Floating oceanic debris tends to accumulate at the center of gyres and on coastlines, frequently washing aground, when it is known as beach litter or tidewrack.
[3] Dumping, container spillages, litter washed into storm drains and waterways and wind-blown landfill waste all contribute to this problem.
[7] A wide variety of man-made objects can become marine debris; plastic bags, balloons, buoys, rope, medical waste, glass and plastic bottles, cigarette stubs, cigarette lighters, beverage cans, polystyrene, lost fishing line and nets, and various wastes from cruise ships and oil rigs are among the items commonly found to have washed ashore.
[9] Millions of pounds of ordnance were disposed of in the Gulf of Mexico and off the coasts of at least 16 states, from New Jersey to Hawaii (although these, of course, do not wash up onshore, and the U.S. is not the only country who has practiced this).
[12] In a 2014 study using computer models, scientists from the group 5 Gyres, estimated 5.25 trillion pieces of plastic weighing 269,000 tons were dispersed in oceans in similar amount in the Northern and Southern Hemispheres.
Indigestible material may accumulate in the gut creating blockages or a false sense of fullness and eventually death from lack of appropriate nutrient intake.
They can entangle fish, dolphins, sea turtles, sharks, dugongs, crocodiles, seabirds, crabs, and other creatures, including the occasional human diver.
[16] Acting as designed, the nets restrict movement, causing starvation, laceration and infection, and suffocation in those that need to return to the surface to breathe.
When these products are used, the microplastics go through the water filtration system and into the ocean, but because of their small size they are likely to escape capture by the preliminary treatment screens on wastewater plants.
The microplastics are such a concern because it is difficult to clean them up due to their size, so humans can try to avoid using these harmful plastics by purchasing products that use environmentally safe exfoliates.
Research thus far has shown that debris in the deep-ocean is in fact impacted by anthropogenic activities, and plastic has been frequently observed in the deep-sea, especially in areas off-shore of heavily populated regions, such as the Mediterranean.
[24] Litter, made from diverse materials that are lighter than surface water (such as glasses, metals and some plastics), have been found to spread over the floor of seas and open oceans, where it can become entangled in corals and interfere with other sea-floor life, or even become buried under sediment, making clean-up extremely difficult, especially due to the wide area of its dispersal compared to shipwrecks.
Other oceanic processes that affect circulation, such as coastal storms and offshore convection, play a part in transferring large volumes of particles and debris.
[24] The 10 largest emitters of oceanic plastic pollution worldwide are, from the most to the least, China, Indonesia, Philippines, Vietnam, Sri Lanka, Thailand, Egypt, Malaysia, Nigeria, and Bangladesh,[27] largely through the rivers Yangtze, Indus, Yellow, Hai, Nile, Ganges, Pearl, Amur, Niger, and the Mekong, and accounting for "90 percent of all the plastic that reaches the world's oceans.
[31] In 2007, MSC Napoli beached in the English Channel, dropping hundreds of containers, most of which washed up on the Jurassic Coast, a World Heritage Site.
[33] A 1997 accident of Tokio Express ship off the British coast resulted in loss of cargo container holding 5 million Lego pieces.
[34] In Halifax Harbour, Nova Scotia, 52% of items were generated by recreational use of an urban park, 14% from sewage disposal and only 7% from shipping and fishing activities.
[39][40] On the remote sub-Antarctic island of South Georgia, fishing-related debris, approximately 80% plastics, are responsible for the entanglement of large numbers of Antarctic fur seals.
Iron and concrete structures typically do little damage to the environment because they generally sink to the bottom and become immobile, and at shallow depths they can even provide scaffolding for artificial reefs.
[43] Additionally, hermit crabs have been known to use pieces of beach litter as a shell when they cannot find an actual seashell of the size they need.
[46] Bulky plastic debris may become permanently lodged in the digestive tracts of these animals, blocking the passage of food and causing death through starvation or infection.
[47] Tiny floating plastic particles also resemble zooplankton, which can lead filter feeders to consume them and cause them to enter the ocean food chain.
In addition, plastic in the marine environment that contaminates the food chain can have repercussions on the viability of fish and shellfish species.
The Corps has been doing this work since 1942, when a seaplane carrying Admiral Chester W. Nimitz collided with a piece of floating debris and sank, costing the life of its pilot.
[55] Once a year there is a diving marine debris removal operation in Scapa Flow in Orkney, run by Ghost Fishing UK, funded by World Animal Protection and Fat Face Foundation.
[56][57][58] Cleanup of marine debris can be stymied by inadequate collaboration across levels of government, and a patchwork of regulatory authorities (responsibility often differs for the ocean surface, the seabed, and the shore).
[67][68] In June 2019, Ocean Voyages Institute, conducted a cleanup utilizing GPS trackers and existing maritime equipment in the North Pacific Subtropical Convergence Zone setting the record for the largest mid-ocean cleanup accomplished in the North Pacific Gyre and removed over 84,000 pounds of polymer nets and consumer plastic trash from the ocean.
[88] In the waters of the United States, there have been many observed consequences of pollution including: hypoxic zones, harmful agal blooms, and threatened species.
On 11 April 2013 in order to create awareness, artist Maria Cristina Finucci founded the Garbage Patch State at UNESCO –Paris in front of Director General Irina Bokova.
Though ocean and coastal area cleanups are important, it is crucial to address plastic waste that originates from inland and landlocked states.