design. Lab testing is the only way to confirm whether a specific product contains microplastic particles at measurable concentrations.
What the label can't show
Checking INCI names addresses only intentionally added microplastic ingredients. A separate source of microplastic contamination (e.g., from plastic packaging, manufacturing equipment, and the production environment) doesn't appear on any label, because no US or EU regulation currently requires it to.
The Microbead-Free Waters Act (2015) banned intentionally added microbeads in rinse-off products (face wash, exfoliating scrubs). Leave-on products are explicitly excluded—moisturizers, night creams, and serums face no equivalent restriction, intentional ingredients or otherwise.
For more on how contamination enters products through packaging and manufacturing, see How Do Microplastics End Up in Your Moisturizer If They're Not Listed as Ingredients?. For a closer look at one packaging-specific pathway, the cap and seal, see Is Glass Skincare Packaging Actually Safer Than Plastic?.
What you can do with this
Checking an ingredient label for the INCI names above can tell you whether a brand intentionally added synthetic polymer microparticles to a formulation. It cannot tell you whether those particles are present in solid form, at what concentration, or whether the product contains additional contamination from packaging or manufacturing.
At KnowLabels, we test skincare products for microplastics, including contamination from packaging and manufacturing. Join our waitlist to learn more about what you are putting in your skin.
Frequently asked questions
If a product lists Polyethylene on its label, does that mean it contains microplastics?
Not necessarily. "Polyethylene" on a label confirms the chemical is present, but INCI names describe chemical composition, not physical form. The same name can refer to a dissolved film-forming agent or solid plastic particles—only the latter constitutes a microplastic. Lab testing is the only way to confirm which form is present in a specific product.
What INCI names should I look for to identify microplastics in moisturizers?
The most commonly found in leave-on products include Polyethylene, Polypropylene, Polymethyl Methacrylate (PMMA), Nylon-12, Nylon-6, Polyurethane-35, Polymethylsilsesquioxane, and Polytetrafluoroethylene (PTFE). A second category, including Acrylates Copolymer, may or may not be microplastics depending on the formulation; their status can't be confirmed from the label alone.
Are brands required to disclose that their products contain microplastics?
No. Brands are required to list every ingredient by INCI name, but no US law requires any ingredient to be identified as a microplastic. A product listing "Polyethylene" is fully compliant. There is no warning, flag, or microplastic designation required anywhere on a cosmetic label.
Did the microbead ban eliminate microplastics from skincare products?
No. The Microbead-Free Waters Act (2015) banned intentionally added plastic microbeads in rinse-off products (e.g., face wash, exfoliating scrubs, and similar products). It explicitly excluded leave-on products: moisturizers, night creams, and serums are not covered. The ban also doesn't address microplastics that enter products through packaging or manufacturing.
Can I tell from the ingredient list whether my moisturizer is microplastic-free?
Only partially. Checking for the INCI names listed above can tell you whether a brand intentionally added synthetic polymer microparticles. It can't confirm whether those particles are in solid form, at what concentration, or whether the product contains microplastic contamination from packaging or manufacturing. Lab testing is the only way to know.
Sources
- 21 CFR § 701.3 — Cosmetic ingredient declaration (FDA / eCFR) — eCFR / FDA overview
- Beat the Microbead — synthetic polymer INCI database — beatthemicrobead.org
- Microbead-Free Waters Act of 2015 (FDA FAQs) — FDA / Congress.gov