Over the past decades, Ireland has become a global leader in the production of various medical devices. Its innovative approach to biomedical manufacturing and supportive academic and economic ecosystem has paid off, and the country is now considered a hub for the medtech industry.

Due to this incredible success, concerns about potential consequences are emerging. The biggest ones are the environmental, as the main component of most devices is polymers.

Although bad reputationally, all plastic types cannot be treated as nature’s worst enemy. Many factors contribute to the level of their harmfulness, some of which are already known, but others are yet to be discovered.

Despite the common belief, microplastics as particles are not the main concern related to environmental pollution, but the uncertainty related to the toxicity of products of their reactions and molecules leached from their composition. The best approach is to look holistically – at the whole lifecycle of the plastic product and the waste associated with it.

Apart from the Irish context in terms of environmental concerns of medical polymers, the article provides an overview of recycling methods and suggestions for the required changes in the whole value chain of medical devices. It includes design for sustainability, recycling innovations, and the support of the stakeholders.

As a manufacturer, I feel a social responsibility to ensure actions I take every day ideally align with both organisational and environmental goals. I believe they can be combined and measured under the same key performance indicators to ensure resource waste reduction, including energy, raw materials, time, capital, and any others of no value. 

Plastic waste and challenges of recycling 

Plastic provided both solutions to significant challenges and environmental concerns. According to Zhang et al (2021), the worldwide production of polymers increased by more than 350 million tonnes in a mere 70 years, causing a serious challenge to its recycling.

When plastic enters the environment, it undergoes different degradation processes (as shown in Figure 1), starting from mechanical breakage due to shearing forces, resulting in scratches or fragmentation with a higher surface-to-volume ratio (microplastics MPs and nano-plastics NPs).

Thus, chemical degradation progresses by UV, temperature, and amplified interaction with various particles (see Figure 2) and generate potentially toxic molecules. The debris could travel with water currents to distant locations(Cooper and Corcoran 2010). 

Figure 1: Different paths of plastic degradation in the environment (Zhang et al. 2021). 

Figure 2: Different types of interactions between microplastics and other particles (Luo et al. 2023). 

Smaller, aged particles, as highlighted by Luo et al. (2023), increase the risk of toxicity and surface’s contaminants. Different forms of degradation cause the cleavage of polymer chains or detrimental cross-linking, which increases their persistence in nature.

Zhang et al. (2021) emphasise that entry of significant plastic waste from various sources into the environment is unavoidable. The biotic degradation, which creates MPs, the overgrowth of microbiomes or greenhouse gases is another example of plastic deterioration.

Apart from the size, the danger related to microplastics roots also from leaching of toxic ingredients from their composition (plasticisers, stabilisers), and their unstable nature as the reactive species. Consequently, their potential to harm the environment is hard to predict as it depends on newly formed particles and leached additives (Biale et al. 2022).

Further research (especially outside of laboratory settings) is needed to fully understand the complexity of environmental concerns surrounding polymers. 

The challenge of plastic recycling and material lifecycle 

Cooper and Corcoran (2010) stress the requirement for degradation assessment before updating regulations. The number of resins recycled is an estimate of 5% and production of polymers has increased by 2,500% in 40 years. Therefore, the challenge remains, despite the efforts made by environmental authorities to establish regulations aimed at increasing recycling percentages.

Plastic waste consists of up to 80% of sea waste and is growing unproportionally fast compared to other materials. Evaluating the toxicity of materials guides usage reduction and selection of alternatives.

The complex composition of the polymers poses a significant challenge for the effective and standardized reutilisation methods. Two forms of plastics in terms of their recyclability are thermoplastics (can be melted) and thermosets (once cured, cannot be re-melted).

Figure 3 displays various methods of recycling (primary and secondary – mechanical, tertiary and quaternary – chemical) and by degradation. All methods have benefits and drawbacks – example of incineration outputs is presented in Figure 4.

The recent strategy is the conversion of the economy from linear to circular (based on the product Life Cycle Assessment (LCA)), which aligns with sustainable international objectives (Vlasopoulos et al. 2023). 

Figure 3: Methods of plastic disposal by recycling and degradation (Vlasopoulos et al. 2023). 

Figure 4: Outputs of the incineration plant (Vlasopoulos et al. 2023).  

Waste includes more than just polymers. Johnson et al. (2007) highlight the negative impact of stainless-steel production such as carbon dioxide releasement and high energy demand. Therefore, products with diverse materials (for example medical device – see Figure 5) pose recycling challenge due to components separation difficulties.

Huaiwei and Xin (2011) notes steel manufacturing hazardous waste creation and the need in shifting an approach to recover scarce metals. The challenge in recycling modern components of medical devices such as conventional electronics (eg, sensors) lies in their complexity, which hinders the easier path of device reusability. Technological advances created the first biodegradable and biocompatible electronics to address both issues (Hosseini et al. 2021). 

Figure 5: An example of a medical catheter with bonded layers of polymer and braided metal (Yildirim et al. 2019). 

Growth of the medical device sector 

Factors such as demographic changes and innovations increase the demand of medical devices. McKernan and McDermott (2022) describe Ireland as a leader in the medtech industry, with more than 450 companies, including global corporations.

Ireland is in the top five medical clusters in the world with the highest number of patents per person (see Figure 6) and is the second main exporter of devices in Europe. If the trends continue, Ireland will significantly intensify its production, which means amplified manufacturing waste and higher energy demand. Hence, this calls for increased focus on environmental concerns.  

Figure 6: Comparison of number of MedTech patents in Europe and Ireland (McKernan and McDermott 2022). 

What happens to used medical devices? The problem of a biohazard 

There are two routes by which products become waste: either through non-conformance during production or upon reaching the end of their life cycle (Zhang et al 2021).

The polymers are fundamental for medical technology due to their low cost, versatility, mouldability, and ability to enhance the properties for specific applications and surface modification.

Most of devices are single use as contact with a patient’s body fluids poses a biohazard risk. Therefore, usually used apparatus (about 1.7 million tonnes/year in the US alone) is incinerated. However, this high-energy disposal method contributes to air pollution, and toxic residues.

Recycling medical devices is complex due to diverse material layers, varied lifecycle stages during disposal. Plastic’s degradation resistance, which ensure long shelf life and biocompatibility, is simultaneously its environmental disadvantage (Joseph et al. 2021).

Kheirabadi and Sheikh (2022) emphasise the importance of adopting an innovative recycling management for medical waste that includes reprocessing and disinfection for reusability. A rigorous verification would be required to ensure risk and functionality assessment.

How to help patients without harming the environment around them? Addressing environmental impact in medical device production

Implementation of the sustainability mindset in healthcare industry introduces difficulty as ecological considerations may be deemed a lower priority compared to patient health. The multimaterial construction of contemporary medical devices significantly increases the challenge of separation for recycling purposes.

A complete shift is required to ensure the sustainability of the materials and processes. Therefore, design for sustainability and involvement of all the stakeholders from the medtech sector.

Benedettini (2022) states that three main global medical manufacturers USA, Europe, and Japan have a different approach to waste management, but the common goal is to rethink single-used devices and introduce reprocessing, reusability, and circular supply chain after analysis of device’s safety and efficacy.

Miller’s research (Miller 2013) provides early concept of water-degradable polymers as an alternative to contemporary ones (see Figure 7), which will require further research for integration with highly regulated medtech industry. 

Figure 7: Adding acetal functional group to polymer created water-degradability (Miller 2013). 

In parallel, vendors’ continuous efforts on replacement of potentially toxic polymer additives with ecofriendly alternatives must be supported by customers (Joseph et al. 2021).

Nevertheless, the arrival of novel approaches does not imply a lack of current innovation opportunities for manufacturers. Incremental innovative ideas can be as effective as radical innovation in reduction of defective products and waste, which having no value, disrupt process flow, frustrate employees and lead to financial losses. Therefore, Lean Six Sigma minimise variations, improve efficiency, and streamline processes.

As a manufacturing engineer, I initially focused on voice of the customers (VOC) and the voice of the process (VOP) to perform improvement gap analysis. The evaluation revealed the need for many gradual updates, instead of a major change to reduce creeping inefficiencies and defects.

The brainstorming session with assembly line operators helped to surface most apparent issues, such as for example settings adjustment of the laminating machine to create different programs for shorter sizes to save energy and cycle time.

It was beneficial to address simpler tasks prior to encountering more complex challenges. Especially since the global events caused disruptions to the supply chain, urging procurements and validation of the critical components from alternative vendors.

Additionally, resin formulation changes happened in consequence of international instabilities and medical regulations updates. Thus, revalidation and biocompatibility testing samples were required to ensure supply continuity. Subsequently, challenging the status quo for current manufacturing processes, including quality and documentation considerations was required.

The product’s specification is usually stable at the high-volume production stage. However, internal specification ensures the final device will meet the customer’s requirements.

While assembling the device, overall length issue was discovered, originating from too broad specification range, so internal documentation had to be narrowed down to obtain the reduction of the process variation.

Another modification with a collaboration with quality engineer was to address customer complaints (VOC) about kinks in a device, enhance efficiency and reduce packaging material. Investigation exposed the kink’s occurrence during the final operation. Packaging method redesigning reduced the materials usage, released the resources, and acted as a preventative measure against kinks. 

In parallel, some initiatives were introduced within the organisation, such as the energy conservation team, collection of rejected metal components to restore energy and rare elements by incineration and incorporation of virtual reality (VR) to reduce the risk of device damage during training.

Aligning business needs with ecological goals bring benefits of resources allocation for further investment opportunities. Inefficiency is contrary to the environmental objectives.

Transitioning from technician to engineer, my projects assigned by management (based on key performance indications KPI) focused on reducing defects. Through successes and challenges, Lean Six Sigma facilitated process optimisation. Considering LCA, even one device that won’t reach medical applications has far more negative impact for patients, business, employees, and the environment. 

A look into a future: Solutions for plastic waste at highly regulated environment of medical device production 

A holistic approach to material management at highly regulated organisations is crucial for the whole value chain that requires support from all parties. Given the challenges in recycling medical devices, exploring harmless biodegradable polymers and closed-loop approach is necessary to reduce usage of virgin raw materials and related transportation (Joseph et al 2021).

Implementing design for sustainability (see Figure 8) based on product LCA and reusability is needed. Kheirabadi and Sheikhi (2022) notice the need to focus on quaternary recycling options aimed at generating diverse products from recovered medical materials. However, industry standards will have to follow that strategy.

Alternative approach to manufacturing waste is transition to additive manufacturing, such as 3D printing incorporating environmentally friendly polymers. This technology minimises the material usage and offers versatile customisation.

Continuous education of workforce is crucial. I am impressed by the national emphasis on sustainability incorporated into the traditional courses, such as master of science in mechanical engineering with an option to study zero-carbon technology (Trinity College Dublin 2023). 

Figure 8: Proposal of practices for polymer medical device design for sustainability (Joseph et al. 2021). 

Conclusions

The complexity of the interaction between particles and aged polymers poses many environmental concerns. Therefore, various actions are required to reduce the material usage, such as sustainably design of products and processes and circular economy.

Adopting a sustainability mindset in medical device manufacturing imposes innovation and involvement of the entire value chain to achieve systematic reduction of negative environmental impact. This holds particular significance within the Irish market because of medtech expansion.

Strategic and tactical business decisions should focus on dedicating resources to this social responsibility. Frequently, overcoming limitations creates innovation opportunities for organisational culture shift. 

Author: Ewa Ziemichod is a professional with 16 years of experience at Freudenberg Medical, currently serving as a manufacturing engineer at VistaMed in Carrick on Shannon, where her role is to incorporate lean and six sigma philosophies to enhance the efficiency of manufacturing processes for medical devices, contributing to the advancement of quality and innovation. She is in the final year of pursuing a bachelor's degree in science and technology from the University of Galway.

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