The world of biomanufacturing is full of technical terms that can be opaque to consumers.
One of these is bio-attribution – a term that is everywhere yet rarely explained.
What exactly does it mean? How does it differ from a bio-based product? And is it sustainable?
The confusion
Bio-attribution is a term used everywhere in the bioeconomy.
According to its proponents, it is a tool that can decarbonise the chemical industry.
For instance, the ongoing partnership between AkzoNobel, Arkema and BASF has been sourcing bio-attributed raw materials. According to them, bio-attribution has helped lower the carbon content of AzkoNobel’s architectural coatings.
Often, bio-attributed products hint at some relationship between the item and renewable feedstocks – whether plants, fungi, algae, or agro-waste – but the exact nature of the relationship is often unclear.
Although often pitched as the lower-carbon choice, the label is rarely explained, leaving buyers in the dark about what it is they are actually purchasing and whether it indicates a more sustainable choice.
What does bio-attribution mean?
Bio-attribution is a product label that communicates to the consumer that the company that made it is buying and using renewable feedstock.
More formally, it verifies that the product came out of a manufacturing system (a factory, or a supply chain) that used a certain amount of bio-based raw materials.
The bio-attribution label also tells the consumer that the amount of bio-based material that leaves that manufacturing system, in the form of products, matches the amount of biomass raw materials originally fed into that system – i.e. that bio-based feedstock is actually reaching the economy and not being wasted in the production process, for example.
We are using the very abstract term of ‘manufacturing system’ here for deliberate reasons.
This is because a bio-attribution could, in theory, operate at very different scales.
Bio-attribution could apply to the entire economy of a single country or the global bioeconomy. As a product label, however, it is making much narrower claims – about the presence of renewable materials in a company’s production line.
What does bio-attribution not mean?
There are certain things that bio-attribution labels do not tell you.
When you see a bio-attribution label on a product, it does not tell you anything about the exact amount of renewable material content inside that particular item.
In other words, any individual bio-attributed product that you buy is not necessarily composed of any bio-based molecules at all, although it could be.
This is because the point of bio-attribution accounting is not verifying the bio-based content inside any particular bioplastic bag, a tin of bio-based paint, or a bio-based textile material.
Rather, it aims to indicate the renewable content fed into the manufacturing system that produced them.
While a bio-attribution label on a product does not guarantee that there are any bio-based molecules in that particular item, it does guarantee that a certain amount of biomass was bought by the manufacturer and used by them.
This means that the original biomass feedstock that went into the plant is out there in the economy somewhere, or will eventually be, in other tins of paint, bioplastic bags, or bio-based textiles.
The question of which exact products a particular batch of biomass raw materials ends up in is not a concern under the bio-attribution scheme.
This is because it aims to track the overall amount of renewable, low carbon feedstock being used in an entire system – usually a single manufacturing plant or a single manufacturing company.
Why do companies use bio-attribution?
Bio-attribution is solving particular problems for the chemicals industry. Primarily, it is solving the problem of proving to consumers that the company is buying renewable feedstocks.
Why do companies need this? The reason is that most chemical companies often use both bio-based and fossil raw materials in their manufacturing plants to make a vast range of chemical products.
Often, the bio-based and fossil-based chemicals are indistinguishable to the naked eye.
Companies choose to draw on both renewable and non-renewable chemicals for several reasons.
Blending renewable and petrochemicals in a manufacturing operation can strike a balance between product performance and sustainability targets. It may be that 100% bio-based materials cannot yet match petrochemicals on performance in certain applications.
The higher cost or low availability of some renewable chemicals is another reason companies do not go fully bio.
Biobased supply chains are still maturing and biobaesd feedstock often cannot compete on price with petrochemicals.
In this situation, drawing on both fossil and bio-based feedstocks is a route to keeping production costs down. Incorporating cheaper petrochemicals lowers the cost while renewable feedstocks can reduce the carbon footprint of the final product compared to a purely fossil-based item.
Bio-attribution allows companies to communicate to consumers that, for whatever reason, their products are not all 100% bio-based but that they are participating in the bioeconomy as buyers and users of renewable feedstock.
Bio-attribution gives a systematic method for companies to assure the consumer that they are using renewable feedstock – if not in the actual product they are holding, then in their manufacturing system at large.
How do products get bio-attributed?
Working out just how much renewable raw materials relative to petrochemicals are flowing through a plant at any given time is a technically demanding task.
In a chemical refinery, it is hard to keep track of how different feedstocks blend and interact as manufacturing processes get underway.
This is why placing a bio-attribution label on a product depends on rigorous assessments and calculations. The framework for doing this is the mass balance model.
The mass balance model is a method that allows a company to account for all raw material inputs into a system.
It offers a systematic method to trace raw materials flows, ensuring the raw material inputs into a system match the outputs via predefined calculations. It accounts for raw materials that get lost or are gained in the manufacturing process too.
The final goal of mass balance is to work out what ratio of renewable materials to fossil raw materials a company can attribute to end products.
There are two recommended mass balance methods outlined by the International Standards Organisation (ISO).
Under one of these methods, one factory buys a yearly average ratio of virgin fossil to renewable feedstock (9:1). This average ratio of renewable to fossil feedstock is attributed to all outputs that come out of the plant that year.
This drives home the purpose of mass balance accounting and the bio-attribution label that it supports. The aim is not to find the precise bio-based content of this or that product – with bio-attribution, we are instead talking about inputs, systems, and averages.
Who awards bio-attribution?
Companies themselves usually carry out the mass balance calculations and award their own products the bio-attribution labels.
However, for bio-attribution labels to be meaningful, their mass balance studies must be confirmed by independent auditors.
ISCC PLUS and REDcert schemes are two common certification processes used in the chemical sector to ensure that the mass balance model is being used correctly. Independent auditors under these schemes conduct site visits to check whether product bio-attributions are accurate.
Independent auditors often look to the ISO 22095:2020 for their checks. The code gives an international set of criteria for how to conduct mass balance calculation.
This includes documentation about the origin, quantity, and character of the input raw materials in a system, and the use of a third party auditors to verify their systems.
Hype or not?
Bio-attribution is an important consumer labelling tool that can help scale a bio-based supply chain. It does this by promoting the products of businesses that use renewables feedstock.
Since the label is a reliable signal that a producer is bulk buying renewable feedstock, it allows consumers to reward companies shifting to lower-carbon manufacturing inputs.
The mass balance method that bio-attribution labels rely on is also important to keep track of renewable resource claims.
With different feedstocks interacting at every stage of the supply chain, a method for working out the balance of renewable and fossil materials involved in a productive process can be useful at a corporate level for sustainability accounting.
Other tools still relevant
Incentivising companies to use more renewable feedstock is a critical part of scaling renewable supply chains. Bio-attribution labels are one way to achieve this.
However, consumers should also be aware that sustainability is a multi-faceted thing. Bio-attribution does not mean that the product is necessarily lighter on the environment than fossil-based ones.
For example, a bio-attributed product is not necessarily biodegradable – something that poses a risk to biodiversity, human health, and wildlife.
This points towards how assessing sustainability requires multiple tools.
Alongside bio-attribution, consumers must also reach for other assessment frameworks, such as international standards that test for product biodegradability, or life cycle assessments (LCA).
LCAs are the only way to put a precise number on the carbon emissions and other environmental impacts associated with making a product. It remains one of the most reliable and nuanced indicators of sustainability out there.
Decarbonising industry will depend on multiple methodologies to measure and communicate environmental performance. Bio-attribution is just one of them.
