Final report
Dates and location
6 May — 8 May 2024, Lerici, Italy
Chairperson
Claudia Cenedese
Co-chairperson
Bruce Sutherland and Giuseppe Suaria
Conference fees
- Early-bird registration: 220.00 €
- Late registration (in Dollars $): 260.00 €
What other funding was obtained?
None
What were the participants offered?
Digital book of abstracts.
Two daily coffee breaks and three lunches.
One dinner and one mixer.
Applicants (members)
- Luca Brandt
- Claudia Cenedese
- Marco De Paoli
- Rama Govindarajan
- Tobias Kukulka
- Adrien Lefauve
- Eckart Meiburg
- Federico Pizzi
- Hugo Poncelet
- Alfredo Soldati
- Bruce Sutherland
- Gautier Verhille
- Andy Woods
Applicants (non members)
- Francois Blanchette
- Meike Bos
- Daniel Carlson
- Sara Cloux
- Michael Denes
- Michelle Dibenedetto
- Jennifer Dingwall
- Qiang Dotzel
- Michael Dotzel
- Melinda Hall
- Chisa Higuchi
- Matthew Hoffman
- Atsuhiko Isobe
- Quentin Kriaa
- Mao Kuroda
- Zhixuan Liu
- Jessamy Mol
- Andrea Paluselli
- Vicente Perez-Munuzuri
- Samantha Phan
- Marie Poulain-Zarcos
- Larry Pratt
- Nimish Pujara
- Luz Andrea Silva Torres
- Giuseppe Suaria
- Laura Sunberg
Scientific report
Altogether there were 39 participants and 31 presentations. The full program is available in a separate document. Most importantly, there was ample time for informal discussions among the participants during coffee breaks, lunches and social activities.
During and following many stimulating and diverse talks, attendees discussed the next steps going forward. The problem of predicting the pathways from sources to sinks in rivers and the ocean is vast. Rama Govindarajan suggested a framework be developed to help our community synthesize ideas and provide focus for our research endeavors.
Some suggestions for a framework include developing zeroth order equations, akin to ecological modelling that has lots of parameters. Another idea was to develop box models that estimate fluxes of plastics from various sources (municipal waste, ocean dumping, etc.) to various reservoirs (rivers, coastal regions, open ocean, etc.) to various sinks (beaches, river sediments, abyssal floor, etc.). Some box models have previously been developed, but with less emphasis on plastic dispersion pathways. Aspirationally, as a zeroth order summary one would like to develop a box model that specifies the mass flux (Mton/year) of plastic released into various marine reservoirs from various sources, subdividing these into what fraction are buoyant and negatively buoyant and which are macroplastics and microplastics (shape could be a further consideration).
For each of these, the model also would specify the mass flux corresponding to the transformation of particles from buoyant to negatively buoyant, from macroplastic to microplastic, and transport from one type of reservoir to another (e.g. from coastal to open ocean). Finally, the model would specify the mass flux from various reservoirs to sinks.
Although some studies have already attempted to estimate mass (if not, volume) fluxes in a narrow range of the above cases, great uncertainty exists even in those cases: is there even missing plastic?
After the final discussion, it was generally felt that developing a box model providing numbers for mass fluxes would be overambitious at this time. Keeping in mind our original goal to help provide focus to our diverse collection of research endeavors, a suggestion put forward by Michael Denes following the discussion was to create a living document in which members of our community could upload and download references to published work related to various transport pathways.
The document could also include links to observational databases (e.g. the Atlas of Ocean Microplastics) and modelling resources (e.g. PlasticParcel). To this end, we have created a GoogleDoc that can be accessed by anyone with the following link
This document contains links to observational and modelling resources as well as references to published articles related to microplastic dispersion pathways. References are grouped as they relate to pathways from various sources to various marine reservoirs to various sinks, as well as transformation pathways from macroplastics to microplastics and from buoyant to negatively buoyant particles. Processes within various marine reservoirs can also be included. As a crude guide, net sources, reservoirs, and net sinks are subclassified as follows:
● Net sources
Municipal waste
Storm drains
Runoff
Dumping from land
Dumping at sea
Atmosphere (net source of plastics, but also a partial sink)
● Reservoirs
Rivers and estuaries
Swash zone
Near coast
Western boundary currents
Open ocean - near surface
Open ocean - thermocline
Open ocean - abyss
● Sinks
River and estuary beds
Beaches
Near shore sediments
Continental margins
Abyssal floor
Number of participants from each country
| Country | Participants |
|---|---|
| United States | 12 |
| Netherlands | 4 |
| United Kingdom | 4 |
| Japan | 4 |
| France | 4 |
| Italy | 3 |
| Spain | 3 |
| Austria | 2 |
| Germany | 1 |
| India | 1 |
| Canada | 1 |
| Total | 39 |