Sources, Fate and Effects of plastics and micro-plastics in the marine environment

Lead agency: Intergovernmental Oceanographic Commission (UNESCO-IOC) and United Nations Environment Programme (UNEP)

Background

It is widely recognised that marine litter can have significant ecological, social and economic impacts. Plastics form a large proportion of marine litter, and the widespread occurrence of macroscopic plastic debris and the direct impact this can have both on marine fauna and legitimate uses of the environment, sometimes remote from industrial or urban sources, has been well documented. Plastic debris comes in a wide variety of sizes and compositions and has been found throughout the world ocean, carried by ocean currents and biological vectors (e.g. stomach contents of fish, mammals and birds). Plastics degrade extremely slowly in the open ocean, partly due to UV absorption by seawater and relatively low temperatures. In recent years the existence of micro-plastics and their potential impact has received increasing attention. The extent of the impact of plastic litter in the oceans is uncertain, despite the considerable scientific effort that has been expended in recent years.

Current Focus of WG40, third phase: 2017 - to present

WG40 was initiated in 2012, as a consequence of the GESAMP Emerging Issues programme. Details of its development, aims and outcomes are summarised in the History of WG40 section below. Following discussion at the 43rd GESAMP Session in 2016, the Terms of Reference for a third phase of WG 40 were agreed. The remit of WG 40 has been expanded to include methods related to both macro-plastic and micro-plastic litter. This is reflected in the new title of the working group.

Phase 3 Terms of Reference:

  1. To develop guidelines covering terminology and methodologies for the sampling and analysis of marine macro-plastics and microplastics, including:

i) size and shape definitions of particles;

ii) sampling protocols for the whole spectrum of particle/object sizes in surface and sub-surface seawater, seabed sediments, shorelines and biota;

iii) methodologies for physical and chemical identification and analysis of polymers and associated chemicals;

iv) requirements for monitoring and assessment.

2. To assess the occurrence and effects of nano-sized plastics on marine organisms, and make research and policy-relevant recommendations.

3. To assess the significance of plastics and microplastics as a vector for indigenous and non-indigenous organisms, and make research and policy-relevant recommendations.

The focus in 2017–2018 is to develop guidelines covering terminology and methodologies for the sampling and analysis of marine macro-plastics and microplastics, more specifically: the size and shape definitions of particles; sampling protocols for the whole spectrum of particle/object sizes in surface and sub-surface seawater, seabed sediments, shorelines and biota; and, methodologies for physical and chemical identification and analysis of polymers and associated chemicals requirements for monitoring and assessment. It is considered essential to collaborate with a wide range of Regional Seas and other regional organisations, to ensure the guidelines are relevant for those organisations with responsibility for undertaking monitoring and assessment for plastics and microplastics. It is intended to publish the guidelines before the end of 2018.

The membership of the working group has been refreshed, to reflect the new objectives. The total membership is 15, with representatives from 14 countries in Africa, North and South America, Asia, Australasia and Europe. Two additional co-chairs have been appointed to cover the macro-plastic (Alexander Turra, Brazil) and microplastic (Francois Galgani, France) methods and protocols.

Additional financial and in-kind support to cover the 1st ToR has been agreed with: IMO; FAO; NOAA, USA (Marine Debris Program); Ministry of Environment, Japan (G7 Marine Litter Action Plan); State Ocean Administration, China (G20 Marine Litter Action Plan); the North West Pacific Action Plan (NOWPAP) (G7 – Regional Seas collaboration); and, the BASEMAN – JPI Oceans project (microplastics methods).

The first meeting of WG40 in phase three took place in Paris in September. Further meetings of the working group are being planned during the 6th International Marine Debris Conference (6IMDC) to be held in San Diego, United States, in March 2018, with a second full workshop planned for June 2018.

History of WG40:

The question of the degree to which micro-plastics and associated chemical loads present a risk to organisms was raised through the GESAMP emerging issues programme. Following the preparation of a scoping paper in 2009, a Workshop was held in June 2010, hosted by UNESCO-IOC in Paris, bringing together experts from industry, academia, NGOs and policy making to examine plastic particles as a vector in transporting persistent, bio-accumulating and toxic substances in the oceans. The proceedings of this Workshop were subsequently published as GESAMP Reports and Studies No. 82 in 2010.

One of the recommendations was that GESAMP should create a new working group: ‘Sources, fate and effects of miroplastics in the marine environment - a global assessment.’ WG40 was formed in 2012, with IOC as the lead agency and with additional in-kind or financial support from IMO, UN Environment Programme, the NOAA, Plastics Europe and the American Chemistry Council.

First Phase: 2012 - 2014

The initial Terms of Reference:

  1. Assess inputs of micro-plastic particles (e.g. resin pellets, abrasives, personal care products) and macro-plastics (including main polymer types) into the ocean; to include pathways, developing methodologies, using monitoring data, identifying proxies (e.g. population centres, shipping routes, tourism revenues);
  2. Assess modelling of surface transport, distribution and areas of accumulation of plastic and micro-plastics, over a range of space- and time-scales;
  3. Assess processes (Physical, chemical and biological) controlling behaviour and the rate of production of ‘secondary’ micro-plastic fragments;
  4. Assess long-term modelling including fragmentation, seabed and water column distribution, informed by the results of ToR 3;
  5. Assess uptake of particles and their contaminant/additive load by biota, as well as their physical and biological impacts at a population level; and
  6. Assess the social and economic aspects including public awareness.

WG40 workshops took place in Paris, London and Busan, in the Republic of Korea, attended by 16 members from 12 countries in North and South America, Africa, Asia and Europe.

Members of WG40 at the third workshop in Busan, July 2014: a) searching for micro-plastics on shoreline near Busan; b) touring the analytical facilities at the KIOST laboratory under the direction of Dr Won Joon Shim.

The first global assessment report was published in 2015 in the GESAMP Reports and Studies Series

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In addition, a summary of the main conclusions and recommendations was published for policy makers and the lay readership.

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The assessment made a number of recommendations for further investigation, which the group concluded was required to cover certain topics in greater depth or introduce new elements into the assessment. This led to the initiation of the second phase.

Second Phase: 2015 – 2016

A revised work programme was agreed for the second phase:

  1. to carry out a comprehensive assessment of the topic with input from a wide range of disciplines over a 3-4 year timeline;


  2. to provide input to the 2nd United Nations Environment Assembly (May 2016) on topics of particular interest to UN Environment and FAO.

Part (b) was initiated at the request of UN Environment, to contribute to a broader effort on the impact of plastics and marine plastics in the marine environment, in response to a Resolution passed at the inaugural United Nations Environment Assembly, which took place in Nairobi in 2014. The Resolution (1/6 Paragraph 14) required the Executive Director of UN Environment to carry out a study on ‘Marine plastic debris and microplastics’:

‘…… building on existing work and taking into account the most up-to-date studies and data, focusing on:

(a) Identification of the key sources of marine plastic debris and microplastics;

(b) Identification of possible measures and best available techniques and environmental practices to prevent the accumulation and minimize the level of microplastics in the marine environment;

(c) Recommendations for the most urgent actions;

(d) Specification of areas especially in need of more research, including key impacts on the environment and on human health;

(e) Any other relevant priority areas identified in the assessment of the Joint Group of Experts on the Scientific Aspects of Marine Environmental Protection;’

GESAMP was requested to carry out the microplastics aspects of the study with IOC-UNESCO and UN Environment sharing the lead agency role. The Terms of Reference of WG40 were revised and the membership of WG40 was refreshed and expanded accordingly, with generous financial support from the Government of Norway, administered by UN Environment.

Phase 2 Terms of Reference:

  1. Assess the main sources and categories of plastics and microplastics entering the ocean. 


  2. Assess and utilize a range of physical and chemical models to simulate the behaviour of plastics and microplastics in the ocean in order to improve current assessment technologies.

  3. Assess the occurrence and effects of microplastics in commercial fish and shellfish species, including associated additive chemicals and contaminants in the edible fractions. 


  4. Assess local, regional and global scales of accumulation of plastics and associated chemicals (additives and absorbed contaminants), including SIDS and regional hotspots. 


  5. Assess the effects of nano-sized plastics on marine organisms 


  6. Assess the risk of physical and chemical effects of ingested microplastics on 
marine organisms. 


  7. Assess the significance of plastics and microplastics as a vector for organisms, 
facilitating the spread of non-indigenous (alien) species. 


  8. Develop guidelines covering terminology and methodologies: i) size and shape 
definitions of particles; ii) sampling protocols for the whole spectrum of particle sizes in surface and sub-surface seawater, seabed sediments, shorelines and biota; 
and, iii) methodologies for physical and chemical identification and analysis of polymers and associated chemicals.

  9. Assess social and economic aspects influencing both the entry of 
plastics/microplastics into the ocean and the potential consequences from the 
resulting contamination. 


  10. Develop and utilize effective mechanisms for communicating the progress and 
conclusions of the working group to a wide audience (public and private sector). 


WG40 workshops were held in Rome, Paris and Guayaquil (Ecuador), with contributions at various times from 25 invited experts representing 18 countries from North and South America, Africa, Asia, Australasia and Europe. Representatives from FAO, IOC and UN Environment took part, and ACC and Plastics Europe attended as Observers.

Members of WG40 Phase 2, enjoying the sunshine on the rooftop at FAO in Rome, April 2015.

The results of Phase 2 were published in 2016 in the GESAMO Reports and Studies Series, and represented a significant contribution to the Marine plastics and microplastics study, presented at UNEA-2 in May 2016 in Nairobi.

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