What Does Plastic-Free Packaging Actually Mean? The Truth

If you've looked at an aluminum can and assumed it was plastic-free, you're in good company. Most people do. The truth is more complicated: nearly every beverage can on the market has a polymer coating on the inside, and that metal cap on your glass bottle probably has a plastisol liner sealing it shut. Before you put "plastic-free" on your label, here is what the claim actually requires, where hidden plastics show up in formats you would never expect, and what genuinely plastic-free alternatives are available right now.

What "Plastic-Free" Actually Means (and What the Regulators Say)

In the United States, the FTC's Green Guides govern environmental claims including "free-of" statements. The standard is strict: a claim that packaging is "plastic-free" must be substantiated and cannot be misleading. If any component contains plastic, an unqualified "plastic-free" claim can trigger enforcement action.

In the European Union, the Single-Use Plastics Directive defines plastic as "a material consisting of a polymer to which additives or other substances may have been added," but explicitly excludes "natural polymers that have not been chemically modified." That exclusion has opened the door for materials like unmodified seaweed coatings to be classified as plastic-free in EU markets.

The practical reality: plastic-free packaging claims are not federally standardized in the U.S., the EU definition hinges on whether a polymer has been chemically modified, and enforcement is increasing as regulators crack down on greenwashing. Our post on greenwashing explained covers the regulatory risk of overstating environmental claims in more detail.

The Hidden Plastics in Packaging You Think Is Plastic-Free

Three categories of packaging are routinely assumed to be plastic-free by consumers and occasionally by the brands using them. All three typically contain polymers that complicate or disqualify an absolute plastic-free claim.

Aluminum Cans

Nearly all aluminum beverage cans are lined with a thin polymer coating, most commonly an epoxy resin or a similar formulation, applied to the interior surface. According to the Food Packaging Forum, these polymer coatings prevent the aluminum from corroding when in contact with acidic or carbonated beverages, protect flavor integrity, and allow the can to withstand pasteurization or hot-fill processes.

The coatings industry has made real progress in recent years. Many can manufacturers have transitioned away from bisphenol A (BPA)-based epoxies to BPA-non-intent formulations, and the European Commission recently adopted a ban on BPA in all food-contact materials effective in stages beginning early 2025. This is currently a European regulation, not a U.S. federal requirement, but brands selling into EU markets need to comply now, and U.S. brands sourcing globally should be aware that shipments containing non-compliant materials can be rejected at the border. A BPA-free coating is still a polymer coating. The aluminum can itself may be infinitely recyclable, but calling the package plastic-free would be misleading under FTC standards.

Plastisol Liners in Metal Caps

Metal twist-off caps and lug caps (the kind you find on glass bottles of juice, pasta sauce, or beer) almost always contain a plastic liner on the underside of the closure. These liners, often made from plastisol (a PVC-based compound), create the airtight seal and vacuum retention necessary for shelf stability and carbonation. Some closures now use alternative liner materials (polyethylene-based or other thermoplastics) to avoid PVC, but the liner itself remains polymeric.

For a brand printing "plastic-free" on a glass bottle with a metal cap, the cap liner is a compliance risk. The container may be glass, the closure may be steel or aluminum, but that liner is plastic and it touches the product.

Adhesives and Glues

Even when the substrate and coating are genuinely plastic-free, the adhesive holding box seams, label laminates, or packaging closures together is often a synthetic polymer. EVA (ethylene vinyl acetate) and other hot-melt glues are the most common culprits. A paperboard box with a seaweed-based barrier coating and a synthetic hot-melt seam adhesive cannot carry an unqualified "plastic-free" claim under FTC standards. Ask your supplier for adhesive disclosure alongside substrate and coating documentation.

Compostable Packaging

Not always plastic-free. Many industrially compostable films and bags contain fossil-based biodegradable polymers. The most common example is PBAT (polybutylene adipate terephthalate), a petrochemical-derived polyester that is certified compostable under ASTM D6400 and EN 13432 standards but is decidedly not bio-based.

European Bioplastics notes that compostability and bio-based content are independent attributes. A resin can be fossil-derived and still break down completely in an industrial composting facility. PBAT is frequently blended with PLA (polylactic acid, which is bio-based) to improve flexibility and performance, but the resulting film is a mix of plant-derived and petroleum-derived polymers.

One more distinction worth making explicit: being bio-based does not mean a material is plastic-free. Plant-based polyethylene (Bio-PE) and plant-based PET (Bio-PET) are made from sugarcane or other renewable feedstocks, but they are chemically identical to their petroleum-derived equivalents. Bio-PE is still polyethylene. A package made from sugarcane plastic cannot carry a plastic-free claim. The source of the carbon atoms does not change the polymer chemistry, its recyclability, or its classification under FTC or EU rules. If your brand's goal is to eliminate petroleum-based polymers entirely, verify not just compostability certification but also the bio-based content percentage of the resin. Our post on are compostable packaging claims actually legit covers what the certifications do and do not verify.

Why Plastic-Free Packaging Matters

The push toward plastic-free formats is driven by two parallel concerns: human health and environmental pollution. Both have strengthened significantly in recent years as new research has clarified risks that were previously theoretical.

Microplastics and Nanoplastics: The Health Evidence

In early 2024, researchers using advanced stimulated Raman scattering microscopy detected an average of 240,000 micro- and nanoplastic particles per liter in bottled water samples. According to the National Institutes of Health, about 90% of those particles were nanoplastics, small enough to cross biological barriers that larger microplastics cannot.

That same year, a prospective cohort study published in the New England Journal of Medicine followed 257 patients who underwent carotid artery plaque removal. Researchers found that patients whose plaques contained detectable micro- and nanoplastics had a significantly higher risk of myocardial infarction, stroke, or death over a mean follow-up of 33.7 months compared to patients whose plaques did not. This is observational data, not proof of causation, but it is the first human evidence linking tissue-level plastic contamination to adverse cardiovascular events.

Environmental Scale

Packaging is the largest single-use category of plastic production globally. The OECD projects that without stronger policy intervention, global plastic waste will nearly triple by 2060, and lifecycle greenhouse gas emissions from plastics could more than double to approximately 4.3 gigatons of CO2 equivalent annually. Shifting to formats that contain no synthetic polymers addresses both the litter problem and the carbon intensity of virgin plastic production.

Does Plastic-Free Mean Easier to Recycle?

Sometimes. A packaging format that contains no plastic can be easier to recycle if it is mono-material and compatible with existing infrastructure. Uncoated fiber is straightforward to repulp. But plastic-free does not automatically mean recyclable. A paperboard tray coated with a seaweed-based barrier may be plastic-free under EU rules, but if that coating interferes with fiber recovery during repulping, it is not recyclable in practice. The American Forest and Paper Association's Design Guidance provides thresholds for coatings and additives that paper-based packaging must meet to be considered recyclable by paper mills. The key technical term here is repulpability: a coating must break down into particles small enough to pass through mill screens during the pulping process. If it does not, it becomes screen rejects, material that gets separated out and sent to landfill regardless of how well-intentioned the packaging design was. Plastic-free and repulpable are two separate attributes, and you need both for a paper-based package to complete the recycling loop. Our guide to whether your packaging is actually recyclable covers the infrastructure reality behind these claims.

Genuinely Plastic-Free Barrier Coatings That Actually Exist

The technical challenge that has kept polymers entrenched in packaging is barrier performance. Plastics are extremely good at blocking oxygen, water vapor, and grease. For decades, no other material class could match that performance at comparable cost and scale. That is changing.

Seaweed-Based Coatings

Notpla, a UK-based material science company, has developed a seaweed-derived coating for fiber-based foodservice packaging. In early 2024, the Dutch government's Human Environment and Transport Inspectorate recognized Notpla's coating as the first material verified as plastic-free under the EU Single-Use Plastics Directive. Because seaweed-derived polymers fall under the SUPD exemption for "natural polymers not chemically modified," the Dutch authority classified the finished packaging as non-plastic. That regulatory precedent matters for brands operating in EU markets where single-use plastic bans are in force.

Cellulose Nanocrystal and Nanofiber Barriers

Cellulose-based barrier coatings use nano-scale plant fibers to create a dense, organized film that resists water vapor, oxygen, and oil. Companies like Melodea offer cellulose-based water vapor barriers that can be applied on standard coating lines and are designed to be repulpable in paper recycling systems. These coatings are free of PFAS, BPA, and synthetic polymers, with performance data showing transmission rates competitive with low-density polyethylene coatings for many applications. The technology is commercially available today in foodservice packaging, dry-food cartons, and some flexible applications.

Inorganic Barrier Films

Silicon oxide (SiOx) and aluminum oxide (AlOx) coatings are ultra-thin inorganic films deposited onto paper or other substrates via vacuum deposition. These barriers provide high oxygen and moisture resistance and contain no organic polymers. SiOx coatings are widely used in Europe on paper-based packaging for dry foods like coffee and snacks, and the coating is thin enough that it does not interfere with paper recyclability in many systems.

What to Verify Before Making a Plastic-Free Claim

Request a full material disclosure. Ask for a breakdown of every component: substrate, coating, adhesive, ink, and closure. Verify that none contain synthetic polymers. If a supplier says a coating is "plant-based," ask whether it has been chemically modified and whether it contains any fossil-derived biodegradable polymers like PBAT or PCL. Material disclosure is not standard practice in packaging sales, but if a supplier cannot or will not provide it, that is a red flag.

Confirm regulatory definitions for your market. A material that qualifies as plastic-free under the EU's SUPD interpretation may not meet the FTC's substantiation standard in the U.S. If you operate in multiple markets, align your claim language to the most conservative standard or qualify the claim by jurisdiction. For U.S. markets, assume the FTC will evaluate the claim based on consumer understanding and the presence of any polymeric material, synthetic or otherwise.

Test recyclability and compostability separately. Plastic-free does not guarantee recyclability. If you plan to print recycling instructions or a How2Recycle label, submit samples to the relevant certification program or test against AF&PA design guidance thresholds for repulpability. If the packaging is compostable, verify certification to ASTM D6400 or EN 13432 and confirm access to composting infrastructure in your target markets.

Watch for chemical substitution risks. As you move away from plastic, verify that replacement coatings and barriers are not introducing new risks. EFSA lowered the tolerable daily intake for BPA to 0.2 nanograms per kilogram of body weight per day in 2023. Ask for food-contact compliance documentation, migration test data, and confirmation that coatings are free of PFAS, BPA, and phthalates. Our post on PFAS in packaging covers the regulatory history and what compliance requires.

The Bottom Line

Plastic-free packaging exists, and the technology is improving rapidly. But much of what consumers and brands assume is plastic-free today actually contains polymers in coatings, liners, adhesives, or resin blends. Aluminum cans have polymer linings. Metal caps have plastisol or thermoplastic gaskets. Many compostable films contain fossil-based PBAT. These are not secrets, but they are not prominently disclosed either, and an unqualified "plastic-free" claim on any of these formats would likely fail regulatory scrutiny.

The better news is that genuinely plastic-free barrier technologies are now commercially available. Seaweed coatings, cellulose nanocrystal films, and inorganic oxide barriers are being used at scale in Europe and entering North American markets. They cost more than plastic and are not suited to every application, but they work. If your brand is pursuing plastic-free packaging, the path forward is specificity. Verify every material component. Align claims to the regulatory standards in your market. Test end-of-life performance rather than assume it.

Our plastic-free packaging page covers the supplier landscape for formats that can credibly support a plastic-free claim, along with the questions worth asking before committing. And our guide to what packaging certifications actually mean covers how to verify the claims your supplier is making.

Sustainable packaging can be complicated, but we are here to change that. If you already know what you need, our free search tool gets you there fast. If you want to explore what's out there, our sustainable packaging suppliers directory covers companies across every format and category. And if you'd rather have us help you find the right fit, get in touch and we'll point you in the right direction.