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Biodegradability of Plastics in the Open Environment

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Biodegradability of Plastics in the Open Environment Science Advice for Policy by European Academies BIODEGRADABILITY OF PLASTICS IN THE OPEN ENVIRONMENT Evidence Review Report No. 8 Biodegradability of plastics in the open environment Informs the Scientifc Opinion of the European Commission’s Group of Chief Scientifc Advisors About the cover artwork By conducting our daily activities blinded by routine, we forget to take a moment to look and see what is surrounding us. Freathy, taken from a collagraph series titled Re(f)use, has been created using littered plastics, packaging and fshing net collected from its titled location. It captures the natural beauty that we as consumers may overlook or take for granted. The work’s purpose is to challenge the destructive behaviours of our society on the environment and initiate positive and efective steps towards ecological sustainability. About the artist Heather Nunn studied BA (Hons) Fine Art at Plymouth University in the UK, where she discovered a love for printmaking. Through her work, she expressed her passion for the environment whilst challenging the imbalances between modern society and nature, comparing the beauty to the ugliness of our existence. She spent her time at Plymouth University working alongside the Sustainable Earth institute and was awarded the Sustainability Prize 2016 for her works Re(f)use and (Ex)change. Instagram: @heather.ln Facebook: Heather Nunn Printmaker This Evidence Review Report has been produced under the auspices of the SAPEA consortium, as a deliverable under Grant Agreement 737432 “Science Advice for Policy by European Academies” that was signed by the consortium and the European Commission on 22 November 2016. The text of this work is licensed under the terms of the Creative Commons Attribution licence which permits unrestricted use, provided the original author and source are credited. The licence is available at http://creativecommons.org/licenses/by/4.0. Images reproduced from other publications are not covered by this licence and remain the property of their respective owners, whose licence terms may be diferent. Every efort has been made to secure permission for reproduction of copyright material. The usage of images reproduced from other publications has not been reviewed by the copyright owners prior to release, and therefore those owners are not responsible for any errors, omissions or inaccuracies, or for any consequences arising from the use or misuse of this document. In accordance with Article 35, paragraph 1 of the aforementioned Grant Agreement, the consortium identifed all relevant interests of the experts requested to contribute to this Evidence Review Report, assessed whether an interest constituted a confict of interests, and took — where relevant — measures to exclude that an interest could compromise or be reasonably perceived as compromising the impartiality or objectivity of the report. Further information about SAPEA’s quality guidelines and working processes is available at www.sapea.info. The information, facts and opinions set out in this report are those of the authors and do not necessarily refect the opinion of the European Commission. The SAPEA Consortium is not responsible for the use which may be made of the information contained in this report by anyone, including the European Union institutions and bodies or any person acting on their behalf. ISBN – 978-3-9820301-8-0 DOI 10.26356/biodegradabilityplastics Downloadable from www.sapea.info/topics/biodegradability-of-plastics SAPEA, Science Advice for Policy by European Academies. (2020). Biodegradability of plastics in the open environment. Berlin: SAPEA. doi:10.26356/biodegradabilityplastics Version history Version Date Summary of changes 1.0 14 December 2020 First published version 1.1 18 December 2020 Fixed typos; fxed referencing errors; updated table of contents 1.2 25 May 2021 Corrected typos in section 1.2: “tonnes” to “million tonnes” PUBLISHER CONTACT SAPEA SAPEA Communications Ofce c/o acatech Rue d’Egmont 13 Pariser Platz 4a Brussels 1000 | Belgium 10117 Berlin | Germany [email protected] About SAPEA SAPEA (Science Advice for Policy by European Academies) brings together outstanding expertise in engineering, humanities, medicine, natural and social sciences from over 100 academies, young academies and learned societies across Europe. SAPEA is part of the European Commission’s Scientifc Advice Mechanism. Together with the Group of Chief Scientifc Advisors, we provide independent scientifc advice to European Commissioners to support their decision-making. We also work to strengthen connections between Europe’s academies and Academy Networks, and to stimulate debate in Europe about the role of evidence in policymaking. The Evidence Review Report informs the Scientifc Opinion of the Group of Chief Scientifc Advisors. Funded through the EU’s Horizon 2020 programme, the SAPEA consortium comprises fve Academy Networks: Academia Europaea (AE), All European Academies (ALLEA), the European Academies’ Science Advisory Council (EASAC), the European Council of Academies of Applied Sciences, Technologies and Engineering (Euro-CASE), and the Federation of European Academies of Medicine (FEAM). For further information about SAPEA, visit www.sapea.info. 3 Table of Contents 3 ABOUT SAPEA 9 FOREWORD 10 EXECUTIVE SUMMARY 17 CHAPTER !: INTRODUCTION 17 1.1. Background to the development of plastics 17 1.2. Production of plastics, biodegradable plastics, and waste 20 1.3. Background to biodegradable plastics 21 1.4. The position of biodegradable plastics in waste management systems 22 1.5. EU policy landscape 24 1.6. Policy question 27 CHAPTER ": SETTING THE SCENE 27 2.1 Introduction 28 2.2 Defnitions of plastics and polymers 34 2.3 Defnition of ‘plastic biodegradation’ 38 2.4 Defnition of ‘open environment’ 40 2.5 Steps involved in plastic biodegradation 44 2.6 Factors controlling plastic biodegradation in the open environment 58 CHAPTER #: APPLICATIONS OF BIODEGRADABLE PLASTICS: CONSIDERATIONS RELATING TO ENVIRONMENTS 58 3.1. Applications of plastic products in relation to the waste hierarchy — where do biodegradables ft? 61 3.2. The infuence of the receiving environments on the benefts of biodegradable plastics 65 3.3. Examples of applications in which the use of biodegradable plastics may bring beneft 70 3.4. Applications where benefts are less clear 71 3.5. The importance of labelling and appropriate user information 72 3.6. The importance of legislation and enforcement 75 CHAPTER $: TESTING, STANDARDS AND CERTIFICATIONS 75 4.1 Introduction 78 4.2 Testing scheme and requirements 89 4.3 Criteria for the selection of tests and modelling 91 4.4 Standardisation 102 4.5 Certifcation 106 4.6 Communication and labelling 107 4.7 Existing gaps 108 4.8 Options and challenges for policy 111 4.9 Conceptual fowchart for the assessment of biodegradation of a plastic item in the open environment: three scenarios 4 Table of Contents 119 CHAPTER %: ECOLOGICAL RISK ASSESSMENT 119 5.1 Introduction and Chapter outline 120 5.2 Risk assessment 123 5.3 Ecotoxicology 124 5.4 Plastics in the environment and related risks 129 5.5 Potential risks of biodegradable plastics in the environment 137 5.6 Risk assessment of biodegradable plastics, problem formulation (Phase 1) 149 CHAPTER &: SOCIAL, BEHAVIOURAL AND POLICY ASPECTS 149 6.1 Introduction 152 6.2 Public understanding, perceptions and behaviour 154 6.2.2 Consumer perceptions of sustainable and biodegradable packaging 160 6.3 Unintended consequences of biodegradable plastics 168 6.5 Evidence-based policy options and regulation 174 6.6 What is not known 178 CHAPTER ': CONCLUSIONS AND POLICY OPTIONS 178 7.1. Conclusions 179 7.2. Evidence-based policy options 185 REFERENCES 211 ANNEX !: LIST OF WORKING GROUP MEMBERS 212 ANNEX ": ACKNOWLEDGEMENTS 214 ANNEX #: BACKGROUND TO THE REPORT 216 ANNEX $: POLICY LANDSCAPE AND OTHER INITIATIVES RELATING TO BIODEGRADABLE PLASTICS 221 ANNEX %: GLOSSARY 5 6 Foreword Plastics pollution of the world’s open environments — our oceans, rivers and land — is a global challenge that has come to the forefront of public awareness in recent years. The issue has been raised in previous reports from the European Commission’s Scientifc Advice Mechanism, Food from the Oceans, A Scientifc Perspective on Microplastics in Nature and Society, and Environmental and Health Risks of Microplastic Pollution. It is against this backdrop that the Group of Chief Scientifc Advisors agreed to address the question of whether applications of biodegradable plastics have a role to play in the implementation of the European Commission’s strategy on plastics, set within the context of the circular economy and the waste hierarchy. The work is extremely timely and will help to inform the development of European policy and legislation in this crucial area. SAPEA was delighted to be asked to undertake this comprehensive evidence review, which informs the Scientifc Opinion of the Advisors. It is the eighth Evidence Review Report to be published by the SAPEA consortium, an integral part of the European Commission’s Scientifc Advice Mechanism. SAPEA assembled an outstanding working group of European experts from a variety of disciplines, backgrounds and countries. It is this unique interdisciplinary approach that we believe makes the report such a landmark contribution to the feld. The project has been overseen by Academia Europaea, acting as the Lead Academy on behalf of SAPEA. Due to the COVID pandemic, this has been the frst review to be conducted entirely by virtual means, rather than through
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