Plastic marine pollution is a global environmental challenge. Research on marine plastic debris dates back to the 1970s, with most efforts focusing on floating plastics and microplastics collected during oceangoing expeditions. These studies mapped global surface plastic distribution, identifying subtropical gyres as accumulation zones. In contrast, subsurface plastic research has lagged but has recently advanced through regional observations. Microplastics have been found throughout the water column, from coastal zones to the open ocean, spanning equatorial to polar seas, and in marine organisms at different trophic levels. Despite these advances, methods for quantifying small plastics (microplastics and nanoplastics) remain inconsistent at every stage, complicating intercomparisons. These discrepancies hinder efforts to leverage empirical data for understanding plastic sources, transport pathways, sinks, and long-term ecological impacts.
This working group aims to address challenges in data collection, quality control in both field and laboratory settings, and the harmonization of plastic pollution datasets in the water column while strengthening international collaboration and national research capacity. This effort will produce a best-practices report detailing sample collection, measurement techniques, and quality control protocols, with recommendations on reference materials, to improve quantifications of small plastics budget and flux. The group will also assess the validation status and reliability of existing datasets, propose unified standards for data and metadata publication, and promote data deposition in open-access repositories. Furthermore, interlaboratory comparisons will be undertaken to ensure methodological alignment, and targeted capacity building efforts will support research development in underrepresented regions, addressing current disparities in access to advanced measurement techniques.
The working groups selected at the 2025 SCOR annual meeting are still taking feedback from the reviews under consideration, which may result in additions to the membership and other small revisions.
- Chair(s)
- Shiye Zhao (Japan), Luisa Galgani (italy), Karin Kvale (New Zealand)
- Other Full Members
- Giuseppe Suaria (Italy), Roswati Md Amin (Malaysia), Sara Purca (Peru), Clara Manno (UK), Martin Löder (Germany), Lixin Zhu (China-Beijing), Ryan Bos (USA)
- Associate Members
- Martin Thiel (USA), Anela Choy (USA), Helge Niemann (Netherlands), Seung-Kyu Kim (South Korea), Tristan Naidoo (South Africa), Mufti Petala Patria (Indonesia)
- Reporter
- Hilkka Ndjaula
- Terms of Reference
Develop best practices for subsurface small plastic measurements. Assess current and emerging methods for measuring subsurface plastic concentrations, vertical fluxes, and ingestion by water-column organisms, identify and evaluate the advantages/disadvantages of these methods, and recommend specific approaches to ensure methodological consistency across studies.
Enhance data quality and accessibility. Review quality control/assurance (QC/QA) protocols in existing studies to assess the validation and qualification status of reported data, and determine their accessibility. Recommend best-practices for QC/QA and propose unified standards for data and metadata distribution to facilitate effective quality control between producers and scientific users. Promote data sharing through open-access platforms to support intercomparison and benchmark assessments.
Strengthen methodological consistency. Conduct interlaboratory exercises by subdividing large volumes of particle samples into subsamples with consistent internal standard, distributing them across laboratories using different measurement techniques. Compare analytical outcomes across laboratories to identify methodological biases and enhance reproducibility.
Leverage archived samples to address data gaps. Review methodologies from international scientific projects and evaluate the potential for using archived marine particle and biological samples collected by international research programs for retrospective plastic quantification. Provide protocols, guidelines and recommendations for their effective reuse.
Disseminate findings and build capacity. Share the Working Group outcomes through international conferences, open-access publications, and global/regional networks. Actively promote capacity building through workshops and exchange visits to standardize methodologies for producing and reporting high-quality data.
- Approved
- October 2025
- Financial Sponsors
- SCOR, NSF