Legal efforts have been made at the international and national levels to address marine pollution. However, compliance with these laws is still poor, partly due to limited financial resources to enforce them.
Existing international legally binding instruments should be further explored to address plastic pollution. Recycling and reuse of plastic materials are the most effective actions available to reduce the environmental impacts of open landfills and open-air burning that are often practiced to manage domestic waste.
Sufficient litter and recycling bins can be placed in cities, and on beaches in coastal areas to accelerate the prevention and reduction of plastic pollution. Governments, research institutions and industries also need to work collaboratively redesigning products, and rethink their usage and disposal, in order to reduce microplastics waste from pellets, synthetic textiles and tyres. This will require solutions which go beyond waste management, to consider the whole lifecycle of plastic products, from product design to infrastructure and household use.
To effectively address the issue of marine plastics, research and innovation should be supported. Knowledge of the full extent of plastic pollution and its impacts would provide policy-makers, manufacturers and consumers with scientific evidence needed to spearhead appropriate technological, behavioural and policy solutions.
It would also accelerate the conceptualisation of new technology, materials or products to replace plastics. Issues Briefs related to nature conservation and sustainable development often have societal impacts beyond conservation. Thevenon, F. Boucher, J.
What is the issue? Of course, better marine litter prevention and ocean conservancy begins with a better understanding of the root causes of ocean pollution. What Causes Marine Litter?
Explore Causes of Marine Debris. Share Tweet. What Is Marine Litter? The Impact of Marine Debris Marine litter is not only ugly — it can harm ocean ecosystems, wildlife, and humans.
Types of Marine Debris and Litter There are many types of marine litter. Plastics are one of the most extensive types of marine debris. They are commonly used in many items, and as society has developed new uses for them the variety and quantity of plastic items found in the marine environment has increased dramatically. Plastics are now known to break down into smaller components, called microplastics. Microplastics and their associated toxic chemical components contribute to human and wildlife health risks as the toxic microplastics are ingested and move through the marine food web.
Research in discovered that plastic particle counts reached one million plastic particle parts per square mile in Lake Erie, with higher counts found in Lake Ontario; 1 The Great Lakes have among the highest densities of microplastics recorded. Microfibers, a type of microplastic, are also pervasive in the marine environment, and while our knowledge of the impacts of microfibers is limited, they make up the majority of microplastics, and can even be found in the seafood we consume.
Plastics such as bottle caps, balloons, and lighters are mistaken for food or the debris item may have been attached and ingested accidentally with other food by wildlife such as sea turtles, seabirds, and marine mammals. Plastic ingestion leads to loss of nutrition, internal injury, intestinal blockage, starvation, and death in wildlife.
Seabirds are especially vulnerable to plastic pollution; a recent study found plastic in 90 percent of seabirds. A second highly visible and impactful form of marine debris is derelict fishing gear DFG. DFG has numerous impacts on the environment, including: damaging marine habitats, entangling marine species including seabirds and marine mammals, creating hazards to navigation, and ghost fishing of commercially important species resulting in lost catch opportunities and economic losses for fishermen.
One of the most notable types of impacts from this type of marine debris is wildlife entanglement. Derelict nets, ropes, line, or other fishing gear can wrap around marine life. Entanglement has led to injury, illness, suffocation, starvation, and death.
Sea turtles are at great risk for entanglement in marine debris, and this has caused injuries and in many cases death for a variety of sea turtle species.
One study found that between —, over 1, sea turtles were found stranded in Florida due to entanglement in fishing gear. These areas are often heavily fished, resulting in snagging of hooks and discarding of lines. Bird species become entangled when swimming in bodies of water where line and netting is carelessly discarded, and sometimes use fishing line and netting fragments as nesting material, which can lead to entanglement of both the parents and chicks.
Easy solutions for responsible fishers include proper disposal of monofilament line and awareness of safe procedures for dehooking and disentangling entrapped birds. ADVs threaten oceans, coasts, and waterways by obstructing navigational channels, causing harm to the environment, and diminishing commercial and recreational activities.
ADVs may pose an immediate or future threat to wildlife and wildlife habitat from the release of hazardous substances to surrounding areas. ADVs may occur in large numbers, following a natural disaster such as a hurricane, or as a single vessel. Following the hurricanes, the Service and its partners removed damaged vessels from Florida, Puerto Rico, U.
Virgin Islands National Wildlife Refuges and adjacent communities. ADVs occurring in remote locations are difficult to reach for cleanup and assessment of the impacts. Removal of such ADVs is very expensive and technical. Although the sum of the wreck was removed initially by the responsible party, over tons of debris were left behind on the perimeter of the reef and lagoon when funds ran out. Second, plastic litter can represent a relevant source of chemical additives, some of them with suspected endocrine disrupting action, that easily leach into the water since they are not bound to the polymeric chains and become available to the estuarine and marine fauna Hermabessiere et al.
Third, intentionally or accidentally discarded fishing gears pose special risks for large, air-breathing marine animals, including endangered species, which get entangled in the nets Lusher et al. Conventional plastics are non-biodegradable and they may persist in the environment for hundreds of years but also because of hydrodynamics and exposure to light, they may fragment into small particles readily taken up by marine organisms. Microplastics and nanoplastics are of particular concern: ingested by even the smallest zooplankton species they can transfer hydrophobic pollutants and plastic additives into the trophic webs, although thermodynamic models and experimental data provide conflicting results and more research is needed in this field Beiras et al.
Finally, plastic at sea may transport alien species over long distances or act as substratum for vagile and epistratum benthos, providing a support to colonization Casabianca et al. This Research Topic includes, as yet, 13 papers covering broad oceanic aspects of litter: development of methods, distribution in different species and marine areas, ingestion of plastic, toxicity of plastic associated chemicals, and policies dedicated to reduction measures of marine litter.
The impacts related to marine litter have been evaluated from ecological, ecotoxicological, economic and social perspectives, identifying four major subtopics for the papers featured:.
Sources of marine litter and environmental distribution and sinks: surveys in water, sediments, coast and biota. Experimental approaches. Impacts on marine organisms: macro-, meio-, and micro-fauna related to plastics and plastics' associated contaminants. In this Research Topic, studies considering sources and distributions of marine litter subtopic 1 span over awide geographic area and different environmental compartments, presenting results from surveys in water, beaches, sediments and biota.
Interactions between species and litter were reviewed for the South East Pacific, indicating the importance of entanglement, microplastic ingestion and the higher sensitivity of sea turtles to marine litter Thiel et al. In the North Atlantic, a much higher occurrence of microplastic fragments than previously reported was found in the gut contents of mesopelagic fishes Wieczorek et al. Regional surveys suggest that land-based inputs of plastics are to be reconducted to different levels of coastal anthropogenic pressure and population growth.
In an urban estuary in Tasmania, the type, distribution and abundance of microplastics observed closely matched data on increasing plastic production, coastal population growth, and proximity to urban water outflows Willis et al.
Methods were also addressed subtopic 2 with a review on constraints and priorities for conducting experimental exposures of marine wildlife to microplastics Paul-Pont et al.
Impacts of marine litter and marine plastics can be varied and concurrent, arising from entanglement, ingestion, and leaching of plastic-associated contaminants and additives subtopic 3. In marine fauna, negative effects of marine litter are documented on over 1, species and depend on a multiplicity of co-factors that need to be considered when developing management plans for the conservation of ecosystems and biodiversity Fossi et al.
Five studies describe the release of chemicals and their ecotoxicological effects on marine biota subtopic 3 , including two bivalve species O'Donovan et al. Clearly, action modes and toxicological pathways, also considering transcriptional activity, differ according to pollutants. In one freshwater species, significant adverse effects of leachates from expanded polystyrene were detected Thaysen et al. In terms of management subtopic 4 , the role of regulation, public perception and social license to operate in managing waste that enters the ocean were discussed Vince and Hardesty.
More specific case studies on paraffins were also reviewed in the framework of environmental policies, suggesting for regulatory measures Suaria et al. Overall, this Research Topic provides a panel of various aspects of the impacts of marine litter and plastics, and will largely support more research toward a better understanding of any harm caused by any material at all levels of biological organization.
Several gaps still need to be covered, from the harmonization of methodological approaches to study marine litter in different environmental compartments i.
Moreover, the impact of marine litter and, in particular, microplastics and nanoplastics, on human health is still largely debated and a more focused research needs to be carried out to properly address this issue. Models on plastic distribution and transfer in all marine compartments are needed to provide reliable estimates of marine fluxes from land to sea.
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