Since one animal eats another, microplastics can move through the food chain. The main question is what happens to the toxins and chemicals that are associated with these plastics. When plastic ends up in the environment, it tends to bind with environmental pollutants. With plastic that moves through the food chain, the attached toxins can also move and accumulate in animal fat and tissue through a process called bio-accumulation.
In addition, chemicals are often added to plastic during the production process, to give them some desired properties. These chemicals can in turn leak from the plastic, even when that plastic is inside the body of an animal. Plastic is by no means the only way that toxins, such as PCBs and dioxins, end up in the food chain.
Animals that excrete swallowed plastic may actually cleanse their bodies because toxins present in the body have attached themselves to the plastic. It is a different story for plastic additives. Unlike PCBs and dioxins, these substances have not accumulated in the food chain over the decades.
When Japanese researchers found a particular flame retardant in the tissues of seabirds, it was certain that it came from swallowed plastic to which the flame retardant was once added. The number of individual animals affected by plastic would be very difficult to estimate but would run into the billions.
Attempts have been made to determine the number of species affected. In , Dutch researchers found that the number of marine species that swallow or get caught in plastic had doubled since from to This number is now above , with the caveat that only a very limited number of animal species have been investigated.
Floating plastic debris are currently the most abundant items of marine litter. Plastic has been detected on shorelines of all the continents, with more plastic materials found near popular tourist destinations and densely populated areas. The main sources of marine plastic are land-based, from urban and storm runoff, sewer overflows, beach visitors, inadequate waste disposal and management, industrial activities, construction and illegal dumping. Ocean-based plastic originates mainly from the fishing industry, nautical activities and aquaculture.
Under the influence of solar UV radiation, wind, currents and other natural factors, plastic fragments into small particles, termed microplastics particles smaller than 5 mm or nanoplastics particles smaller than nm. Plastic pollution is the most widespread problem affecting the marine environment. It also threatens ocean health, food safety and quality, human health, coastal tourism, and contributes to climate change.
Impacts on marine environment The most visible and disturbing impacts of marine plastics are the ingestion, suffocation and entanglement of hundreds of marine species. Marine wildlife such as seabirds, whales, fishes and turtles, mistake plastic waste for prey, and most die of starvation as their stomachs are filled with plastic debris. They also suffer from lacerations, infections, reduced ability to swim, and internal injuries.
Floating plastics also contribute to the spread of invasive marine organisms and bacteria, which disrupt ecosystems. Toxic contaminants also accumulate on the surface of plastic materials as a result of prolonged exposure to seawater. When marine organisms ingest plastic debris, these contaminants enter their digestive systems, and overtime accumulate in the food web. The transfer of contaminants between marine species and humans through consumption of seafood has been identified as a health hazard, but has not yet been adequately researched.
Much of the macroplastics in our shorelines is from the past 15 years, but still a significant amount is older suggesting it can persist for several decades without breaking down.
In offshore environments, older microplastics have had longer to accumulate than in coastal regions. There macroplastics from several decades ago — even as far back as the s and s — persist. Most microplastics three-quarters in offshore environments are from the s and earlier, suggesting it can take several decades for plastics to break down.
How much plastic will remain in surface oceans in the coming decades? This also matters for how we solve the problem of ocean pollution. Click to open interactive version. Wordpress Edit Page. Our World in Data is free and accessible for everyone. Help us do this work by making a donation. The best guess, made in , was about million metric tons. Assuming things remain the same, the study estimates that accumulation will become million metric tons by Even a five-year delay allows an additional 80 million metric tons of trash to slide offshore.
White papers come and go. What sets the Pew report apart is that it arrives at a critical moment in the campaign to rein in plastic waste. In just five short years, ocean plastic pollution rocketed to the top tier of global environmental causes, setting in motion myriad campaigns in nearly every nation on Earth to scale back the use of disposable plastics.
Meanwhile, on another track, global plastic production is on pace to increase 40 percent by , and hundreds of billions of dollars are being invested in new plastic production plants, locking in the status quo, according to the report.
As plastic flows into the seas and more plastic is made, it also has become increasingly clear that environmental campaigns are not making enough progress. To the world, this will be the first eye-opening that our current efforts alone will not be enough. The global trajectory is going in the wrong direction.
Clearly, we need a fundamental rethinking of our relationship with this material. Find out why. We were data-poor. To fill in the picture, the team used a first-of-its-kind economic model, created by the University of Oxford in the U. An online version of the model went live today, allowing governments and businesses to plug in waste data and evaluate trade-offs and solutions tailored to local conditions. The team eventually numbered more than a hundred experts, and included collaborations with the University of Leeds, the Ellen MacArthur Foundation, and Common Seas, all in the U.
The model analyzes costs and measures plastic leakage into the sea when various scenarios, involving plastic use are employed.
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