Environmental sustainability assessment of biodegradable bio-based poly(3-hydroxybutyrate-co-3-hydroxyvalerate) from agro-residues: Production and end-of-life scenarios.

In the context of a circular bio-based economy, more public attention has been paid to the environmental sustainability of biodegradable bio-based plastics, particularly plastics produced using emerging biotechnologies, e.g. poly(3-hydroxybutyrate-co-3-hydroxyvalerate) or PHBV. However, this has not been thoroughly investigated in the literature. Therefore, this study aimed to address three aspects regarding the environmental impact of PHBV-based plastic: (i) the potential environmental benefits of scaling up pellet production from pilot to industrial scale and the environmental hotspots at each scale, (ii) the most favourable end-of-life (EOL) scenario for PHBV, and (iii) the environmental performance of PHBV compared to benchmark materials considering both the pellet production and EOL stages. Life cycle assessment (LCA) was implemented using Cumulative Exergy Extraction from the Natural Environment (CEENE) and Environmental Footprint (EF) methods. The results show that, firstly, when upscaling the PHBV pellet production from pilot to industrial scale, a significant environmental benefit can be achieved by reducing electricity and nutrient usage, together with the implementation of better practices such as recycling effluent for diluting feedstock. Moreover, from the circularity perspective, mechanical recycling might be the most favourable EOL scenario for short-life PHBV-based products, using the carbon neutrality approach, as the material remains recycled and hence environmental credits are achieved by substituting recyclates for virgin raw materials. Lastly, PHBV can be environmentally beneficial equal to or even to some extent greater than common bio- and fossil-based plastics produced with well-established technologies. Besides methodological choices, feedstock source and technology specifications (e.g. pure or mixed microbial cultures) were also identified as significant factors contributing to the variations in LCA of (bio)plastics; therefore, transparency in reporting these factors, along with consistency in implementing the methodologies, is crucial for conducting a meaningful comparative LCA.

Technical substitutability of recycled materials in life cycle Assessment: A comprehensive review and framework for quantification.

In evaluating environmental sustainability with methodologies like life cycle assessment (LCA), recycling is usually credited for avoiding impacts from virgin material production. Consequently, the LCA results are influenced by the manner in which the substitutability of virgin by recycled materials is estimated. This study reviews how the scientific community assesses the technical substitutability of recycled materials in LCA. Accordingly, 49 peer-reviewed papers were in-depth analysed, considering aspects such as materials studied, type of substitution, recycled material (rMaterial) application, and life cycle stages (LCSs) where substitution was evaluated. The results show that 49% of the papers investigated material substitutability through technical and economic aspects. 51% of the articles did not consider the final application of the rMaterial. Plastics were the most studied material, and mass was the most used property to quantify technical substitutability. Certain materials were more analysed in specific LCSs (e.g., metals in the natural resource extraction stage). As 51% of the papers developed a new approach for substitutability calculation, this shows that substitutability is still a concept in development. It was noticed in 33% of the papers that substitutability values were taken from external sources, and in some cases were used without considering whether they were representative for a specific case. Aspects such as harmonization, transparency, and consideration of the application of recycled materials, therefore, require more attention in substitutability evaluation. Based on the results, a step-wise framework to measure technical substitutability at different LCSs was developed to guide researchers in including substitutability in LCA studies.

Environmental performance of plastic food packaging: Life cycle assessment extended with costs on marine ecosystem services.

Packaging can play a substantial role in moving towards more sustainable food systems by affecting the amount of food loss and waste. However, the use of plastic packaging gives rise to environmental concerns, such as high energy and fossil resource use, and waste management issues such as marine litter. Alternative biobased biodegradable materials, such as poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) could address some of these issues. For a careful comparison in terms of environmental sustainability between fossil-based, non-biodegradable and alternative plastic food packaging, not only production but also food preservation and end-of-life (EoL) fate must be considered. Life cycle assessment (LCA) can be used to evaluate the environmental performance, but the environmental burden of plastics released into the natural environment is not yet embedded in classical LCA. Therefore, a new indicator is being developed that accounts for the effect of plastic litter on marine ecosystems, one of the main burdens of plastic's EoL fate: lifetime costs on marine ecosystem services. This indicator enables a quantitative assessment and thus addresses a major criticism of plastic packaging LCA. The comprehensive analysis is performed on the case of falafel packaged in PHBV and conventional polypropylene (PP) packaging. Considering the impact per kilogram of packaged falafel consumed, food ingredients make the largest contribution. The LCA results indicate a clear preference for the use of PP trays, both in terms of (1) impact of packaging production and dedicated EoL treatment and (2) packaging-related impacts. This is mainly due to the higher mass and volume of the alternative tray. Nevertheless, since PHBV has limited persistence in the environment compared to PP packaging, the lifetime costs for marine ES are about seven times lower, and this despite its higher mass. Although further refinements are needed, the additional indicator allows for a more balanced evaluation of plastic packaging.

Analysis of the Cultured Meat Production System in Function of Its Environmental Footprint: Current Status, Gaps and Recommendations.

Cultured meat has been presented as an environmentally friendlier option to conventional meat, but due to the limited data, the studies related to its performance are scarce and based on hypothetical production processes. This work provides a short literature review of the published environmental assessments of cultured meat. The main findings of this critical analysis showed that the lack of real data related to cultured meat decreased the level of accuracy of each study. The missing environmental profile of the process itself, including the proliferation and differentiation phases in bioreactors, along with key ingredients such as growth factors and other recombinant proteins, increase the difficulty of achieving reliable conclusions. In order to bridge the highlighted gaps, a complete production system is modelled and analysed from an engineering and life-cycle perspective. Furthermore, an overview of the supply chains of different products used in the process is provided, together with recommendations on how they should be considered in future life-cycle assessments. In essence, this work provides a structured pathway for upcoming consistent environmental assessments in this field, with the objective of setting the basis to understand the potential of cultured meat.

Environmental impact of non-certified versus certified (ASC) intensive Pangasius aquaculture in Vietnam, a comparison based on a statistically supported LCA.

Pangasius production in Vietnam is widely known as a success story in aquaculture, the fastest growing global food system because of its tremendous expansion by volume, value and the number of international markets to which Pangasius has been exported in recent years. While certification schemes are becoming significant features of international fish trade and marketing, an increasing number of Pangasius producers have followed at least one of the certification schemes recognised by international markets to incorporate environmental and social sustainability practices in aquaculture, typically the Pangasius Aquaculture Dialogue (PAD) scheme certified by the Aquaculture Stewardship Council (ASC). An assessment of the environmental benefit of applying certification schemes on Pangasius production, however, is still needed. This article compared the environmental impact of ASC-certified versus non-ASC certified intensive Pangasius aquaculture, using a statistically supported LCA. We focused on both resource-related (water, land and total resources) and emissions-related (global warming, acidification, freshwater and marine eutrophication) categories. The ASC certification scheme was shown to be a good approach for determining adequate environmental sustainability, especially concerning emissions-related categories, in Pangasius production. However, the non-ASC certified farms, due to the large spread, the impact (e.g., water resources and freshwater eutrophication) was possibly lower for a certain farm. However, this result was not generally prominent. Further improvements in intensive Pangasius production to inspire certification schemes are proposed, e.g., making the implementation of certification schemes more affordable, well-oriented and facilitated; reducing consumed feed amounts and of the incorporated share in fishmeal, especially domestic fishmeal, etc. However, their implementation should be vetted with key stakeholders to assess their feasibility.