Beyond “less harmful”: new BioSusTex research asks when a product is sustainable enough
A new BioSusTex-supported paper explores the historical incorporation of environmental limits in Life Cycle Assessment (LCA), exploring how sustainability assessment in Safe and Sustainable by Design (SSbD) can move beyond comparing which product is greener and begin asking a harder question: does a product operate within the environmental limits of our planet?
When companies describe a product as “more sustainable”, the comparison is usually relative. A new material may use less energy than the one it replaces. A manufacturing process may emit less CO2. A new garment may require less water than a conventional alternative. These improvements matter. But they leave an important question unanswered: is the environmental impact actually low enough?
A newly published paper supported by BioSusTex trace the history of how sustainability assessment started to develop methods to answer that question. Planetary Boundaries and Absolute Sustainability in Life Cycle Assessment – past, present, and future was developed by researchers from Ca’ Foscari University of Venice, GreenDecision, IVL Swedish Environmental Research Institute, the Technical University of Denmark and Emerge Ltd. The study examines how environmental limits have been incorporated into Life Cycle Assessment over several decades and how the increasingly influential Planetary Boundaries framework is being developed to support companies assess whether products, materials and technologies are not simply better than existing alternatives, but compatible with the Earth’s capacity to support human activity.
The difference between “better” and “good enough”
Life Cycle Assessment, usually known as LCA, is one of the most widely used tools for understanding the environmental footprint of a product. Rather than looking only at what happens in a factory, an LCA can consider impacts across the product’s life cycle: raw materials, manufacturing, transport, use and eventual disposal or recycling. Traditionally, LCA has been particularly useful for comparisons. Is material A better than material B? Does one manufacturing route create less climate impact than another? Which design causes fewer environmental pressures? The new paper describes this as a relative approach: one option is judged against another. Other environmental assessments already work differently. Chemical risk assessment, for example, commonly compares exposure against a defined safety threshold. The question is not only whether one chemical is safer than another, but whether exposure remains below a level considered safe. The researchers argue that sustainability assessment increasingly needs both perspectives. A product can be 20% better than its predecessor and still place too much pressure on the environment. In that situation, improvement has occurred but the product may still not be sustainable in an absolute sense.
What are Planetary Boundaries?
The Planetary Boundaries framework attempts to identify environmental limits within which humanity can operate while maintaining a relatively stable Earth system. It considers major Earth-system processes such as climate change, freshwater change, land-system change, biosphere integrity, ocean acidification and the introduction of novel human-made substances and materials. Rather than asking only whether environmental performance has improved, these boundaries introduce the idea of a Safe Operating Space: environmental pressures must remain within limits that protect the functioning of the wider Earth system. Researchers have therefore begun combining Planetary Boundaries with LCA in what is known as Absolute Environmental Sustainability Assessment.
The principle sounds straightforward: calculate a product’s environmental impact and compare it with the amount of environmental pressure that can safely be accommodated. In practice, however, this raises a difficult question.
How much of the planet’s “environmental budget” belongs to one product?
A planetary boundary is global. A T-shirt, mobile phone, building material or chemical is not. To assess an individual product, researchers therefore need to translate global environmental limits into smaller shares. Imagine that the planet has a limited environmental “budget” for a particular pressure. How much of that budget should be allocated to clothing? How much to housing, food, healthcare or transport? Within clothing, how much should belong to one garment? And should that allocation depend on population, economic value, human needs, historical responsibility or some other principle? There is no purely scientific answer.
The paper identifies this as one of the central challenges facing absolute sustainability assessment. Different principles for sharing the Safe Operating Space can produce substantially different thresholds for the same product. This means that the assumptions behind the result need to be visible.
Sustainability involves values as well as science
One of the paper’s central ideas is what the authors call the “valuesphere.” Environmental limits may be grounded in scientific evidence, but turning a global limit into a practical threshold inevitably involves choices: who receives what share, which activities society considers necessary, what time horizon is used and how responsibility is distributed. These decisions involve ideas about fairness, social priorities and acceptable risk. The authors argue that sustainability assessments should therefore make these choices explicit instead of presenting the final threshold as if it were entirely value-free. Doing so could make absolute sustainability assessments more transparent, easier to interpret and ultimately more credible. For the public, this has an important implication: sustainability cannot always be reduced to a single objective score. Science can tell us a great deal about environmental pressures and ecological limits. Deciding how those limits should be shared across societies, industries and products also requires societal choices.
Why this matters for the products of the future
The issue becomes particularly important when developing new materials and technologies. Suppose a company develops a new textile fibre with a lower climate impact than conventional polyester. A traditional LCA can tell the company whether the new fibre performs better. But if that new fibre were manufactured on a massive global scale, would its overall environmental pressure still remain within a sustainable share of planetary limits? That is a different question.
The paper argues that emerging technologies should ultimately be assessed against both criteria: are they better than what exists today, and are they good enough for a sustainable future? This distinction is especially relevant to the European SSbDapproach, which aims to consider safety and sustainability while chemicals and materials are still being designed, rather than addressing environmental problems only after they reach the market.
The authors propose combining conventional comparative LCA with absolute sustainability assessment. Comparative LCA would identify whether a new solution improves on current practice, while assessment against Planetary Boundaries would examine whether that improvement is sufficient in the context of wider environmental limits. Their message can be summarised simply:
Future solutions should be both “better” and “good enough.”
What does this mean for BioSusTex?
For BioSusTex, this research addresses a fundamental challenge behind the development of safer and more sustainable textiles. Replacing one fibre, chemical or manufacturing process with a lower-impact alternative is an important step. But the long-term goal is larger: textile systems need to function within environmental limits even when technologies are deployed at commercial scale. That means asking questions such as:
** Can a new material remain sustainable if millions of tonnes are produced?
** Does reducing climate impact create greater pressure elsewhere, such as on land, water or biodiversity?
** How should the environmental space available to textile production be determined?
** And how can these considerations be incorporated early enough to influence material and product design?
The study does not claim that these questions have simple answers. Instead, it maps how sustainability assessment has evolved and identifies what is still needed to turn Planetary Boundaries into useful decision-making tools for products and industries.
From eco-efficiency to absolute sustainability
The paper also places today's debate in historical perspective. Environmental assessment has been incorporating different kinds of limits for decades. Earlier approaches often relied on national policy targets, regulatory limits or region-specific environmental goals. The Planetary Boundaries framework shifts the focus towards global Earth-system limits. The authors argue that this represents more than a methodological change. It reflects a broader change in how sustainability itself is understood.
Making a process more efficient does not necessarily mean that the resulting level of production and consumption can be sustained indefinitely. The researchers therefore distinguish between reducing impacts within today's system and designing systems capable of operating within environmental limits over the long term.
This also means that technology alone may not provide every solution. Production volumes, consumption patterns, business models and the way environmental responsibility is shared may all need to become part of the discussion.
Building better sustainability decisions
Absolute sustainability assessment is still developing. The researchers highlight several unresolved challenges, including translating global boundaries to local and product scales, dealing with uncertainty, choosing fair allocation principles and incorporating future production and consumption scenarios. Rather than replacing existing LCA methods, the paper proposes strengthening them.
Comparisons remain valuable because companies need to know whether one technology is better than another. Planetary Boundaries add another layer: whether those improvements are sufficient to contribute to a world operating within environmental limits.
The authors conclude that combining these perspectives could strengthen Safe and Sustainable by Design and help companies make more meaningful decisions about emerging chemicals, materials and technologies.
For consumers, the underlying idea is straightforward. In the future, calling a product “sustainable” may need to mean more than saying that it performs better than yesterday’s alternative. It may also need to demonstrate that its environmental footprint is compatible with the conditions required for people and ecosystems to thrive.
The work was supported by several European research initiatives, including BioSusTex (Grant Agreement 101135372), together with CheMatSustain and SunRise.
Read the open-access paper: