The 4 most promising plastic alternatives

By Ushma Pandya Mehta

Every conversation about sustainable materials inevitably ends up turning into a conversation about how to get rid of plastic. 

It’s not hard to see why. Plastic waste is arguably the most pressing issue for waste reduction advocates, with 20 million tons of plastic waste entering the environment every single year. Plastic waste disrputs everything from human fertility (via microplastics) to marine biodiversity. Something must be done, advocates agree. But what?

It’s not enough to reduce our plastic use on an individual level, considering that 450 million tons of plastic are produced annually. Instead, manufacturers need to start implementing workable material alternatives. In the last decade, a number of viable options have emerged, making the possibility of reducing our dependence on petroleum-based plastics feel actually within reach. Here are four of the most 

1. PHA bioplastics (polyhydroxyalkanoates)

Bioplastics are fascinating. Unlike petroleum-based plastics, bioplastics are derived from biomass and biodegrade naturally in soil and water. Of the various kinds of bioplastics, PHA is a bit of a scientific marvel. It’s made by feeding microbes crops or waste produce. During the fermentation process, these microbes naturally produce a natural polymer as an energy reserve, which is subsequently harvested and purified. PHA can then be molded much the same way as petroleum-based plastics.

Key uses: Food packaging, disposable cutlery, agricultural films, textile fibers

2. Cellulose

Cellulose is the main structural component of plants, which means it’s also the most abundant polymer on the planet. With that kind of naturally-occuring supply, it’s no wonder scientists have turned to it as a potential plastic alternative. Cellulose can be synthesized into a bioplastic (like PHA) that degrades in salt water without shedding microplastics, and making it doesn’t even require new plants. Agricultural waste is among the most viable raw material sources for cellulose-based plastic, arguably putting another loop into the circular economy.

Key uses: Transparent films and moldable packaging, coatings, lightweight structural materials  

3. Fungus

Cellulose isn’t the only naturally abundant source for a plastic alternative. Mycelium composites are grown from fungal root networks and agricultural waste. They’re also among the least energy-intensive bioplastics to produce. Different fungal strains produce different composites with distinct properties: Reishi forms a strong and hydrophobic mat useful for packaging, oyster mushrooms produce a spongy composite that’s great for absorbent applications, and turkey tail mushrooms can be turned into pulp and paper. It’s fungal biodiversity reimagined in bioplastic form.

Key uses: Packaging foam, insulation, leather alternatives, building materials

4. Algae and seaweed

Seaweed farm

Marine-based sources of bioplastics are already starting to pull their weight. Spirulina powder can be molded into a strong and stiff bioplastic that’s fully biodegradable and may even be carbon negative, since spirulina cells sequester carbon dioxide. Seaweed and algae can be both wild-harvested and farmed—often without the use of fertilizers. Industrial production technology for these bioplastics is far enough along that they’re being commercialized by startups like Notpla and Sway.

Key uses: Food packaging, edible films, disposable sachets, agricultural materials

No single material is likely to replace conventional plastic entirely, but the growing variety of available alternatives feels undeniably promising. Bioplastics and other biodegradable composites are becoming more practical and cost-effective every year. Used together and at scale, PHA, cellulose, fungi, and algae could be key to fixing our 450 million ton production problem. 

Plastic Alternatives At-a-Glance

🌿 Material	🧰 Common Uses	✅ Pros	⚠️ Cons	🏭 Key Innovators	🛍️ Real-World Use	💰 Cost & Scalability
PHA Bioplastics	🍴 Cutlery 📦 Food packaging 🌾 Ag films 🧵 Fibers	Fully biodegradable (soil + ocean) Made from waste feedstocks No microplastics	Higher cost than plastic Limited global production capacity	Danimer Scientific RWDC  Industries Newlight	Nestlé (R&D) Bacardi bottles	💰 High cost today 📈 Scaling improving with investment, but still early-stage
Cellulose-Based	📄 Films 📦 Packaging 🛡️ Coatings 🏗️ Light materials	Abundant resource Marine biodegradable Uses ag waste streams	Sensitive to moisture Complex processing	Futamura Stora Enso NatureWorks	Food packaging films Retail packaging	💰 Moderate cost 📈 More scalable due to existing supply chains
Fungal (Mycelium)	📦 Packaging foam 🏠 Insulation 👟 Leather alt 🧱 Building panels	Very low energy production Compostable Upcycles waste	Durability varies Still niche manufacturing	Ecovative MycoWorks Bolt Threads	IKEA packaging Hermès leather Dell shipping	💰 Moderate–high 📈 Scaling steadily, strong VC backing
Algae & Seaweed	🍬 Edible films 📦 Packaging 💧 Sachets 🌱 Ag inputs	Carbon-sequestering No land/fertilizer needed Fully biodegradable	Short shelf life Limited durability	Notpla Sway Loliware	Just Eat packaging Event sachets	💰 Moderate–high 📈 Rapid innovation, scaling quickly in packaging niche