Real-world examples of challenges and limitations of biodegradable plastics

If you want the best examples of challenges and limitations of biodegradable plastics, start with everyday products people actually use: coffee cups, grocery bags, takeout containers, and utensils. These are the things that were supposed to “disappear,” yet often end up sticking around.

A classic example of this disconnect is compostable coffee cups and lids. Many are made from PLA (polylactic acid), a bioplastic derived from corn. On paper, PLA sounds great. In practice, the limitations show up fast:

• PLA cups typically require industrial composting conditions—sustained high temperatures, controlled moisture, and active aeration—to break down in a reasonable time. Most backyard compost piles never reach those conditions, so the cups can sit there for months or years.
• In landfills, where oxygen is limited, PLA breaks down very slowly, if at all. Instead of biodegrading, it behaves a lot like conventional plastic. Research published via the U.S. Environmental Protection Agency (EPA) has repeatedly pointed out that landfill conditions are not designed to promote biodegradation of any material, including bioplastics.

Real examples include city programs that tried switching to compostable food packaging for events, only to find that local compost facilities refused the material. The result? “Compostable” cups and utensils were diverted to landfills because the regional system wasn’t set up to handle them.

Another example of limitations comes from so‑called biodegradable shopping bags. In some U.S. cities, retailers adopted bags labeled “biodegradable” or “oxo-biodegradable.” These bags can fragment into smaller pieces under heat and UV exposure, but that doesn’t mean they fully mineralize into carbon dioxide, water, and biomass. Instead, they can turn into microplastic-like fragments that persist in soil and waterways. This is one of the clearest examples of challenges and limitations of biodegradable plastics: products that sound better but still contribute to long-term pollution.

How waste systems expose the limitations: infrastructure as a real-world example

If you’re looking for a powerful example of why biodegradable plastics underperform, look at the mismatch between product design and waste infrastructure.

Industrial composting facilities in the U.S. and Europe operate under tight contamination limits. Many of them only accept yard waste and food scraps, not packaging. When compostable plastics do show up, they can cause operational headaches:

• Compostable forks and cups can take longer to break down than food scraps during the standard composting cycle.
• Facilities may have to screen out partially degraded plastics and landfill them, adding cost and defeating the purpose.

In 2023–2024, several municipal compost programs publicly reported problems with compostable packaging contamination. Some facilities in the U.S. and Canada explicitly stopped accepting compostable plastics because they were too hard to distinguish from conventional plastics at scale. This is one of the best examples of challenges and limitations of biodegradable plastics: even when the material can technically biodegrade, the real-world system can’t reliably separate, process, or verify it.

Recycling systems offer another strong example of limitations. PLA and other bioplastics are not compatible with standard PET recycling streams. A small percentage of PLA mixed with PET bottles can degrade the quality of recycled plastic. Because optical sorters can’t always distinguish bioplastics from conventional plastics, compostable packaging can contaminate recycling bales. The Association of Plastic Recyclers (APR) has issued guidance warning that compostable and biodegradable plastics should be kept out of recycling streams for this reason.

These system-level examples of examples of challenges and limitations of biodegradable plastics show that material science alone doesn’t solve anything if collection and processing systems aren’t aligned.

Environmental performance: examples include slow breakdown and microplastic risks

Another important example of limitations is how biodegradable plastics behave in uncontrolled environments—oceans, rivers, roadside ditches, and soil.

Many consumers assume “biodegradable” means “this will vanish quickly anywhere.” That’s not how it works. Standards like ASTM D6400 (for compostable plastics) specify conditions that are very different from what you find in the ocean or in cold soil. Under marine conditions, even certified compostable plastics can persist for long periods.

A widely cited study published through organizations like the National Oceanic and Atmospheric Administration (NOAA) and other marine research groups has found that so‑called biodegradable bags and films can remain intact in seawater for months or longer. Some might fragment, but that does not necessarily mean full biodegradation. This is a sobering example of examples of challenges and limitations of biodegradable plastics: performance claims are often tied to lab or industrial conditions, not the environments where plastic pollution actually causes the most harm.

There’s also the microplastic issue. Oxo-degradable and some starch-blend plastics can break into tiny pieces under sunlight and mechanical stress. If the additives or environmental conditions are not right for full biodegradation, those fragments can behave like microplastics—entering food webs and potentially affecting wildlife. While ongoing research, including work summarized by the U.S. National Institutes of Health (NIH), is still clarifying health impacts of microplastics, the environmental concern is already clear.

So when people ask for an example of why biodegradable plastics aren’t a silver bullet for ocean pollution, the persistence of certified compostable bags and utensils in marine and freshwater environments is one of the starkest answers.

Marketing, labeling, and greenwashing: examples of confusion and misleading claims

If you want real examples of challenges and limitations of biodegradable plastics from the consumer side, look at the labels.

Terms like “biodegradable,” “compostable,” “oxo-biodegradable,” “bio-based,” and “plant-based” are often used interchangeably in marketing, even though they mean very different things. This has triggered regulatory responses:

• The U.S. Federal Trade Commission (FTC) Green Guides warn companies against making unqualified “biodegradable” claims, especially if a product is likely to end up in a landfill, incinerator, or recycling facility where it will not biodegrade in a short time frame.
• California and several other states have restricted the use of the word “biodegradable” on plastic products unless they meet strict standards.

Real examples include class-action lawsuits against brands that marketed plastic bags, bottles, or cutlery as biodegradable when there was no credible evidence they would fully break down in normal disposal environments. These cases highlight another example of limitations: even when the technology is promising, sloppy or misleading marketing can backfire, eroding public trust.

Labeling confusion also drives wrong-bin disposal. Consumers see “compostable” and toss the item into recycling, or they see “biodegradable” and assume they can litter it. Surveys in the U.S. and Europe have shown that many people interpret biodegradable labels as a license to worry less about proper disposal. This behavioral effect is a subtle but very real example of challenges and limitations of biodegradable plastics.

For more on misleading environmental claims, the FTC Green Guides are a good reference point:

• https://www.ftc.gov/news-events/topics/truth-advertising/green-guides

Economic and supply chain examples of limitations

The economics behind biodegradable plastics provide another set of examples of challenges and limitations of biodegradable plastics that rarely make it onto product labels.

Bio-based and biodegradable plastics often cost more to produce than conventional polyethylene or PET, especially when oil prices are low. This cost gap can limit adoption in price-sensitive markets like food packaging. Many smaller brands discover that switching to certified compostable packaging significantly raises their packaging budget, which can be a deal-breaker.

Then there’s the feedstock issue. A large share of commercially available biodegradable plastics, like PLA, are made from corn, sugarcane, or other agricultural crops. This raises questions about land use, fertilizer use, and competition with food production. Organizations such as the Food and Agriculture Organization (FAO) and various academic groups have pointed out that large-scale expansion of bio-based plastics could intensify pressure on agricultural land if not managed carefully.

A concrete example: in the early 2020s, several global brands experimented with high levels of bio-based plastics in their packaging. They later scaled back or rebalanced their strategies, citing supply chain volatility, cost, and concerns about indirect land-use impacts. This is a clear example of limitations: even if the material works technically, the broader system—farms, prices, climate impacts—may not support infinite scaling.

Performance trade-offs: durability, shelf life, and product safety

Biodegradable plastics are often optimized to break down under certain conditions. That can come with trade-offs in durability and shelf life. These trade-offs are another practical example of challenges and limitations of biodegradable plastics.

Food packaging is a good case. Many biodegradable films have lower barrier properties against oxygen and moisture compared with conventional plastics. That can shorten shelf life for snacks, coffee, or fresh produce. If food spoils faster, you can end up with more food waste—a major climate issue in its own right, as documented by the U.S. Department of Agriculture (USDA) and the EPA.

Real examples include:

• Early generations of compostable chip bags that were noisy, brittle, and had shorter shelf life than standard bags. Some brands faced consumer backlash and quietly dropped or reformulated those packages.
• Biodegradable utensils that soften or warp in hot liquids. Cafés and restaurants reported customer complaints about forks bending in hot soup or spoons deforming in coffee.

These performance issues illustrate a key example of limitations: in trying to design plastics that will eventually break down, manufacturers sometimes compromise the properties that made plastics so useful in the first place.

Policy and standards: examples of progress and ongoing limitations

On the policy side, there are promising moves—but they also highlight examples of limitations.

Standards like ASTM D6400 (U.S.) and EN 13432 (EU) define criteria for compostability, including biodegradation rates and disintegration in industrial composting. Certification bodies test products against these standards, which is a step forward. However, there are still gaps:

• Most standards focus on industrial composting, not home composting, landfills, or marine environments.
• Certification logos can be small, confusing, or mixed with marketing symbols, so consumers still struggle to understand what to do with the product.

A good example of this tension is the rise of “OK compost HOME” and similar labels, which try to signal that a product can break down in backyard compost. Yet real-world tests show that many home compost setups vary wildly in temperature and moisture, so results are inconsistent.

Policymakers are also starting to question where biodegradable plastics actually add value. The European Commission and some U.S. cities have issued guidance suggesting that biodegradable or compostable plastics should be targeted to specific applications—like food-soiled packaging in regions with strong composting infrastructure—rather than used as a blanket replacement for all plastics. That guidance itself is an example of challenges and limitations of biodegradable plastics: regulators are acknowledging that the technology has a narrow sweet spot.

For more technical background on biodegradation standards and testing, see:

• https://www.epa.gov/smm/sustainable-management-materials-non-hazardous-materials-and-waste-management-hierarchy

So when do biodegradable plastics actually make sense?

After walking through these real examples of examples of challenges and limitations of biodegradable plastics, it’s fair to ask: are they ever worth it?

They can be—in very specific contexts. Some of the best examples of sensible use include:

• Food service items in cities with well-developed industrial composting and clear labeling rules, where food scraps and compostable packaging are collected together.
• Agricultural mulch films designed to biodegrade in soil under controlled conditions, reducing labor needed to retrieve films at the end of the season—provided they meet rigorous soil safety tests.

Even in these cases, success depends on matching the material, the product, and the local waste system. That’s the big lesson running through all these examples of challenges and limitations of biodegradable plastics: the material alone doesn’t solve anything. You need infrastructure, policy, clear communication, and realistic expectations.

FAQ: real examples of challenges and limitations of biodegradable plastics

Q1: What are some real examples of biodegradable plastics not breaking down as expected?
A common example of this problem is PLA coffee cups and utensils that end up in landfills or backyard compost. Without the high temperatures and controlled conditions of industrial composting, they can remain intact for long periods. Another real example is biodegradable shopping bags that fragment into small pieces but do not fully biodegrade in soil or marine environments.

Q2: Can you give an example of how biodegradable plastics interfere with recycling?
Yes. PLA bottles or clamshells mixed into PET recycling streams can lower the quality of recycled plastic. Sorting equipment can struggle to distinguish them, so even a small amount of PLA can contaminate a batch of PET, leading recyclers to reject or downgrade the material.

Q3: Are there examples of biodegradable plastics contributing to microplastic pollution?
Some oxo-degradable plastics and certain blends can break into tiny fragments under sunlight and mechanical stress. If they do not fully biodegrade, these fragments behave similarly to microplastics. Studies summarized by agencies like NOAA and research institutions have documented persistence of these fragments in marine and terrestrial environments.

Q4: What is an example of regulations responding to the limitations of biodegradable plastics?
California law restricts the use of the term “biodegradable” on plastic products unless they meet specific standards, and the FTC Green Guides warn against vague biodegradability claims. These policies are direct responses to misleading marketing and confusion around biodegradable plastics.

Q5: Are there examples of biodegradable plastics working well?
Yes, but they are context-dependent. One positive example is compostable foodware used in closed venues—like stadiums or corporate campuses—where all waste is collected and sent to a partner industrial compost facility that accepts and properly processes certified compostable items. In those controlled systems, biodegradable plastics can help divert food-contaminated material from landfills.