93 SOURCES, FATE AND EFFECTS OF MICROPLASTICS IN THE MARINE ENVIRONMENT: PART 2 OF A GLOBAL ASSESSMENT Science for Sustainable Oceans ISSN 1020–4873 REPORTS AND STUDIES AND STUDIES REPORTS AND REPORTS 93 SOURCES, FATE AND EFFECTS OF MICROPLASTICS IN THE MARINE ENVIRONMENT: PART TWO OF A GLOBAL ASSESSMENT A report to inform the Second United Nations Environment Assembly GESAMP Working Group 40 2nd phase REPORTS AND STUDIES REPORTS Published by the INTERNATIONAL MARITIME ORGANIZATION 4 Albert Embankment, London SE1 7SR www.imo.org Printed by Micropress Printers Ltd. ISSN: 1020-4873 Cover photo: Peter Kershaw Notes: GESAMP is an advisory body consisting of specialized experts nominated by the Sponsoring Agencies (IMO, FAO, UNESCO-IOC, UNIDO, WMO, IAEA, UN, UNEP, UNDP). Its principal task is to provide scientific advice concerning the prevention, reduction and control of the degradation of the marine environment to the Sponsoring Agencies. The report contains views expressed or endorsed by members of GESAMP who act in their individual capacities; their views may not necessarily correspond with those of the Sponsoring Agencies. Permission may be granted by any of the Sponsoring Agencies for the report to be wholly or partially reproduced in publication by any individual who is not a staff member of a Sponsoring Agency of GESAMP, provided that the source of the extract and the condition mentioned above are indicated. Information about GESAMP and its reports and studies can be found at: http://gesamp.org ISSN 1020-4873 (GESAMP Reports & Studies Series) Copyright © IMO, FAO, UNESCO-IOC, UNIDO, WMO, IAEA, UN, UNEP, UNDP 2015 For bibliographic purposes this document should be cited as: GESAMP (2016). “Sources, fate and effects of microplastics in the marine environment: part two of a global assessment” (Kershaw, P.J., and Rochman, C.M., eds). (IMO/FAO/UNESCO-IOC/UNIDO/WMO/IAEA/UN/ UNEP/UNDP Joint Group of Experts on the Scientific Aspects of Marine Environmental Protection). Rep. Stud. GESAMP No. 93, 220 p. Report editors: Peter J. Kershaw and Chelsea M. Rochman Contributors to the report: Linda Amaral-Zettler, Anthony Andrady, Sarah Dudas (Chapter 5 lead), Joan Fabres, Francois Galgani (Chapter 7 lead), Denise Hardesty (Chapter 3 lead), Valeria Hidalgo-Ruz, Sunny Hong, Peter Kershaw, Laurent Lebreton (Chapter 2 lead), Amy Lusher, Ramani Narayan, Sabine Pahl, James Potemra, Chelsea Rochman, Sheck A. Sherif, Joni Seager, Won Joon Shim, Paula Sobral, Shige Takada, Patrick ten Brink (Chapter 6 lead), Martin Thiel, Richard Thompson, Alexander Turra, Lisbeth Van Cauwenberghe, Erik van Sebille, Dick Vethaak (Chapter 4 lead), Emma Watkins, Kayleigh Wyles, Chris Wilcox, Erik Zettler and Patrizia Ziveri. GLOSSARY Organizations, techniques and other terms Short form Full name ALDFG Abandoned, Lost and otherwise Discarded Fishing Gear FAO Food and Agriculture Organization FT-IR Fourier transform infrared spectroscopy UNEA United Nations Environment Assembly Common polymers Short form Full name Short form Full name ABS Acrylonitrile butadiene styrene PGA Poly(glycolic acid) AC Acrylic PLA Poly(lactide) EP Epoxy resin (thermoset) PP Polypropylene PA Polyamide 4,6, 11, 66 PS Polystyrene PCL Polycaprolactone EPS (PSE) Expanded polystyrene PE Polyethylene PU (PUR) Polyurethane PE-LD Polyethylene low density PVA Polyvinyl alcohol PE-LLD Polyethylene linear low density PVC Polyvinyl chloride PE-HD Polyethylene high density PU (PUR) Polyurethane PET Polyethylene terephthalate SBR Styrene-butadiene rubber Common chemical additives in plastics Short form Full name Examples of function BPA Bisphenol A a monomer used in the manufacture of polycarbonates and epoxy resins DBP dibutyl phthalate anti-cracking agents in nail varnish DEP diethyl phthalate skin softeners, colour and fragrance fixers DEHP di-(2-ethylhexyl)phthalate plasticizer in PVC HBCD hexabromocyclododecane flame retardant NP nonylphenol stabilizer in food packaging and PVC PBDEs Polybrominated diphenyl ethers flame retardants (penta, octa & deca forms) nonylphenol stabilizer in PP, PS phthalates Phthalate esters improve flexibility and durability Common organic contaminants absorbed by plastics Short form Full name Origin DDT dichlorodiphenyltrichloroethane insecticide PAHs Polycyclic aromatic hydrocarbons combustion products PCBs polychlorinated biphenyls cooling and insulating fluids, e.g. in transformers GESAMP REPORTS & STUDIES No. 93 – MICROPLASTICS IN THE OCEAN · 3 Contents Page EXECUTIVE SUMMARY ......................................................................... 11 ACKNOWLEDGEMENTS ........................................................................ 13 1 INTRODUCTION ..................................................................... 15 1.1 Context ......................................................................... 15 1.2 GESAMP WG40 work programme and timeline .......................................... 15 1.3 Structure and scope of the report ..................................................... 16 2 SOURCES OF MICROPLASTICS ...................................................... 17 2.1 Lessons from the first assessment .................................................... 17 2.2 Primary and secondary sources of microplastics ........................................ 17 2.2.1 Overview of microplastic sources ............................................. 17 2.2.2 Fragmentation and degradation .............................................. 18 2.3 Sources by sector ................................................................. 20 2.3.1 Sources in brief ........................................................... 20 2.3.2 Producers and converters ................................................... 20 2.3.3 Land-based sectoral consumers. 21 2.3.4 Sea-based sectoral consumers ............................................... 22 2.3.5 Individual consumers ....................................................... 25 2.3.6 Waste management ........................................................ 25 2.4 Entry points to the ocean ........................................................... 26 2.4.1 Rivers ................................................................... 26 2.4.2 Coastline ................................................................ 30 2.4.3 Marine ................................................................... 31 2.4.4 Atmosphere .............................................................. 32 2.5 Scale variability ................................................................... 32 2.5.1 Time-scale-dependency .................................................... 32 2.5.2 Regional scale dependency .................................................. 33 2.6 Conclusions, knowledge gaps and priorities ............................................ 34 2.6.1 Conclusions .............................................................. 34 2.6.2 Knowledge gaps .......................................................... 34 2.6.3 Research priorities ......................................................... 34 3 DISTRIBUTION, FATE AND ‘HOT-SPOTS’ .............................................. 36 3.1 Lessons from the first assessment .................................................... 36 3.2 Microplastics in ocean compartments ................................................. 36 3.2.1 Compartments in brief ...................................................... 36 3.2.2 Microplastics on the ocean surface. 36 3.2.3 Microplastics in the water column ............................................. 37 3.2.4 Microplastics on the seafloor ................................................. 37 3.2.5 Shoreline/Coastal regions ................................................... 39 3.2.6 Biota .................................................................... 39 3.3 Transport within compartments ...................................................... 39 3.3.1 Upper ocean .............................................................. 39 3.3.2 Water column ............................................................. 40 GESAMP REPORTS & STUDIES No. 93 – MICROPLASTICS IN THE OCEAN · 5 3.3.3 Deep ocean .............................................................. 40 3.3.4 Coastlines ................................................................ 40 3.3.5 Biota .................................................................... 41 3.4 Fluxes between compartments ....................................................... 41 3.5 ‘Hot-spots’ and scale-dependency .................................................... 42 3.6 Conclusions, knowledge gaps and research priorities ..................................... 43 3.6.1 Conclusions .............................................................. 43 3.6.2 Knowledge gaps .......................................................... 43 3.6.3 Research priorities ......................................................... 43 4 ECOLOGICAL IMPACTS OF MICROPLASTICS ......................................... 44 4.1 Lessons from the first assessment .................................................... 44 4.2 Occurrence of microplastics in biota .................................................. 44 4.2.1 Microplastics in the marine environment ........................................ 44 4.2.2 Exposure pathways and concentrations of microplastics in marine organisms ......... 45 4.2.3 Laboratory studies ......................................................... 45 4.2.4 Field studies .............................................................. 49 4.3 Impacts