Review of new design approaches to achieve Zero Waste strategies

 

Revisión  | Review

Marta Gómez Martínez

Ricard Vila Studio, Baixada del Calot 3-7, Igualada, design.martagomez@gmail.com

Received: 19 March 2021 | Accepted: 18 May 2021 | Published: 29 June 2021

DOI: https://doi.org/10.25267/P56-IDJ.2021.i1.2

------------------------------------------------------------------------------------------------------------------

Introduction

In recent decades there has been a noticeable increase in concern about the origin, usefulness and subsequent disposal of products. Both in terms of the production process and in terms of waste, packaging and the energy needed to manufacture them. In fact, "the search for innovation reoriented towards sustainability is becoming paramount", according to Asencio (2020). In this context, the carbon footprint is a highly sensitive indicator that makes it possible to measure the consequences of climate change by deepening our knowledge of greenhouse gases, as Schneider and Samaniego (2009) explain.

The various reports of the Intergovernmental Panel on Climate Change (IPCC) since the beginning of the millennium have warned the population of the global risk it faces if the level of overexploitation of available resources continues, as Terradas (2009) points out.

According to the Global Carbon Project, the increase of CO2 in the atmosphere followed a faster trend between 2000 and 2008 than the worst hypothesis of all those used by the IPCC. Terradas thus underlines the importance of sustainable development as the future of resource consumption.

This process of awareness of sustainable development was preceded by important negotiations, treaties and agreements that emerged at the end of the 20th century. Specifically, the Uruguay Round, the eighth round of negotiations under the General Agreement on Tariffs and Trade (GATT), triggered the Rio de Janeiro Earth Summit in 1992, as mentioned by the World Trade Organization (WTO), which dealt with the environment and sustainable development.

This important impact on society has generated as a result, at international level, the creation of a set of standards that cover the aspects of how to establish an effective Environmental Management System (EMS), the ISO 14000. This set of standards originates from ISO, an independent non-governmental international organization with 165 national standardization bodies that, since 1946, brings together experts to share knowledge and develop voluntary, consensus-based, market-relevant International Standards. They support innovation and provide solutions to global challenges (International Organization for Standardization [ISO], n.d.).

The discovery of plastic at the beginning of the 20th century has modified consumption habits and, consequently, has escalated the production of plastic without considering the life cycle, without taking into account the damage and the consequent problems that humanity and the future of the planet are currently facing: the scarcity of resources and the significant increase in CO2 emissions. This problem, which has arisen from the waste of resources and the excessive consumption of non-renewable resources, can be transferred to the different sectors involved in the manufacture of products.

According to Professor Betts of the Mauna Loa Observatory in Hawaii, the increase of CO2 in the atmosphere, caused by humans, is accelerating, so restoring and slowing down this trend will force the reduction of global emissions to zero (Quoted in Madge, 2021).

Starting the review from a globalized vision, packaging is projected as a generalized sample of the current situation in recent decades: an increase in excessive production, without considering the possibility of a transversal alternative to the waste of materials. As a result, more and more unnecessary packaging is being produced, the inappropriate consequence of which is to aggravate the existing difficult environmental situation.

Raw materials are not only the main focus of attention in this study on eco-design strategies. The use of electricity, water and emissions in manufacturing, as well as the transportation of such products, together with waste and littering, all add to the carbon footprint.

For its part, the main objective of good design is to study these characteristics to reduce or achieve Zero Waste as referred to by J.M. Simon, J. McQuibban and P. Condamine (2020).

Approaching the subject from research in the field of materials is committed to the use of innovation and technology to address this issue, leading not only to eco-efficient products but also to innovative solutions in the field of design and materials, as pointed out by the World Design Organization [WDO] (2020).

To continue with the development of this review, three main objectives are involved. First, the study of traditional vs. new design models in reference to the circular economy and Zero Waste. Secondly, the analysis of the favorable points of the new models proposed. Finally, a new hypothesis on the future of eco-design strategies is proposed.

The importance of the problem developed in this review, described above, raises the future of design today to be able to manage existing resources, as well as the reduction of emissions and harmful waste both for the planet and at the cellular level.

The motivation to carry out this work is sequenced by the misuse and exploitation of resources that has been done since the beginning of industrialization falling into mistakes that should be avoided. By learning the methods of conceptualization, development, manufacturing, distribution, maintenance and end of life, an optimal circular economy can be achieved.

The present work is made up of different sections. First, a review methodology is established by explaining the methodology used to carry out the review. Next, the development of the objective is presented by exposing the underlying points of the main theme of the main objective contrasting the different perspectives and issues. Once exposed, the results and discussion are presented, based on the formulation of the results of the different points of view exposed and the analysis of the results, respectively. Finally, the main conclusions and the objective resolution of the analysis of the results and discussion are established.

Methodology of the review

In order to develop the subject matter addressed in this review, the bibliographical methodology defined in the following points presented by the author will be taken into account:

Sources, selection criteria and limits.

The sources consulted are defined below:

• Paper journal articles
• Electronic journal articles
• Newspaper articles
• Conference papers
• Research data
• Legislation
• Paper books or book chapters
• Books or chapters of electronic books
• Leading websites in the sector
• Electronic doctoral theses

The selection criteria chosen are (1) the relevance and quality of the source, (2) the scientific quality through different aspects (title and author/s, summary and results), (3) the methodological validity of the review, and (4) the credibility.

Previously described sources between 2001 and 2021 will be studied.

Development of the objective

The United Nations Development Programme contributed in 2015 to protect the planet among other objectives of the so-called Sustainable Development Goals (SDGs) adopted by all UN Member States.

In order to achieve Zero Waste strategies and an effective circular economy, SDGs 9 and 12 have a major impact in this area as mentioned by the United Nations Development Programme (n.d.):

Goal 9 focusing on industry, innovation and infrastructure identifies the need for technological advances to find permanent solutions to economic and environmental challenges, and the promotion of energy efficiency. As well as other models to facilitate sustainable development through sustainable industries.

Goal 12 on responsible production and consumption mentions that: "To achieve economic growth and sustainable development, it is urgent to reduce the ecological footprint by changing the methods of production and consumption of goods and resources. (...) The efficient management of shared natural resources and the way in which toxic waste and pollutants are disposed of are vital to achieving this goal. It is also important to encourage industries, businesses and consumers to recycle and reduce waste (...)".

More and more people are committed to the Zero Waste strategy, not only in the area of design and manufacturing. Globally, a collective thinking has been generated about the different opportunities that reuse and recycling can offer, from a domestic scale environment in which a person reuses glass bottles to a corporate level in which more and more companies are dedicated to giving a function to the waste that others do not use as Daigneau (2017) indicates.

Quoting Garcia (2020): "the Zero Waste concept (...) refers to the practice of generating as little waste as possible, meaning any waste that is not reusable, compostable or recyclable. This term was born in the 1970s and re-emerged strongly at the beginning of this millennium".

In order to continue the study in the field of strategies to achieve the circular economy it is necessary to define the following terms that comprise the research fields of this review: ecological footprint, carbon footprint and eco-design.

- Ecological footprint

The ecological footprint, as mentioned by Schneider and Samaniego (2009): assesses the amount of water and land biologically essential to obtain the necessary resources that an individual or population needs for consumption and to absorb its waste, using existing technology and resource management practices.

- Carbon footprint

The carbon footprint measures the impact of individual, collective, eventual and product activities of all greenhouse gases on the environment. In other words, it shows the amount in tonnes or kilograms of carbon dioxide equivalent of greenhouse gases, generated from the burning of fossil fuels for energy production, heating and transport among other processes, produced on a day-to-day basis. (Schneider and Samaniego, 2009)

- Ecodesign

Ecodesign is the set of actions focused on the environmental improvement of a product from the initial design stage, through the improvement of the function performed, the choice of less impacting materials for its manufacture, the use of processes with minimum environmental impact, the improvement in the transport and use of the product, and the reduction of impacts in the final distribution of the product" (Aranda and Zabalza, 2010).

As mentioned by Schneider and Samaniego, the individual carbon footprint is made up of the primary and secondary carbon footprint, which refer respectively to the measure of direct CO2 emissions from fossil fuels and the measure of indirect CO2 emissions from the entire life cycle of the products we consume, i.e. the CO2 emissions from the production processes of goods and services.

According to González, Gilberto and Vargas-Hernández (2017), in the Linear Economy, companies have been following a production and consumption model for more than 150 years of industrial evolution, where they are exclusively dedicated to extracting natural resources from the environment to obtain consumer products and that at the end of their life cycle, these products are discarded and transformed into waste that is not reused.

All this results in the pollution of ecosystems and the deterioration and overexploitation of natural resources.

Prior to the Rio de Janeiro Summit (Brazil) in 1992, which marked the beginning of sustainable development, different alternatives to the Linear Economy were proposed, as shown in Table 1 (González, Gilberto and Vargas-Hernández, 2017):

Table 1. Precursors of the Circular Economy. | Source: González, Gilberto and Vargas-Hernández (2017)

Model or philosophy	Author(s) and year	Features
Permaculture	Mollinson and Holmgren, late 1970s	Conscious design and maintenance of productive agricultural ecosystems. Applied and integrated ideas and concepts from modern innovations in organic farming and traditional agriculture.
Industrial ecology	Frosch, R.A. and Gallopoulos, N.E. 1989	It contributed to the achievement of sustainable development. It is known as the science of sustainability because of its interdisciplinary character and because its principles can also be applied to services.
The Natural Step	Robèrt, K. 1989	Organisation implemented in a dozen countries. The use of resources must be efficient and consistent with human needs.
Cradle to Cradle (C2C)	McDonough and Braungart, 90’s	They classified materials into technical and biological.They were inspired by the transformation of the biosphere as a model for the development of the transformation of the flow of industrial processes into the technosphere.
Regenerative Design	Lyle, J.T. 1994	He determined that any system, starting with agriculture, can be organised in a regenerative way, emulating the functioning of ecosystems, where products are created and interact without producing waste.
Natural Capitalism	Lovins, L. H., Lovins, A. and Hawkens, P. 2007	It recognised natural capital and human capital, shifting from a consumer to a service economy and reinvested the profits in ensuring the conservation of natural resources.
The Performance Economy	Stahel, W. 2010	He put forward the vision of a loop economy and the consequent impact on job creation, economic competitiveness, resource savings and waste prevention.
Blue Economy	Pauli, G. 2011	It was inspired by the earth, with points in common with C2C models and Biomimicry. It rejected the elitist attitude of the green economy that offered environmentally friendly products that preserved the environment but were only accessible to a wealthy and unsustainable elite.
Biomimicry	Benyus, J. 2012	It took artificial mechanisms as a basis, synthesised natural processes and thus solved human problems. It was based on three principles: 1-      Nature as a model 2-      Nature as a measure 3-      Nature as mentor

Focusing the study on different perspectives, it starts from the different parts that make up the design and manufacturing process alluding to Clocowen's Wheel of Sustainability (Contreras, Owen, Cloquel, Cloquel and Segundo, 2012). The following parts of the study will be based on the development of new materialisation concepts, the selection of low impact materials and reduction of material use, then the selection of low impact materials and reduction of material use, then the study will focus on the optimisation of production techniques and optimisation of distribution systems, followed by the reduction of environmental impact during use and the optimisation of product life, ending with the optimisation of the end of life of the system.

1. Development of new materialisation concepts

To achieve a circular economy through Zero Waste, not only the late stages of product development have to be considered. This process is addressed from the beginning of conceptualisation for new product designs or redesigns that can thrive towards a more sustainable economy.

Zero Waste can be achieved through innovations for a circular economy. This can be achieved from the very beginning of such a process, through the conceptualisation of products and/or packaging using a single material, optimising both product design and size. Developing the integration of all or most functions, if possible, can lead to the minimisation of materials and production techniques (Contreras et al., 2012).

An example of this unification of functions is the current increase in the combination of packaging and product in which much of the packaging sector is focused, researching and studying the different possibilities towards a more optimal, cleaner and environmentally friendly result.

At Innoveit 2017 (Banks, M., 2017) held in Budapest together with the European Institute of Innovation and Technology, the London-based start-up Skipping Rocks Lab stood out within this field, from its premise: "don't recycle water packaging, just eat it" (Montes, 2017) whose transgressive idea defines a new way of packaging water by replacing conventional containers with a containing membrane obtained from the esterification of water, this process (commonly used in molecular cuisine) is applied in this case by building a container from algae, chlorine and calcium capable of containing 50 ml of water, in which this is in the form of a bubble discarding the idea of a bottle.

However, this approach generates a series of problems in the field of food, including the way of transporting and complying with health regulations in this type of product, as shown in Figure 1 with bulk foods, which partially reduces the use of packaging.

Figure 1. Partial reduction of packaging use through bulk food.|  Source: Pexels.

2. Selection of low-impact materials and reduction of material use

In recent years, innovation has shifted from waste management to resource management, thus processing the change of mindset not only on the waste level but also on the raw material scarcity in which mankind is involved (J.M. Simon et al., 2020).

This has allowed a development in the different existing conceptions in reference to the improvement and refinement of the methods of recovery or creation of new materials.

Gradually, among these new materials, the incorporation of experimental materials made from waste, food scraps or waste is gradually being visualised.

Remix El Barrio (2021), a proposal by MATERFAD proposes a new design with biomaterials, "in the last 30 years, the production of plastic has increased by 620%". Remix El Barrio claims the need for new models and techniques to innovate when it comes to what is commonly referred to as "waste". In addition to these new materials, there are new innovations in biodegradable materials.

"In recent decades there has been a remarkable boom in the use of polymeric materials for a large number of applications. The sector where the greatest involvement of these new techniques has been observed is the packaging sector". (Giménez, Cabedo, Feijoo, Fukushima and Lagarón, 2008).

Biodegradable polymer or clay nanocomposites are introduced as a biosustainable alternative to conventional materials, mostly present in the area of packaging, as Giménez et al. (2008) explain.

The SINSOST project developed by the Instituto Tecnológico del Embalaje, Transporte y Logística (ITENE) focuses on the research of new biodegradable materials with multi-properties as shown in figure 2, forming a sustainable alternative for the packaging sector and directing the focus of the future to the sustainable economy.

Funded by the Valencian Institute for Business Competitiveness (IVACE), the SINSOST project has two objectives: "to improve the final properties of materials based on paper and cardboard with biodegradable cellulose nano-reinforcements and, on the other hand, to improve the final properties of materials based on biodegradable polymers additivated with nanostructured reinforcements". (Instituto Tecnológico del Embalaje, Transporte y Logística [ITENE], 2018).

Figure 2. Research into new biodegradable materials. | Source: Pexels.

As ITENE (2018) mentions, in this first strategy in the research of new biodegradable materials, the development of new cellulose nanofibres (CFMs), obtained through waste from agri-food industries (by means of tomato plant remains and sawdust), has been addressed.

3. Optimisation of production techniques

The production of greenhouse gases in excess of the planet's assimilation capacity together with ecological limitations, the increase of depleted natural and energy resources, as well as overexploitation together with other factors determine a series of unsustainable situations at the present time.

The aim is to achieve responsible production and consumption with the described characteristics and to make use of a sustainable industry through the available innovation and infrastructure. Thus enabling an increase in the social responsibility of cities and communities to achieve these goals and achieve sustainability.

To this end, an evaluation of the parameters that entail a decrease towards sustainability in the manufacture of products is proposed, based on an improvement of the aptitude based on the different approaches found in the productive processes.

As Vergara (2018) points out, by assessing the environmental impact, the main limitations of these processes can be deduced, which is why a sustainability report should analyse a model that reduces this impact to achieve zero impact.

By carrying out an evaluation using the following indicators, it is possible to achieve a development in terms of production in order to achieve clean production, therefore it is necessary to study the following parameters as shown in Table 2 (Vergara, 2018):

Table 2. Indicators in the optimisation of production techniques. | Source: Own elaboration

Environmental Capital Indicators	Economic Capital Indicators	Indicators of Social-Human Social-Human Capital Indicators
-          Renewable energy -          Fossil energy -          Material and natural resources -          Water, air and land quality -          Water resources	-          Infrastructure Investment -          Per capita income. Production of goods and services -          Production of raw materials -          Products generated by PMP -          Capital	-          Demographics -          Consumption capacity -          Social organisation -          Satisfaction of needs and wants

These sustainability indicators, as Vergara argues, make it possible to identify the potential for sustainable development at the national level by developing industrial products within the framework of the sustainability of its resources.

In the manufacture of products, not only the production itself is highlighted, but also the manufacture of the machinery necessary to carry out these processes must be included. Therefore, taking on more machinery and processes increases the negative impact on the production of a single end product.

There is worldwide concern about the high consumption of fossil fuels, climate change, global warming and the short and long term consequences. As mentioned above, the European Union as well as the United Nations have laid the foundations for the improvement of these objectives.

4. Optimisation of distribution systems

The consumption of local and proximity products significantly reduces the environmental impact, contributing to environmental well-being by saving on transport and intermediaries that increase the use of fossil fuels and the production of greenhouse gases, by choosing the cleanest transport methods and by ensuring the optimisation of packaging.

This requires the local development of collection, storage, processing, and distribution systems, by product as mentioned by Balboa and Somonte (2014).

Tomorrow Machine is an example to follow in this area. Created to rethink the traditional packaging business in the food industry, this Swedish company, through the combination of innovation, technology, sustainability and material science, develops the future of packaging (Tomorrow Machine, n.d.).

Through decomposition, dissolution or biodegradable materials, they are committed to a more sustainable design by looking for substitutes to plastic.

5. Reducing environmental impact during use

By designing the product from the first stage of conceptualisation, the correct use of the object can be guaranteed, achieving a reduction in environmental impact through low or zero energy consumption, substituting energy sources so that they are clean or renewable, as well as reducing the amount of consumables.

6. Optimising product life

Making a product durable over time is another technique to reduce impact.

Currently, a large number of electronic products are subject to planned obsolescence, which generates millions of tonnes of electronic waste every year, deliberately reducing the useful life of the product, which is a serious environmental problem for the planet. The ISSOP seal certifies that companies respect and prioritise the production of environmentally friendly goods and services (Acciona, n.d.).

In the same way, achieving a high ease of maintenance and repair reduces the manufacture of new products, thus mitigating the environmental impact. Furthermore, by allowing the replacement of components, reuse or recycling of components can be taken into account.

7. System end-of-life optimisation

At the end of the product's useful life, it can be reused, recycled or reconditioned. This requires that the product has been designed for these different options and that they have been taken into account throughout the process, thus achieving the so-called "Zero Waste".

The separability of the different parts that make up the product is a decisive key factor in this phase. By allowing the separation of the components, the reparability and/or recovery of the rest of the product or of the affected parts can be achieved, as Ezpeleta, Justel, Zubelzu, Bereau and Elizburu (2019) refer to, reducing the generation of waste and, if possible, achieving remanufacturing.

On the other hand, a change in the mentality of the population is essential so that when the product reaches the end of its useful life it can be deposited in the correct place so that the aforementioned can be carried out.

A previously established planning where the use of the different strategies mentioned above and the good management of resources are the focal points of the project can make sustainable development towards a circular economy possible by achieving Zero Waste products.

Results

By compiling the results obtained from the strategies analysed and studied, Table 3 is elaborated:

Table 3. Results obtained from the review of sustainable strategies. Source: Own elaboration

Life Cycle Phase	Strategies	Examples
Development of new materialisation concepts	-        Functional integration -        Functional product optimisation	-    Skipping Rocks Lab
Selection of low-impact materials and reduction of material use	-        Use of clean, renewable, low-energy and recycled materials	-        Remix El Barrio -        Biodegradable polymer/clay nanocomposites -        SINSOST Project
Optimisation of production techniques	-        Use of alternative production techniques -        Reduction of production process steps -        Consumption of clean energy -        Reduction of waste -        Use of fewer or cleaner consumables	-        Vergara Indicators
Optimisation of distribution systems	-        Disposal of packaging -        Smaller, cleaner and/or reusable packaging -        More energy-efficient modes of transport and logistics	-        Tomorrow Machine
Reduction of environmental impact during use	-        Low energy consumption -        Clean energy sources -        Reduction of consumables -        Clean consumables
Optimisation of product lifetime	-        High reliability and durability -        Ease of maintenance and repair -        Modular or adaptable product	-        ISSOP label
Optimisation of system end-of-life	-        Encourage the reuse of the complete product -        Remanufacturing or reconditioning -        Encourage recycling

However, the different positions adopted in the above-mentioned sectors are outlined below:

Firstly, edible or biodegradable packaging (1), followed by the reuse of food waste (2), continuing with the re-engineering of production processes (3) and ending with the reduction of plastic packaging (4).

Discussion

Continuing with the main objective of this review, the study of different design strategies to achieve Zero Waste products, different principles are observed throughout the conceptual and productive process in which companies and citizens can provide a boost in sustainable design.

There is a correlation between the collective thinking of society with respect to low environmental impact design and that the product is cleanly produced. In other words, companies do not invest in research and innovation to achieve sustainable products if this thinking is not a fundamental pillar of society.

In order to realise this boom in sustainable design and therefore sustainable consumption and use, it is necessary to invest in sustainable development both locally, nationally and internationally.

Continuous learning, training and analysis of the different techniques, research and recent innovations is necessary to ensure a complete development in the circular economy and to strip products of the sustainable limitations that have endured since the Industrial Revolution.

From the last third of the 20th century to the present day, progress has been made in the research of circular economy philosophies and/or models, which have raised both individual and collective awareness of the finite resources available and encouraged alternatives towards Zero Waste design.

Despite the different political or national confrontations in some countries over the years, an international programme has been implemented to promote and boost sustainable development, which establishes a series of objectives for the year 2030.

Currently, following the events of 2020, the COVID-19 pandemic, different sectors of design have been affected, especially the extraction of resources and raw materials, which have caused an international delay in the manufacture and distribution of components and products.

This situation can generate sustainable thinking towards a reintroduction of recycled materials and remanufactured components that reduce resource extraction and manufacturing time. Also, local distribution and local products benefit from this thinking, reducing the carbon footprint in the area of transport and logistics.

It is necessary to mention the importance of durable products and replace disposable products with reusable and/or biodegradable ones that do not increase both the ecological footprint and the carbon footprint.

From an economic or financial point of view, these products developed in a sustainable way towards a circular economy must be profitable, as mentioned above, this is achieved by changing the mentality of society, adding to the selection criteria in the choice of a product, its environmental impact, prioritising sustainable design.

Finally, the different demographics that make up the regions on a social and economic level must be taken into account, not allowing discrimination in the choice of product based on their economic or social status.

Conclusions

The lines of research of various authors coincide with the main fundamentals described in this review, suggesting in the same way, the existing problem with the future of the planet, for which a change in the global mentality of society is essential.

For decades, societies, companies and governments have tried to contribute to the modification of the global environmental state, obtaining as a result of these agreements, treaties and protocols, a long-term social and governmental initiative, but with little current positive repercussion.

By investing a small gesture in the production process, each company and/or government can boost the circular economy and promote sustainability according to the above-mentioned phases.

However, it is necessary to reason out the negative implications that this philosophy may have in terms of lifestyle, hygiene or the tools needed to carry it out.

Concluding with the World Design Organisation (WDO, 2020), "today more than ever our role is to transform social estrangement into cohesion" in which the circular economy represents a good starting point for research in the design sector today, experimenting towards a sustainable future through simple solutions.

References

Acciona (n.d.) This is what the fight against planned obsolescence looks like. Retrieved 16 March 2021, from https://www.sostenibilidad.com/desarrollo-sostenible/asi-lucha-contra-obsolescencia-programada/

Aranda, A. & Zabalza, I. (2010) Ecodesign and life cycle analysis. Prensas Universitarias de Zaragoza (1st ed.) Zaragoza, Spain.

Asencio, A. (2020) New design strategies to inspire sustainable living. Retrieved on March 16, 2021, from https://blogs.3ds.com/perspectives/new-design-strategies-to-inspire-sustainable-living/

Balboa, C. H., & Somonte, M. D. (2014). Circular economy as a framework for eco-design: the ECO-3 model. Technical Informer, 78(1), 82-90.

Banks, M. (2017) INNOVEIT 2017: Shaping the future of EU innovation. The Parliament. Retrieved on 16 March 2021, from https://www.theparliamentmagazine.eu/news/article/innoveit-2017-shaping-the-future-of-eu-innovation

Contreras, W., Owen, M.E., Cloquell, V., Cloquell, V.A. & Segundo, A. (2012) The coclowen sustainability wheel, a systemic and integrative reference to achieve environmentally friendly industrial products. University of Valencia, Valencia, Spain.

Daigneau, E. (2017) Two Environmental Buzzwords, Same Meaning? Zero waste" and "circular economy" are often used interchangeably. Retrieved on 2 March 2021, from https://www.governing.com/archive/gov-zero-waste-circular-economy.html

Ezpeleta Lascurain, I., Justel Lozano, D., Zubelzu Lacunza, J., Bereau Mutuberria, U., & Elizburu Oregi, A. (2019). Identification of key aspects of the circular economy for inclusion in life cycle design.

García, D. (2020) Analysis of the Zero Waste movement as a method for sustainable development and its possible application in the hotel sector on the island of Tenerife. University of La Laguna, Tenerife, Spain.

Giménez, E., Cabedo, L., FeijooJ.L., Fukushima, K. & Lagarón, J.M. (2008) Biodegradable polymeric nanocomposites: new materials for food packaging. I Iberoamerican Symposium on Waste Engineering. Castellón, Spain.

González Ordaz, Gilberto Israel, & Vargas-Hernández, José G.. (2017). The circular economy as a factor of social responsibility. Economía Coyuntural, 2(3), 105-130. Retrieved April 25, 2021, from http://www.scielo.org.bo/scielo.php?script=sci_arttext&pid=S2415-06222017000300004&lng=es&tlng=es

International Organization for Standardization (n.d.) ISO: About Us. Retrieved May 19, 2021, from https://www.iso.org/about-us.html

Instituto Tecnológico del Embalaje, Transporte y Logística (2018) Biodegradable materials for packaging: a sustainable alternative that ITENE delves into with SINSOST. Retrieved 23 May 2021, from https://www.itene.com/sala-de-prensa/notas-de-prensa/i/12627/60/materiales-biodegradables-para-envase-una-alternativa-sostenible-en-la-que-itene-profundiza-con-sinsost  

Madge, G. (2021) Atmospheric carbon dioxide to pass iconic threshold. Met Office. Retrieved on 2 March 2021, from https://www.metoffice.gov.uk/about-us/press-office/news/weather-and-climate/2021/2021-carbon-dioxide-forecast

Montes, L. (2017) A bubble to drink water without using bottles. El Mundo. Retrieved on March 16, 2021, from https://www.elmundo.es/economia/2017/10/24/59ef0de4e2704ecd798b4578.html

UNITED NATIONS PROGRAMME (n.d.) Sustainable Development Goals. Retrieved 25 April 2021, from https://www.undp.org/content/undp/es/home/sustainable-development-goals.html

Schneider, H. & Samaniego, J.L. (2009) The carbon footprint in the production, distribution and consumption of goods and services. United Nations publication. Santiago de Chile, Chile

Simon, J.M., McQuibban, J. & Condamine, P. (2020) Zero Waste Action Plan: Transforming the vision of the circular economy into a reality for Europe. Barcelona

Remix El Barrio (2021) "Remix El Barrio", design with biomaterials from food waste. MATERFAD. Retrieved on March 19, 2021, from https://www.fad.cat/materfad/es/agenda/6715/remix-el-barrio-disseny-amb-biomaterials-de-restes-alimentaries

Terradas, Jaume. (2016). Planetary boundaries. 10.13140/RG.2.1.4802.7925. 2009. Planetary boundaries. Ambienta, 89: 8-18.

Tomorrow Machine (n.d.) We believe in the future of packaging. Retrieved April 17, 2021, from https://www.tomorrowmachine.com/

Vergara, L.E. (2018) Model to assess and improve the fitness for sustainable development of a nation. University of Valencia, Valencia, Spain.

World Design Organization (2020). Designing towards a circular economy. Retrieved on April 19, 2021, from https://wdo.org/designing-towards-circular-economy/