7. Interpretation

7.1 Takeaway containers relevant findings

For the takeaway containers, the base case indicates that the reusable container system has potentially lower impacts than the single-use. In the contribution analysis it was observed that the life cycle stages dominating the impacts of the single use container were the raw materials and manufacturing, which when aggregated contributed to 47-81% of the environmental impacts, with exception of land use category where the main hotspot was the distribution stage with 34% of the impacts. While for the reusable container, the impacts are more distributed among the life cycle stages, where the raw materials contribute with 6-59% of the impacts, the manufacturing stage has a range from 9-50%, the use phase shows higher contributions than the single-use, ranging from 9-39%.

The overall results are discussed for each impact categories, by using classification on robustness and terminology of Table 12 of the previous section. The interpretation of results and robustness, are summarised in Table 24:

For acidification, the reusable takeaway container shows significant environmental benefits in the base case (39%) and the sensitivity analyses. It is concluded that the results have a high robustness.

For climate change, total, the reusable takeaway container shows significant environmental benefits in the base case and most of the sensitivity analyses. The results show very significant benefits when the weight of the single use packaging increases (TA2b), when the weight of the reusable packaging decreases (TA1a) and when modeling no impacts during the use phase transportation (TA6). It is concluded that the results have a high robustness.
For freshwater eutrophication, the reusable takeaway container shows significant environmental benefits in the base case and most of the sensitivity analyses. The sensitivity analyses show very significant environmental benefits when the transportation method to the end-user has no impacts or a van is used (TA5 and TA6), by increasing the weight of the single use packaging (TA2b) and by reducing the weight of the reusable packaging (TA1a). The results are considered of high robustness.
For marine eutrophication, the reusable takeaway container shows significant environmental benefits in the base case and most of the sensitivity analyses. The results show major benefits when modeling a no impact transport method in the use phase. It is concluded that the results have a high robustness.
For terrestrial eutrophication, the reusable takeaway container shows significant environmental benefits across the base case and all tested sensitivity analyses. It is concluded that the results have a high robustness.
For ionizing radiation, the reusable takeaway container shows a noticeable benefit compared to the single use system for the base case. Across the sensitivity analyses the reusable system has moderate benefits compared to the single use system in three setups: when the weight of the reusable container is reduced (TA1a), when the single-use weight increases (TA2B) when R2=1 and when B=1 for the reusable system (TA13 and TA14). Additionally, the reusable system shows significant benefits when choosing not to pre-wash the container. The results are considered of high robustness.
For land use, the results show a different trend, as distribution has a higher contribution to the impacts, mainly due to the land use change from road construction. There are moderate environmental benefits from the single use system. The sensitivity shows opposite results (reusable showing higher environmental benefits than single use) in two setups, R2=1 and B=1 (TA13 and TA14). The results show medium robustness, but it must also be considered that the impact category scores with low robustness from the EF 3.1 categorisation (see Table 8).
For ozone depletion, there are marginal benefits for the reusable takeaway container in the base case. However, the sensitivity analysis shows opposite results (i.e., the single use system has lower impacts than the reusable system in this impact category), when increasing the weight of the reusable (TA2a), decreasing the weight of the single use packaging (TA1b), when using car transportation in the use phase and by using incineration as the end-of-life scenario (TA12)
For particulate matter and photochemical ozone formation, the reusable takeaway container shows significant environmental benefits across the base case and all tested sensitivity setups. It is concluded that the results have a high robustness.
For resource use, fossils, there are significant benefits for the reusable takeaway container in the base case. This holds across the sensitivity analyses, except for the sensitivity setups TA1a and TA2b, with the variance of weights, where the impacts of the reusable containers seem to have very significant benefits. It is concluded the results have high robustness.
For resource use, minerals and metals, there are significant benefits for the reusable takeaway containers. This result holds across the sensitivity analyses, except for the cases where van or no impact transportation mode is used for the transportation between the restaurant and the final user (Sensitivity setups TA5 and TA6). The robustness of the results is considered high.
For water scarcity, the single use system shows minor benefits in the base case comparison. In the pre-washing sensitivity analysis, choosing to handwash the container shows a noticeable benefit for the single use system, while by not washing the container shows noticeable benefits in favor of the reusable packaging. Additionally, decreasing the weight of the reusable packaging or increasing the weight of the single use packaging also shows benefits for the reusable container. The robustness of the results is considered medium.

More general the performed sensitivity analyses indicate that:

A variance in the weight reveals the container weight to be one of the parameters that causes a higher change on the results of all impact categories. The weight factor carries a significant impact on the system, as this parameter directly influences various aspects, including material requirements, transportation, and the management of materials at their end-of-life stage. Nevertheless, it is important to consider that even if a reduction in the weight of reusable containers can increase its environmental benefits, it might also result in a reduction of its durability, which might have an impact on the number of times the container is reused, that can lead to a counter-active effect. However, the potential durability of the container was not part of the scope of study.
The break-even point suggests that after 6 uses the reusable container turns to be less impacting than the single use system for most of the impact categories, except for land use, water scarcity, ozone depletion and ionising radiation, which require from 8-14 uses in order for the environmental impacts of the reusable container to be lower than of the single use option.
The CFF values show limited influence on the overall results, but disclose some sensitivity across some impact categories:
- For the adoption of A=1 (cut-off approach) and A=0 (avoided burdens) results of getting no credits and full credit, respectively, of the recycled material in both systems. The effect in the two systems is similar and does not show a difference in the comparison conclusions.
- For the adoption of R3=1 (container treated in incineration at its EoL) and R2=1 (container recovered as recycling) the two systems have the same effect, where no discernible disparities emerge in the overarching conclusion, except for land use. In the case of land use, recycling the container shows contrary results than the base case (the reusable container is indicated to be a better option than the single use container), as more credits are achieved by material recovery and the impacts from incinerating plastics are avoided. Consequently, the reusable system consistently demonstrates reduced environmental impacts. Nevertheless, when analysing the environmental impact for each sensitivity setups relative to the base case, incineration of the containers results in an increase of environmental impacts across a range of impact categories. On the contrary, the treatment involving recycling exhibits a decrease in impacts across most impact categories, except for freshwater eutrophication, ionizing radiation, land use, and ozone depletion.
- For the adoption of B=1 (cut-off approach) the results do not show variations to the base case comparison, except for two opposite results, i.e., lower impacts for the reusable container, for land use and water scarcity.
For the transportation method in the used phase (delivery), the results show the highest benefits when the packaging is transported by methods without combustion of fuel involved, as for example by bike or walking, followed by transportation by van, and lastly by car. The results are influenced by the methodology of the datasets used, as the van impacts are allocated to the van based on the weight of the container and distance (tkm), while the car impacts are allocated by the volume of the container. Nevertheless, the variance in the transportation didn’t change the conclusion of the comparison, meaning that the reusable option still performed as less impacting than the single use one in the same categories as in the base case with any of the three options (with exception of car use in ozone depletion). This represents an uncertainty in the results, as it is believed that using a car specifically for picking and returning a unit of a takeaway container without allocating the impacts per volume would result in higher environmental impacts which could change the conclusions of the study, however this should be further researched.
The alternative showing the lowest impacts is by not washing the container, as no resources are used. This is also the only sensitivity setup of the three evaluated, where the reusable container shows less impacts regarding water scarcity than the single-use alternative. However, this conclusion does not consider the potential risks of bacteria growth, which can be unsanitary. The second method resulting in less impacts is by the use of a dishwasher; this is mainly due to dishwashers being more efficient in the use of water and energy than handwashing.

Table 24 Summary of results of the comparison of the single use takeaway container results against the reusable takeaway container. In case the reusable system shows benefits the comparison cell per impact category is shaded in light green.

EF Impact category	Comparison and difference between base case results as percentage of the reusable	Robustness of the results
EF-Acidification [mol H+ equivalents]	The reusable system shows significant benefits (MU is -39%)	high robustness
EF-Climate change, total [kg CO2-Equivalents]	The reusable system shows significant benefits (MU is -44%)	high robustness
EF-Eutrophication, freshwater [kg N equivalents]	The reusable system shows very significant benefits (MU is -47%)	high robustness
EF-Eutrophication, marine [kg P equivalents]	The reusable system shows significant benefits (MU is -41%)	high robustness
EF-Eutrophication, terrestrial [mol N equivalents]	The reusable system shows significant benefits (MU is -39%)	high robustness
EF-Ionising radiation, human health [kBq U235 equivalents]	The reusable system shows noticeable benefits (MU is -17%)	high robustness
EF-Land use [pt]	The single use system shows moderate benefits (MU is +27%)	medium robustness
EF-Ozone depletion [kg CFC11 equivalents]	The reusable system shows marginal benefits (MU is +3%)	medium robustness
EF-Particulate matter [disease incidence]	The reusable system shows significant benefits (MU is -37%)	high robustness
EF-Photochemical ozone formation - human health [kg NMVOC equivalents]	The reusable system shows significant benefits (MU is -38%)	high robustness
EF-Resource use, fossils [MJ]	The reusable system shows significant benefits (MU is -46%)	high robustness
EF-Resource use, minerals and metals [kg Sb equivalents]	The reusable system shows significant benefits (MU is -37%)	high robustness
EF-Water scarcity [m3 world-Eq deprived]	The single use system shows minor benefits (MU is +6%)	medium robustness

7.2 E-commerce relevant findings

7.2.1 Single use plastic (SUPL) and reusable system

The base case comparison of the single use plastic system and the reusable system shows that the single use plastic system predominantly has lower impacts. In both systems the environmental hotspots occur in the upstream stage, i.e., raw material extraction and manufacturing and distribution life cycle stage. Environmental impacts in the single use system are predominantly driven by the raw material, followed by the distribution. For the reusable system the trend is similar, yet manufacturing has a relatively more dominant role. Further the use phase has a higher impact due to more transports in the reverse logistics. As both packaging systems are made of plastic the environmental profiles of both systems are similar.

Together these upstream life cycle stages, i.e., raw material extraction and manufacturing and distribution contribute to between 59% and 97% of the impact for the single use system and between 57% and 96% of the impact of the reusable system.

Where relevant the overall results are discussed for each impact category, using classification on robustness and terminology of Table 12 of the previous section. The interpretation of results and robustness, are summarised in Table 25:

For most impact categories the base case comparison indicates very significant environmental benefits for the single use system (SUPL), additionally showing high robustness across all impact categories. Thus, they are not discussed in detail.

The following two impact categories fall out of the overall observation.

For Resource use, fossils the base case comparison has very significant environmental benefits for SUPL (59%). In one sensitivity comparison (C: Manufacturing material raw material recycled plastic (EC3.1), i.e., if the reusable packaging is made of recycled material (R1=1) and the single use packaging is made of virgin material (R1=0)) the sensitivity analysis shows opposite results. This result is expected (part of the sensitivity definition) but gives the category a medium robustness.
For Water scarcity the base case comparison has significant environmental benefits for SUPL (47%). However, the trend does not change across the impact categories.

Table 25 Summary of the comparison “Single use plastic bag system” against “Reusable bag system”. In case the reusable system shows benefits the comparison cell per impact category is shaded in light yellow.

EF Impact category	Comparison and difference between base case results as percentage of the reusable	Robustness of the results
EF-Acidification [mol H+ equivalents]	The single use system shows very significant benefits. (-59%)	high robustness
EF-Climate change, total [kg CO2-Equivalents]	The single use system shows very significant benefits. (-54%)	high robustness
EF-Eutrophication, freshwater [kg N equivalents]	The single use system shows very significant benefits. (-67%)	high robustness
EF-Eutrophication, marine [kg P equivalents]	The single use system shows very significant benefits. (-58%)	high robustness
EF-Eutrophication, terrestrial [mol N equivalents]	The single use system shows very significant benefits. (-59%)	high robustness
EF-Ionising radiation, human health [kBq U235 equivalents]	The single use system shows very significant benefits. (-68%)	high robustness
EF-Land use [pt]	The single use system shows very significant benefits. (-74%)	high robustness
EF-Ozone depletion [kg CFC11 equivalents]	The single use system shows very significant benefits. (-81%)	high robustness
EF-Particulate matter [disease incidence]	The single use system shows very significant benefits. (-61%)	high robustness
EF-Photochemical ozone formation - human health [kg NMVOC equivalents]	The single use system shows very significant benefits. (-56%)	high robustness
EF-Resource use, fossils [MJ]	The single use system shows very significant benefits. (-60%)	medium robustness
EF-Resource use, minerals and metals [kg Sb equivalents]	The single use system shows very significant benefits. (-69%)	high robustness
EF-Water scarcity [m3 world-Eq deprived]	The single use system shows significant benefits. (-48%)	high robustness

7.2.2 Single use paper (SUPA) and reusable system

The base case comparison of the single use paper system and the reusable system indicates that the systems have benefits in selected impact categories, not one is predominantly better. In both systems the environmental hotspots occur in the upstream stage, i.e., raw material extraction and manufacturing and distribution life cycle stage. Environmental impacts in the single use system are predominantly driven by the raw material, followed by the distribution. For the reusable system the trend is similar, yet manufacturing has a relatively more dominant role. Further the use phase has a higher impact due to more transports in the reverse logistics.

Together these upstream life cycle stages, i.e., raw material extraction and manufacturing and distribution contribute to between 31%-91% of the impact for the single use system and between 57%-96% of the impact of the reusable system.

For Acidification, the reusable system has environmental benefits across the base case comparison and all sensitivity scenarios. The base case comparison has moderate environmental benefits. In the sensitivity case where the SUPA is modelled with only the kraft paper dataset (B: Manufacturing material, raw material only kraft paper (EC3.2)) the relationship changes to a marginal benefit for the SUPA (medium robustness).
For Climate Change, total, there are moderate environmental benefits for the SUPA system. The reusable system has 25% higher impacts than the SUPA system in the base case comparison. In the sensitivity analysis, three scenarios merit consideration, as they deviate to the base case results:
- D: CFF 100% recycling R2= 1 (EC9); in which both packages are 100% recycled;
- D: Energy credit B=1 (EC13); in which no credits are given for waste incineration.
The results in this impact category are dominantly influenced by the virgin input and avoided material or energy production. Overall, this impact category has a medium robustness.
For Eutrophication, freshwater, there are very significant environmental benefits for the reusable system. The SUPA has in all scenarios a more than 350% higher impact, due to different raw materials (high robustness).
For Eutrophication, marine, there are very significant environmental benefits for the reusable system. The SUPA has in all scenarios a more than 150% higher impact, due to different raw materials (high robustness).

For Eutrophication, terrestrial, there are very significant environmental benefits for the reusable system. The SUPA has in all scenarios a more than 63% higher impact, due to different raw materials (high robustness).
For Ionising radiation, human health, there are very significant environmental benefits for single use system in the base case. This category is influenced by the material credit for the paper packaging. The following two scenario cases show different results.
- D: CFF A=1 (cut-off) (EC6); in both systems the recycling impact is not considered and no material credits are given
- D: CFF 100% incineration R3=1 (EC8); only energy credits and no material credits
As the results are not consistent throughout all considered scenarios in this impact category, the comparison between the two systems slightly depends on underlying assumptions (medium robustness).
For Land use, there are very significant environmental benefits for reusable system in the base case. The SUPA has in all scenarios a more than 1500% higher impact, due to different raw materials (high robustness).
For Ozone depletion, there are very significant environmental benefits for reusable system in the base case. The base case comparison shows 165% higher impact for the SUPA system. The following sensitivity analysis deviate the base case results (medium robustness) the impact is reduced to a marginal difference:
- B: Manufacturing material raw material only kraft paper (EC3.2); the reusable system has only a moderate environmental benefit if the paper packaging only consists of kraft paper
- D: Manufacturing material raw material (EC3); as above the raw material of the paper bag influences the relationship. With the tested alternative the difference is not so high
For Particulate matter, there are significant environmental benefits for the reusable system in the base case (the reuse system has 44% lower impacts than SUPA in the base case). The trend is consistent across all sensitivities (high robustness).
For Photochemical ozone formation, there are significant environmental benefits for the reusable system in the base case (the reuse system has 43% lower impacts than SUPA in the base case). The trend is consistent across all sensitivities (high robustness).
For Resource use, fossils, there are significant environmental benefits for single use system in the base case (the reuse system has 55% higher impacts than SUPA). This holds across the sensitivity tests, except for the following sensitivity (medium robustness) where no virgin plastic material is used. The results indicate that the paper production requires more fossil resources higher the production of recycled plastic, which is not surprising. As the base case for all product systems are virgin raw materials the variation in the CFF factor A does not influence this results much.
- C: Manufacturing material raw material recycled plastic (EC3.1); significant higher impacts of the SUPA system when the reusable system is produced with recycled plastic;
For Resource use, minerals and metals, there are moderate environmental benefits for single use system in the base case (SUPA has 33% lower impacts than the reusable system). The environmental benefits for the reusable system are consistent throughout all considered models in this impact category, and the comparison between the two systems is not dependent on underlying assumptions (high robustness).
For Water scarcity, there are minor environmental benefits for the reusable system in the base case. Changes in material weight and allocation methods change the results (medium robustness).

Table 26 Summary of the comparison “Single use paper bag system” against “Reusable bag system”. In case the reusable system shows benefits the comparison cell per impact category is shaded in light green.

EF Impact category	Comparison and difference between base case results as percentage of the reusable	Robustness of the results
EF-Acidification [mol H+ equivalents]	The reusable system shows moderate benefits. (22%)	medium robustness
EF-Climate change, total [kg CO2-Equivalents]	The single use system shows moderate benefits. (-25%)	medium robustness
EF-Eutrophication, freshwater [kg N equivalents]	The reusable system shows very significant benefits. (417%)	high robustness
EF-Eutrophication, marine [kg P equivalents]	The reusable system shows very significant benefits. (566%)	high robustness
EF-Eutrophication, terrestrial [mol N equivalents]	The reusable system shows very significant benefits. (91%)	high robustness
EF-Ionising radiation, human health [kBq U235 equivalents]	The single use system shows very significant benefits. (-118%)	medium robustness
EF-Land use [pt]	The reusable system shows very significant benefits. (2756%)	high robustness
EF-Ozone depletion [kg CFC11 equivalents]	The reusable system shows very significant benefits. (165%)	medium robustness
EF-Particulate matter [disease incidence]	The reusable system shows significant benefits. (44%)	high robustness
EF-Photochemical ozone formation - human health [kg NMVOC equivalents]	The reusable system shows significant benefits. (43%)	high robustness
EF-Resource use, fossils [MJ]	The single use system shows very significant benefits. (-55%)	medium robustness
EF-Resource use, minerals and metals [kg Sb equivalents]	The single use system shows significant benefits. (-33%)	high robustness
EF-Water scarcity [m3 world-Eq deprived]	The single use system shows noticable benefits. (-10%)	medium robustness

7.3 Discussion of assumptions and limitations

The results are influenced by methodological decisions, assumptions, and simplifications conducted along the study. This section collects the assumptions and limitations embedded in the reported life cycle assessment.

Reuse rate – Number of uses

It is evident that the choice of the number of uses influences the results of the reuse system. The studied case studies adopted a reuse rate of 90% (10 uses) for the takeaway system and 75% (4 uses) for the E-commerce packaging. In conversation with private operators no coherent statistic could be developed, further no default value could be retrieved from the plastic LCA method, (Nessi, et al., 2021, section 4.4.11.5). No publication could be found with information regarding average rotation timeframe of reusable takeaway or e-commerce packaging, average lifespan of these or evaluation of available reuse scheme. Further research is finally envisaged for evaluating number of uses of reusable systems in comparative works between single-use and multiple-use products. The factor was studied by a breakeven analysis to give an indication which reuse rates have to be achieved to reduce the environmental burden of packaging systems through reuse.

Functional Limitations of the studied Packaging Solutions

The aim of this study was to examine and compare the performance of single-use and reusable packaging solutions, specifically for food takeaway and clothing e-commerce. In this evaluation, the primary function of these packaging solutions, containing and transporting goods, was the main focus. Secondary usage, such as storage of food leftovers or returning online purchased clothes, were not included in this analysis. Furthermore, additional functionalities such as print/advertising and enhanced protection were also not considered.

Both single-use and reusable solutions have different functional attributes and a direct comparison of all potential aspects of their functionality is not feasible. This is a fundamental limitation recognized by the authors. The study assumed packaging solutions were always used in their conventional applications as takeaway containers or e-commerce clothing packages. Differences in function should be remembered when applying this study’s results to policy-making decisions.

Additionally, the reuse rate is the only parameter which can be considered to evaluate the performance of the studied systems in the functional unit. Parameters such as breakage or damaged good were assumed to be part of the reuse rate, as if the package is damaged it would be not used again. Future studies may expand on this by considering the secondary uses of packaging, the additional functionality that packaging can provide and further performance parameters. This could enable a more holistic understanding of the potential environmental impacts and benefits offered by different packaging solutions. This study provides a solid basis and methodology for such future research, providing an understanding of the broad comparison between generic single-use and reusable packaging solutions.

Comparison of generic products

The packaging solutions represent generic products as available on the market and are entirely modelled with secondary data. As such the life cycle of the packaging solutions are modelled with average specifications and with generic material input, a generic production process and country/ region specific electricity mixes. Real products on the market likely will use materials, processes, or electricity mixes that have an environmental profile different than the respective generic data. Different sensitivity results were calculated, i.e., weight differentiations for all systems and in case of E-commerce where the systems use different materials also the recycled content (value R1) and datasets of the materials were tested (EC3.1 and EC3.2). Besides these, no sensitivity result could be calculated due to modelling limitations regarding the available generic background data. This limitation is however in line with the stated goal of the study, as generic products could be represented.

It should be noted that real-life products may use different materials, processes during the life cycle or electricity mixes with varying environmental profiles. Therefore, the study’s results should be viewed as indicative of a generic application, rather than specific real-world instances.

Use of secondary data

The models within this study were built upon the ecoinvent 3.9.1. database which represents the most recent and available database.

To inform the models and available packaging solutions the market was screened, but the processes were modelled with generic processes. Also studies in literature have based their models and assumptions on secondary data for the packaging solutions (as in this study), a potential step forward would be collecting more primary data at industry level. This might be relevant in future works.

Use of Plastic LCA method

Where relevant for this study default values followed guidance of the Plastic LCA method (Nessi, et al., 2021). Assumptions regarding the distribution and use phase, e.g., distances, mode of transport and allocation procedures are based on an official methodology, creating more robust assumptions. However, these assumptions also contribute to the uncertainty of the study, as these are parameters that vary depending on the user.
The study does not claim to be compliant to the Plastic LCA method, but just informed in some assumption for the foreground system. Specific product systems in reality might have different foreground and background systems. This limitation is however in line with the stated goal of the study, as generic products could be represented.

Use of the CFF as allocation method

It should be noted that the use of the CFF, as well as the use of its default values (e.g., A, B), could have relevant effects on the overall results in comparative assertions, especially when considering recycling and incineration EoL treatment. The use of default values may lead to controversial results, as, in general and by applying default values, EoL treatment via recycling shows, in general, higher emissions than treatment via incineration (by considering credits of avoided material, as well as avoided energy production). This is for both the A factor influencing recycling and the B factor influencing incineration and the connected material and energy credits. As pointed out in literature it has the main risk of “giving incorrect incentives”: the CFF “assigns the full net benefits of energy recovery to incinerated products” while it assigns only 50% of net environmental benefit of recycling. Approaches for calculating more appropriate B values have been proposed.

See, e.g., Tomas Ekvall report (2021), available at the Swedish Life Cycle Center Website: https://www.lifecyclecenter.se/publications/factor-b-in-the-circular-footprint-formula-abstract-setac-europe-2021/

As the later is not a standard procedure in sensitivity analysis applied to the CFF, and as it is still part of the ongoing research, the impacts of these factors were studied by choosing the extreme values of A=0 and A=1 as well as B=1 for sensitivity analyses. This aspect merits further investigation to assign proper burdens for EoL treatment, and improvement on the definition of geographically adjusted default values in the CFF might deserve further improvement in future works.

The CCF was implemented for the main flows crossing the system boundaries. Besides these the model builds upon datasets from the Ecoinvent cut-off system model and the allocation within these datasets was not adjusted to the CFF.

Biogenic carbon emissions

In LCAs two approaches that consider biogenic carbon cycle could be taken. The first approach considers biogenic carbon dioxide removal and release. This approach is taken, for example, in the EN 15408 methodology, where all biogenic inputs and outputs elementary flows are accounted. Therefore, biogenic carbon dioxide uptake is considered as credit, and biogenic carbon dioxide, as well as biogenic methane, are considered as impacts. The second approach considers only biogenic emissions to air other than CO₂ (e.g., methane). This approach is used in the EF 3.1 methodology based on IPCC 2013 report (AR5). Since this study is presented via EF 3.1 impact categories, it includes only biogenic methane emissions in the Climate Change biogenic impact category.

For evaluating environmental burdens (LCIAs following EF 3.1) of paperboards, only the fossil carbon emissions are considered. This approach builds upon the assumption of a managed forest landscape that maintains or increases the carbon stock, i.e., the biogenic carbon emissions are considered to be balanced by the uptake of the growing biomass.

Geographical choices

The geography for the manufacturing phase of the products was assumed to be taking place in a European context for the single use and reusable systems. However, this is an assumption which is not always the case, as many of these types of products are supplied from the Asian market. This geographical location was assumed to be the same for both systems to avoid introducing any bias in the results.

Choice of datasets

The datasets were chosen from the selected database following the developed data quality requirements (cf. section 4.2.5). The best available datasets were chosen. The LCI tables may be found in Appendix G (takeaway) and Appendix H (e-commerce). However, the LCI of the chosen datasets is not included as the datasets are licensed by the Ecoinvent database.

Impact categories

This study assesses the potential environmental impact solely according to the EF 3.1 impact assessment method, as was preconditioned by the setup of the study by the Nordic Council of Ministers. All value choices and subjective choices embedded in this method are thus carried on to this study. For more detail on the method the reader may be referred to the European Platform on LCA (EPLCA).

It should be pointed out that Life Cycle Impact Assessment (LCIA) methods used within this study possess their own inherent robustness. As a corollary, discrete differences in diverse indicators from these methods are not directly comparable. Therefore, they should be interpreted cautiously and within the proper context.

According to the ISO 14044, no normalization and weighting should be done in LCAs of comparative nature. Therefore, it must be noted that each of the impact categories has different units and metrics and cannot be compared between each other. The four impact categories of robustness level III that are presented should be considered carefully, i.e., the results for Land Use, Water Use, Resource Use – minerals and metals, and Resource use – fossils.