LCA in medical electronics: Key levers for sustainability

An EEG sensor is slowly taking shape in the lab. A newly developed electronic structure is replacing the traditional printed circuit board, integrating mechanical and electronic functions more closely. The initial results are promising: Compared to the conventional PCB-based EEG sensor, the prototype has a 40 percent lower environmental impact. However, the analysis also reveals areas for further improvement. This is because the chemical baths used in the new manufacturing process contribute significantly to the remaining environmental impacts.

These findings come from the European research project SUSTRONICS. Between 2023 and 2026, 46 partners from eleven European countries worked on more sustainable and circular electronics. The applications studied included EEG sensors and smart wound dressings.

Life cycle assessments (LCA) were conducted across several generations of development for these products. The project partners used an existing solution or the first product generation as a reference, identified components and processes with particularly significant environmental impacts, and incorporated the results into further development decisions.

Materials, electronic components, and manufacturing processes contribute to the environmental impact of a medical device to varying degrees. It is therefore crucial for developers to determine which factors carry the most weight for a specific product.

In the SUSTRONICS project, life cycle assessment was used to identify these key environmental issues early on. Based on an initial assessment, the project partners formulated development goals, tested alternative technologies and materials, and re-evaluated their environmental impact. This creates a feedback loop between environmental assessment and product development. Developers receive a data foundation that shows where changes can have the greatest impact.

Two medical examples from the project illustrate just how varied such development decisions can be.

For EEG monitoring, SUSTRONICS investigated an alternative to the conventional PCB-based sensor. The company used a so-called LDS-MID structure, in which conductive traces are formed directly on three-dimensional plastic components. This allows electronic and mechanical functions to be more closely integrated.

At the same time, the life cycle analysis identified the next area for improvement: The chemical baths used in the LDS process contribute significantly to the remaining environmental impacts. For industrial implementation, optimizing manufacturing yield and scaling up production also play an important role.

SUSTRONICS began working on the smart wound dressing early in the development phase. Among other things, the system measures temperature and pH. Since the application was still in an early stage of development, sensor requirements could be considered alongside decisions regarding materials, manufacturing processes, and product architecture.

Comparison of materials and manufacturing processes

For flexible electronics, the project examined two manufacturing approaches:

• Subtractive manufacturing: Copper conductive traces on a stretchable, partially bio-based TPU substrate.
• Additive printed electronics: Substrates such as paper and PLA (polylactide), as well as carbon for the conductive structures.

Additive printed electronics requires less energy and material, involves fewer process steps at lower temperatures, and allows for a wider selection of substrate materials. Carbon on paper also enables a fully biodegradable layered structure.

Targeted separation of single-use and reusable components

The product architecture also offers a starting point. The concept separates the flexible, single-use electronics of the wound dressing from a reusable readout unit. As many electronic components as possible should be housed in the reusable unit, since encapsulated integrated circuits contribute significantly to the carbon footprint of small electronic systems.

The recorded wound parameters can also support longer intervals between dressing changes and earlier detection of infections. This offers the potential to save materials and reduce the number of visits by healthcare professionals through remote monitoring.

The project experience led to the development of the so-called Eco2Design process, which combines environmental assessment with product development. The starting point is a baseline analysis that identifies key environmental issues and lays the foundation for specific sustainability goals. During further development, potential solutions are implemented and re-evaluated. Data from pilot applications can then refine the assessment and support further optimizations.