The great pacific garbage patch
By: Lara zakaria, hannah shewan, sarah ohio-ohezmo, anisha vasireddy, celine markintonis
Great Pacific Garbage patch is a gyre (system of circulating ocean currents) which consists of marine debris particles. Located in the North of the Pacific Ocean, and consisting of plastic manly coming from Asia and from the Yangtze river, it is estimated that the Great Pacific Garbage Patch is between the Size of Texas (700,000 sq km) and the size of Russia (15,000,000 sq km)
impacts of the great pacific GARBAGE PATCH
Overall ecosystem health is gravely affected by the accumulation of trash. Marine debris ingestion and entanglement directly impacts marine life. Additionally, the mere presence of marine debris can disrupt an entire food web through its indirect impacts. Imagine that the entire biosphere is one large food web comprised of interrelated food chains. The disruption of tropic levels within a food chain can have effects on the entire food web.
The ratio of plastic to zooplankton in the major ocean gyres, which tend to concentrate floating material, is estimated to be up to 6:1 by weight. Whales, fish and other marine species depend on zooplankton for food, as they are the fundamental link to the phytoplankton who the capture sun’s energy.
Researchers currently believe plastics are taken up by zooplankton, thus entering the food chain. Plastics also bring toxins into the food chain. When plastics break down, they produce toxic products. They also aggregate pollutants in the environment. Both are released when animals digest the plastic.
While many of these species are threatened, still others form part of our diet. This means that plastic ingested by wildlife not only affect them - their guts may be perforated and they may starve - but toxins from the plastics may also be absorbed by humans.
Globally more than 200 species are known to be affected by marine rubbish including whales, seals, dugong, seabirds, turtles, crabs, sea snakes, sharks, rays and other fish.
Studies show that “ingested marine debris is quite common in samples of dead and captured seabirds and turtles”, indicating that many marine organisms mistake small bits of plastic and trash for food.
Ingestion of marine debris causes various effects in marine life, including “reducing the absorption of nutrients in the gut, reducing the amount of space for food in the gizzard and stomach, uptake of toxic substances that comprise the debris or have been absorbed into the debris, ulceration of tissues, and mechanical blockages of digestive processes.”
Entanglement is also a significant threat to marine species. For example, up to 40,000 fur seals are killed each year when they get tangled in debris. This contributes to a population decline of 4-6% per year.
Entanglement affects nearly all groups of marine vertebrates. We know that in Australian waters turtles, cetaceans, seals, sea lions, seabirds, sharks and rays, crabs and other animals are affected. Derelict fishing gear is particularly harmful as it often results in “ghost fishing”. This occurs when lost or abandoned fishing gear continues to catch fish that then goes to waste. Debris entanglement can also have damaging effects on marine habitats, such as coral reefs and sea grass destruction resulting from contact with derelict fishing gear. By 2050 there could be as much plastic as fish in the ocean, plastic can prevent ocean absorbing CO2 from the atmosphere which in turn exacerbates climate change.
HUMAN HEALTH IMPACTS
Plastic does not decompose. After coming into contact with the sun, plastic products continue to break into smaller and smaller pieces called “micro-plastics.”
Pre-production plastics, or “nurdles,” are small plastic pellets that are later melted and moulded to produce everyday plastic products. Massive quantities of nurdles often spill off ships and into the sea.
Scientists are concerned that plastics, particularly micro-plastics and nurdles, “are able to adsorb, concentrate, and deliver toxic compounds to organisms that ingest them or to benthic communities. In fact, studies have demonstrated that plastics readily absorb contaminants with greater ease than natural sediments like rocks and sand. The contaminants that plastics absorb include polychlorinated biphenyls (PCBs) and dichlorodiphenyltrichloroethane (DDT).
DDT and PCBs are persistent organic pollutants (POPs) that “can accumulate and pass from one species to the next through the food chain.” POPs have been linked with “reproductive, developmental, behavioural, neurologic, endocrine, and immunologic adverse health effects” in humans. Because micro-plastics and nurdles are easily ingested by species at the bottom of the food chain, humans are in danger of ingesting large quantities of POPs when consuming larger species, like tuna and wahoo.
As fisheries contribute greater than 20 percent of the average per capita animal protein intake for more than 1.5 billion people, these bioaccumulation effects are significant. Particularly at risk are the populations of small island states and developing nations who derive 90% of their animal protein from fish. POPs can also affect the next generation because they are transferred to developing offspring through the placenta and breast milk.
While the consumption of marine species may result in serious indirect impacts on human health, marine debris that washes ashore may also immediately and directly injure beachgoers. Debris such as glass and aluminium may cut people walking on the beach. More threatening, however, is the possibility of hazardous medical waste, like needles, washing ashore and injuring the public.
Marine debris has serious negative consequences on beach tourism and real estate property values.
A study of New Jersey estimated the state lost billions of dollars in tourism revenue as a result of marine debris washing ashore. A similar study demonstrated that New York forwent anywhere from $950 million to $2 billion. This decline in economic revenue stems from tourists foregoing ventures to the beach because of its distasteful appearance. For instance, a South African study concluded that 10 pieces of marine debris per meter of beach would deter 40 percent of foreign tourists.
Like tourism, housing values also suffer from the distasteful appearance and stench of trash floating nearby waterfront homes and cluttering the streets and alleys of neighbourhoods. As a prime beach tourism destination and real estate hub, south Florida must take measures to limit the amount of marine debris washing upon our beaches and reefs by investing in both public education to reduce single-use plastic consumption and in cleanups.
CHEMICAL EFFECTS ON BIODIVERSITY
Plastics both leach and absorb dangerous pollutants and toxic chemicals, including additives used in manufacturing. When plastics are broken down through photodegradation, which is the process by which light breaks down complex molecules into simpler products through oxidation, they leach out these colorants and chemicals which cause environmental and health problems. For example, bisphenol A, also known as BPA, affects the growth, reproduction, and development of aquatic organisms and is an endocrine (hormone) disruptor in humans. This means that it which interferes with the production, secretion, transport, action, function and elimination of natural hormones.
Plastics also absorb pollutants such as PCBs. These can be consumed by marine animals and concentrate and persist in the fatty tissue of living organisms when they are ingested, and therefore bioaccumulate up food webs, which has a wide-ranging impact on many different species.
The impact of toxic chemicals leaching into water can also affect the behaviour of aquatic animals who rely on chemicals to understand the world around them, from smaller animals such as periwinkles to larger animals such as crabs and fish. For example, periwinkles usually protect themselves from predators by withdrawing into their shells when they sense crab chemicals in the water. However, a study by the French National Centre for Scientific Research have shown that after periwinkles were placed in water containing plastic pellets, they no longer responded to those chemical cues. Being robbed of the ability to sense danger could leave animals more vulnerable to predation in the wild, which can affect entire food webs by increasing populations of predators etc.
In evaluation of the negating impacts of the Pacific Ocean Garbage Patch, we have come to the conclusion that the effects on the environment are of the greatest concern. This is due to the fact that the issues of pollution on the environment transcend into the food chain causing harm to humans as well. Furthermore, the economic impacts of the pollution are only a result of the harm that is being inflicted on the environment. Therefore more effort should be exerted to deal with the environmental impacts, which coincides with the ecocentric viewpoint.