Five Natural Plastic Alternatives Actually Moving the Industry Forward

After fifteen years of pulling plastic out of rivers, we're paying close attention to the materials engineered to never end up there.

Since 2010, we've helped remove over five million pounds of trash from waterways. The same items show up again and again: plastic bottles, food wrappers, fishing gear, cigarette filters, mystery fragments that used to be something. After a while you stop seeing trash and start seeing materials — and the question becomes less “how do we stop the litter?” and more “what could we have used instead?”

Most “eco” packaging we've seen over the years lands somewhere between greenwashing and good-intentions-no-data. But the last few years have produced a small group of materials that actually do what they claim. They biodegrade in months, not centuries. They came from the ocean or from the soil, and they go back to it. They're being used at scale by real brands, with real shipments, in real cities.

Here are five we're tracking — what they replace, where they are now, and why each one matters.

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1. Sway — Seaweed-based polybags

Replaces: LDPE polybags, mailers, and shipping films.

If you've ever ordered a t-shirt or socks online, your order almost certainly arrived in a low-density polyethylene (LDPE) polybag. The apparel industry alone is estimated to use roughly 180 billion of them every year^[1] — most ending up in landfill or, eventually, in the rivers we clean up. Sway makes bags from regeneratively farmed seaweed, plants, and compostable polymers that run on the same equipment as conventional polybags, look and feel nearly identical, and home-compost in months^[2].

Sway was named one of TIME's Best Inventions of 2025 for their TPSea Flex™ material^[3], and they're already in market with Dr. Bronner's, Faherty, and other brands we recognize. What makes this one unusually credible from a brand-operations standpoint is that Sway didn't ask the industry to retool — they engineered a drop-in. The only swap that scales is the one that doesn't ask people to change.

2. Notpla — Edible and dissolvable seaweed packaging

Replaces: single-use plastic sachets, takeaway containers, and food-grade films.

Notpla, a London-based company spun out of Imperial College, builds materials from brown seaweed that biodegrade in weeks rather than years — and in some forms, you can eat them. Their Ooho edible water capsules went viral after 36,000 of them replaced plastic bottles at the London Marathon, with no waste left behind^[4]. They've since expanded into takeaway boxes, sachets, and film coatings used by Just Eat across thousands of UK orders^[5].

What's interesting from a clean-up perspective: most of the plastic we collect in waterways is fragmented food packaging. A material that disappears safely in water if it ever escapes the supply chain isn't just better at end-of-life — it's a different category of risk altogether.

3. Ecovative / Mushroom Packaging — Mycelium

Replaces: expanded polystyrene (EPS) foam used to protect electronics, furniture, glassware.

EPS foam is one of the most persistent — and most useless — materials we encounter on cleanups. It crumbles into thousands of tiny white spheres that look exactly like fish eggs, which is exactly the problem. Ecovative grows protective packaging from mycelium (the root structure of fungi) bonded with agricultural waste. The end product is rigid, shock-absorbing, and home-compostable in roughly 45 days^[6].

This isn't a new idea trying to find a market — Mushroom Packaging has been in commercial use for over a decade. IKEA publicly committed to mycelium packaging in 2016, and Dell has used it for shipping protection since 2011^[7]. Their newer lines extend into insulation panels and even fashion (Hermès released the Victoria travel bag in mycelium-leather in 2021^[8]). Of all the materials on this list, mycelium has the deepest commercial track record.

4. Kelpi — Marine-safe bioplastic films

Replaces: laminated films, sachets, and cosmetic packaging.

Kelpi is a UK biotech turning seaweed into compostable bioplastic films^[9]. It's earlier-stage than Notpla — much of their work right now is in cosmetics packaging — but the angle is one we care about: their films are designed to dissolve safely in seawater without leaving microplastics behind. Most “biodegradable” plastics on the market today still need industrial composting heat to actually break down. Kelpi's are built around the assumption that some percentage of any packaging will end up where it shouldn't, so the material has to behave responsibly when it does.

5. GROWN bio — Mycelium for packaging and interiors

Replaces: EPS foam, MDF panels, and synthetic-foam interior elements.

GROWN, based in the Netherlands, takes the same mycelium approach as Ecovative and extends it deeper into industrial design — interior panels, acoustic tiles, lampshades, and packaging molds for designers and small-batch brands^[10]. The team grew out of the Officina Corpuscoli bio-design studio, so the work tends to look polished rather than experimental. We mention them separately from Ecovative because they're a useful reminder that mycelium isn't just a foam-replacement; it's a class of materials that can replace a much wider slice of what's currently petroleum-derived.

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What we're doing about it

The honest answer: we're tracking each of these, and we've started conversations with EcoEnclose, a company working on packaging solutions with Sway, about piloting their seaweed polybags in our shipping. None of these materials solves the problem alone — packaging is only one slice of the plastic problem, and supply-chain trade-offs (cost, performance, freight, certifications) are real. But after fifteen years of pulling the same plastics out of the same rivers, watching real alternatives reach the market is the most encouraging thing we've seen in a long time.

The cleanups don't stop. We'll keep showing up. But we're also paying attention to the people working at the front of the supply chain — because the trash we don't pick up next year is the packaging that gets re-engineered this year.

If you're a brand exploring any of these materials, we'd love to compare notes. And if you want to be part of the cleanup side, find an upcoming event.

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Sources

1. Fashion for Good — Circular Polybag Pilot (figure cited in Sourcing Journal: “the fashion supply chain uses roughly 180 billion virgin polybags each year”). sourcingjournal.com
2. Sway — Materials & compostability. swaythefuture.com
3. TIME, Best Inventions of 2025: Sway TPSea Flex™. time.com
4. Dezeen — Seaweed Ooho drink capsules replace plastic bottles at London Marathon (29 April 2019). dezeen.com. Notpla / Lucozade Sport materials cite 36,000 capsules distributed.
5. Just Eat × Notpla — UK seaweed-lined takeaway box rollout. notpla.com/projects
6. Ecovative — Mushroom Packaging compostability data. ecovative.com
7. Dell — Mushroom Packaging at Dell (sustainability disclosures, 2011 onward).
8. Hermès × MycoWorks — Victoria travel bag in Sylvania, AW 2021 release. dezeen.com
9. Kelpi — Technology / seaweed bioplastic films. kelpi.com
10. GROWN bio. grown.bio

Hero photo: Greg Rosenke / Unsplash.