Consumers want to make more sustainable choices, but many struggle to understand what “bio-based”, “biodegradable”, and “compostable” actually mean—largely because the language used by industry and policymakers doesn’t match how people process information in real life. That’s the central finding of a new report from BB-REG-NET, the UK’s regulatory science network for bio-based and biodegradable materials, authored by Professor Joanna Gavins of the University of Sheffield.

In the report, Effective Communication to Advance the Modern Industrial Bioeconomy, researchers describe this problem as “hypocognition”—a concept from cognitive linguistics where people lack the mental framework to interpret unfamiliar terminology. Without consistent, repeatable labelling and disposal systems, the public has limited opportunity to build understanding through everyday experience.

“Consumers want to make more sustainable choices, but they're overwhelmed by confusing language and greenwashing,” Gavins said, arguing that clear communication is now a key enabler of the modern bioeconomy.

Why the terms don’t land with the public

The report combines linguistic analysis with consumer research to show just how far these terms are from everyday language. Using Oxford English Dictionary (OED) frequency banding and a 52-billion-word corpus of contemporary English texts, the study found that these words remain rare in general use:

• “Biodegradable”: 1.51 occurrences per million words
• “Compostable”: 0.53
• “Bio-based”: 0.23
• “Bioplastic”: 0.13

By comparison, common everyday vocabulary typically appears 100–1,000 times per million words. Under OED frequency banding, only “biodegradable” reaches Band 5, meaning it is recognisable but still “distinctively erudite” and associated with educated discourse. The remaining terms fall into more specialist bands and are often “strange or exotic” to general audiences.

Further analysis using the enTenTen21 corpus and Sketch Engine showed that these key bioeconomy terms largely appear in specialist contexts—science, health, business, and economics—rather than in everyday domains such as the home, family life, beauty and fashion, or even broader environmental discussion. The report argues this helps explain why consumers encounter the terms on packaging but rarely see them reinforced in daily conversation, media, or routine behaviour.

Recyclable is different—and the report explains why

The report contrasts these findings with “recyclable” (1.57 occurrences per million words), which appears across many domains including household content, lifestyle topics, news, technology, and environmental writing. The difference, the report argues, is that recycling has benefited from decades of consistent infrastructure, legislation, and behavioural repetition, making both the language and the process familiar.

Linguistic ‘traps’ that drive misunderstanding

The report identifies specific language patterns that create confusion:

• The “-able” suffix (biodegradable/compostable) forces consumers to imagine a future state, rather than giving an actionable instruction about what to do now. It often fails to communicate the conditions or timeframe required for the product to break down.
• The “bio-” prefix is used inconsistently. In “bio-based” it refers to biological origin (renewable sources), while in “biodegradable” it refers to a biological process (microbial breakdown). Consumers often merge these meanings and assume that anything “bio-” will decompose naturally.

That confusion shows up in behaviour. In a BB-REG-NET survey of 2,000+ UK consumers, while 51% trusted compostability claims, only 22% said they knew what happens to waste after collection. Focus groups in October 2025 found many participants would put packaging labelled “compostable” in home garden compost, and assumed “bio-based” products would break down in the natural environment.

A practical framework: define terms, then give instructions people will follow

The report proposes a communications framework built around two needs: providing information and giving instruction.

1) Standardise definitions

To reduce confusion and limit greenwashing, the report recommends consistent definitions used across the value chain:

• Bio-based: materials derived wholly or partly from renewable biological sources.
• Biodegradable: materials designed to break down through microbial activity under specific conditions; claims should specify the conditions and timeframes.
• Compostable: a subset of biodegradable materials that meet recognised standards; communications should clarify whether home composting or industrial composting is required.

The report also flags “bioplastic” as especially confusing and recommends avoiding it.

2) Make disposal instructions explicit and behaviourally informed

When it comes to disposal, the report found that negatively framed instructions can be clearer than positive alternatives. In focus groups, “do not place in recycling bin” was rated the clearest instruction by all but one participant, followed by “not recyclable”. The report explains this through cognitive linguistic theory: negation can foreground attention, break expectations, and reduce mis-sorting.

The report advises disposal labels should:

• Assume consumers will only give them 10 seconds or less
• Be placed on the front of pack
• Use recipient design (what the consumer needs to do, not what the producer knows)
• State clearly how and where to dispose of the item

WRAP also reinforced the need for clarity. Dr Thomas Baker, WRAP Specialist (Plastics), said clear, accurate, simple disposal instructions are essential to prevent confusion and mis-disposal.

Beyond labels: build trust and understanding with ‘restorative narratives’

The report argues that labels alone can’t carry the full burden of education. It recommends extended engagement via websites, social media, advertising and other channels—and calls for “restorative narratives” that present consumers as active contributors to a circular economy. This approach can help avoid “collapse of compassion”, where constant negative environmental messaging leads to disengagement.

Shellworks’ Senior Sustainability Strategist Katherine Manshreck noted that biomaterials can now look and perform like conventional packaging, making language on-pack even more important: consumers may not recognise a compostable material without clear wording, particularly as greenwashing has made visual cues like leaf icons less meaningful.

The findings build on BB-REG-NET’s earlier work highlighting a major economic opportunity for the UK bioeconomy, while warning that fragmented policy and unclear communication remain barriers to adoption. As Gavins pointed out, recycling behaviour was once unfamiliar too—suggesting that with consistent systems and better communication, the same transition is possible for bio-based and compostable materials.