[eng] Among the various materials that make up marine debris, lumps of petroleum waxes such as paraffin and microcrystalline wax, are regularly found on beaches worldwide, although not included in the current definition of marine litter. Ingestion by marine organisms is occasionally documented in the scientific literature and mass beaching events are frequently reported along the European coasts, with obvious detrimental consequences to the local communities that have to manage the clean-up and disposal of this substance. According to Annex II of the MARPOL regulation, petroleum waxes are classified as 'high viscosity, solidifying, and persistent floating products,' whose discharge at sea of tank-washing residues is strictly regulated, but currently permitted within certain limits. Starting from the description of a large stranding event occurred along the Italian coasts in 2017, we review the existing knowledge and regulatory framework and urge the relevant authorities to address this issue, showing that wax pollution is creating evident damages to the European coastal municipalities. Pending further investigations on the potential hazard that this kind of pollution is posing to marine ecosystems, we suggest a careful and more stringent revision of the policies regulating discharges of these products at sea.
Marine plastic debris floating on the ocean surface is a major environmental problem. However, its distribution in the ocean is poorly mapped, and most of the plastic waste estimated to have entered the ocean from land is unaccounted for. Better understanding of how plastic debris is transported from coastal and marine sources is crucial to quantify and close the global inventory of marine plastics, which in turn represents critical information for mitigation or policy strategies. At the same time, plastic is a unique tracer that provides an opportunity to learn more about the physics and dynamics of our ocean across multiple scales, from the Ekman convergence in basin-scale gyres to individual waves in the surfzone. In this review, we comprehensively discuss what is known about the different processes that govern the transport of floating marine plastic debris in both the open ocean and the coastal zones, based on the published literature and referring to insights from neighbouring fields such as oil spill dispersion, marine safety recovery, plankton connectivity, and others. We discuss how measurements of marine plastics (both in situ and in the laboratory), remote sensing, and numerical simulations can elucidate these processes and their interactions across spatio-temporal scales. ; The work of SCOR WG 153 is supported by national committees of the Scientific Committee on Oceanic Research (SCOR) and by Grant OCE-1546580 to SCOR from the US National Science Foundation. EvS, PD, MK, DW, DL and JA were supported through funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement 715386). EvS and PD were also partially supported by the European Space Agency (ESA) through the Sea surface KInematics Multiscale monitoring (SKIM) Mission Science (SciSoc) Study (contract 4000124734/18/NL/CT/gp). SA was funded through PNRA IPSODES. SPG was funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation)—Project Number 417276871. TvdB was supported by a Royal Academy of Engineering Research Fellowship. ICh and LKh were supported by the Russian Science Foundation, project number 19-17-00041. AB was supported by Russian Foundation for Basic Research grant 18-55-45024. AC was supported by the MIDaS project (CTM2016-77106-R, AEI/FEDER/UE). MPZ is supported through the PLASTICOUNT project, Toulouse INP-INSA-ISAE 2018. VMV was supported by the ESA General Studies Programme through the OPTIMAL grant (project No. 4000120879/17/NL/PS). The contributions of BFK were made possible by a grant from The Gulf of Mexico Research Initiative. TK acknowledges support from NSF Grant OCE-1352422. MAMM was partly funded by the UK Natural Environment Research Council award Combining Autonomous observations and Models for Predicting and Understanding Shelf seas (CAMPUS, NE/R006776/1). AI was supported by the Environmental Research and Technology Development Fund (SII-2) of the Ministry of the Environment, Japan. WJS was supported by the Ministry of Oceans and Fisheries, Korea, under the research project titled 'Environmental Risk Assessment of Microplastics in the Marine Environment'. BDH is supported by CSIRO Oceans and Atmosphere and Oak Family Foundation. ER was funded under NASA grant NNN13D462T. NM was partly supported by NASA Grants 80NSSC17K0559 and NNX17AH43G. No data collected by that initiative was used in this publication. This publication is Eprint ID 50829 of the Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung and contributes to the Pollution Observatory of the Helmholtz Association–funded program FRAM (Frontiers in Arctic Marine Research). We thank Anneke Vries for providing the first draft of figure 4. ; Peer Reviewed ; Postprint (published version)
