Combining Life Cycle Assessment and Circularity Assessment to Analyze Environmental Impacts of the Medical Remanufacturing of Electrophysiology Catheters

Sustaining value after the end-of-life to improve products’ circularity and sustainability has attracted an increasing number of industrial actors, policymakers, and researchers. Medical products are considered to have great remanufacturing potential because they are often designated as single-use products and consist of various complex materials that cannot be reused and are not significant in municipal recycling infrastructure. The remanufacturing of electrophysiology catheters is a well-established process guaranteeing equivalent quality compared to virgin-produced catheters. In order to measure if using a remanufactured product is environmentally beneficial compared to using a virgin product, life cycle assessment (LCA) is often used. However, focusing on one life cycle to inform on the environmental-beneficial use fails to guide policymakers from a system perspective. This study analyzes the environmental consequences of electrophysiology catheters considering two modeling perspectives, the implementation of LCA, including a cut-off approach and combining LCA and a circularity indicator measuring multiple life cycles. Investigating the LCA results of using a remanufactured as an alternative to a newly-manufactured catheter shows that the global warming impact is reduced by 50.4% and the abiotic resource use by 28.8%. The findings from the system perspective suggest that the environmental savings increase with increasing collection rates of catheters.

Abiotic resource depletion potentials (ADPs) for elements revisited—updating ultimate reserve estimates and introducing time series for production data

Purpose In 1995, the original method for assessing the impact category abiotic resource depletion using abiotic depletion potentials (ADPs) was published. The ADP of a resource was defined as the ratio of the annual production and the square of the ultimate (crustal content based) reserve for the resource divided by the same ratio for a reference resource (antimony (Sb)). In 2002, ADPs were updated based on the most recent USGS annual production data. In addition, the impact category was sub-divided into two categories, using two sets of ADPs: the ADP for fossil fuels and the ADP for elements; in this article, we focus on the ADP for elements. Since then, ADP values have not been updated anymore despite the availability of updates of annual production data and also updates of crustal content data that constitute the basis of the ultimate reserves. Moreover, it was known that the coverage of elements by ADPs was incomplete. These three aspects together can affect relative ranking of abiotic resources based on the ADP. Furthermore, dealing with annually changing production data might have to be revisited by proposing new calculation procedures. Finally, category totals to calculate normalized indicator results have to be updated as well, because incomplete coverage of elements can lead to biased results. Methods We used updated reserve estimates and time series of production data from authoritative sources to calculate ADPs for different years. We also explored the use of several variations: moving averages and cumulative production data. We analyzed the patterns in ADP over time and the contribution by different elements in the category total. Furthermore, two case studies are carried out applying two different normalization reference areas (the EU 27 as normalization reference area and the world) for 2010. Results and discussion We present the results of the data updates and improved coverage. On top of this, new calculation procedures are proposed for ADPs, dealing with the annually changing production data. The case studies show that the improvements of data and calculation procedures will change the normalized indicator results of many case studies considerably, making ADP less sensitive for fluctuating production data in the future. Conclusions The update of ultimate reserve and production data and the revision of calculation procedures of ADPs and category totals have resulted in an improved, up-to-date, and more complete set of ADPs and a category total that better reflects the total resource depletion magnitude than before. An ADP based on the cumulative production overall years is most in line with the intent of the original ADP method. We further recommend to only use category totals based on production data for the same year as is used for the other (emission-based) impact categories.

Toward Science-Based and Knowledge-Based Targets for Global Sustainable Resource Use

The article discusses key aspects to be considered for the orientation of sustainable resource policies. Resource management at the local scale needs to be supplemented by governmental action in order to adjust production and consumption toward acceptable levels of global resource use. What is acceptable is being informed by scientific findings on environmental degradation and relevant cause–effect relationships. However, the desired state of the environment, the tolerable level of uncertainties about environmental impacts, risks of societal conflicts, and ethical considerations all involve normative considerations. Policy decisions for sustainable global resource use must be taken on the basis of imperfect information. A wider systems perspective, longer time horizon, and broader involvement of available knowledge could provide a sufficiently valid basis to derive directionally safe targets. Possible proxy targets for global biotic and abiotic resource use, considering land, biodiversity, and water issues, are presented on a per-person basis for 2050 for further discussion and research. These values could be used to assess the resource footprints of countries with regard to sustainability, providing orientation for governments and industry.

Diversification of light capture ability was accompanied by the evolution of phycobiliproteins in cryptophyte algae

Evolutionary biologists have long sought to identify phenotypic traits whose evolution enhances an organism's performance in its environment. Diversification of traits related to resource acquisition can occur owing to spatial or temporal resource heterogeneity. We examined the ability to capture light in the Cryptophyta, a phylum of single-celled eukaryotic algae with diverse photosynthetic pigments, to better understand how acquisition of an abiotic resource may be associated with diversification. Cryptophytes originated through secondary endosymbiosis between an unknown eukaryotic host and a red algal symbiont. This merger resulted in distinctive pigment–protein complexes, the cryptophyte phycobiliproteins, which are the products of genes from both ancestors. These novel complexes may have facilitated diversification across environments where the spectrum of light available for photosynthesis varies widely. We measured light capture and pigments under controlled conditions in a phenotypically and phylogenetically diverse collection of cryptophytes. Using phylogenetic comparative methods, we found that phycobiliprotein characteristics were evolutionarily associated with diversification of light capture in cryptophytes, while non-phycobiliprotein pigments were not. Furthermore, phycobiliproteins were evolutionarily labile with repeated transitions and reversals. Thus, the endosymbiotic origin of cryptophyte phycobiliproteins provided an evolutionary spark that drove diversification of light capture, the resource that is the foundation of photosynthesis.