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Background
The growing interest in sustainable construction practices has prompted research into alternatives to conventional synthetic binders used in engineered wood products. This paper investigates the environmental impact of replacing melamine-urea-formaldehyde (MUF)—a widely used synthetic resin in medium-density construction boards—with mycelium, a bio-based binding agent derived from fungal biomass.
This topic is important due to the high environmental footprint associated with MUF production and use, including formaldehyde emissions, reliance on non-renewable resources, and challenges in end-of-life disposal. In contrast, mycelium offers a renewable, biodegradable alternative that may reduce the carbon footprint and support circular material strategies in the building sector (Alaux et al. 2024; Candido et al. 2024; Maierhofer et al. 2024).
While existing studies have examined the use of mycelium in low-density applications such as insulation panels, little is known about its suitability and environmental performance when used in structural or medium-density boards. There is currently a knowledge gap concerning the life cycle environmental performance of mycelium versus MUF in this context.
This paper addresses that gap by conducting a comparative life cycle assessment (LCA) of MUF and mycelium binders intended for application in medium-density wood-based construction boards. The goal is to inform material choices in sustainable building design and contribute to the development of fully bio-based construction materials.
Keywords: LCA, Mycelium, MUF, Medium density fibreboards.
Experimental
This study employs a comparative Life Cycle Assessment to evaluate the environmental performance and carbon footprint of alternative binders used in particle board manufacturing. The assessment follows the methodology specified in EN 15804+A2, ensuring compliance with current European standards for construction products.
Two types of binders were analyzed:
• Bio-based mycelium, representing an innovative, renewable alternative.
• Melamine-urea-formaldehyde, a conventional fossil-based resin used widely in the wood industry.
Due to the early-stage development of the MyCobuild project, inventory data for mycelium were obtained from peer-reviewed literature. In contrast, the life cycle inventory for MUF was based on data compiled during the 2024 development of an Environmental Product Declaration (EPD) for particle boards. A follow-up study incorporating primary data from laboratory-scale and pilot-scale production of mycelium is in an initial phase and primary data are expected to be collected within next six months.
The functional unit is defined as 1 kg of dry binder material. The system boundary covers a cradle-to-gate scope, including raw material acquisition, binder synthesis, and associated emissions—particularly CO₂ emissions during the biological growth phase of mycelium.
LCA modeling adheres to the principles of EN 15804+A2, with additional references to standard emission quantification protocols (e.g., EN ISO 14067 for carbon footprint of products, where applicable). These ensure methodological consistency and allow for robust environmental comparisons between the two binder systems.
This comparative framework supports a scientifically grounded evaluation of emerging bio-based binders and contributes to ongoing efforts to decarbonize engineered wood products in line with circular economy goals.
Results and Discussion
The comparative LCA conducted in this study reveals a substantially lower carbon footprint for mycelium-based binders compared to conventional MUF formulations. Within the cradle-to-gate system boundary, the results for mycelium show net negative carbon emissions. This outcome is attributed to the biological process by which mycelium absorbs carbon from organic substrates during its growth phase.
Although fungi lack the ability to photosynthesize, they play a significant role in carbon sequestration by metabolizing and storing carbon derived from decomposed organic matter. CO₂ emissions resulting from mycelial metabolic activity were accounted for in the analysis and represent approximately 20% of the total emissions associated with mycelium production (Livne et al. 2022; Nussbaumer et al. 2024). Despite these emissions, the overall incubation process is characterized by low energy demand, further contributing to the favorable environmental profile of mycelium.
In comparison, MUF production is associated with significantly higher fossil-based carbon emissions. Specifically, the climate change impact category related to fossil sources is more than six times greater for MUF than for mycelium (see Figure 1). These findings underscore the potential of mycelium as a low-impact, bio-based alternative binder in particle board manufacturing. The study does not include later stages of life cycle however scenarios considered in the literature indicate that mycelium’s performance at and of life is better than considered alternative (Alaux et al. 2024).
Figure 1. Figure presenting results.
Conclusions
This study demonstrates the promising potential of mycelium-based binders in reducing the carbon footprint of particle board production. The comparative LCA, conducted in accordance with EN 15804+A2, revealed that mycelium exhibits significantly lower fossil-based emissions than conventional MUF binders. Notably, the cradle-to-gate results for mycelium showed net negative carbon emissions, primarily due to its ability to sequester carbon from organic substrates during growth. Although metabolic processes in fungi contribute to some CO₂ emissions, these accounted for only a minor share of the total impact. The low energy demand of the incubation process further enhances the environmental performance of mycelium. Conversely, MUF production involves substantial fossil resource use and higher embodied energy. These findings highlight the environmental viability of mycelium as a binder in engineered wood products. The study also underscores the importance of expanding LCA research to include emerging bio-based materials in structural applications. Future work will incorporate laboratory-scale data to refine the inventory and validate the results under real production conditions. Overall, this research supports the transition toward more sustainable material choices in the wood industry.
References
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