This guide outlines some of the most important information and stats related to plastic in the ocean (which is a separate issue to plastic on land).
We look at types of ocean plastic pollution, along with sources and causes, impact, and potential solutions.
Summary – Plastic In The Ocean
There’s many reasons the ocean is important to us as humans and as a society, so it makes sense to understand and address plastic in the ocean
Several estimates indicate that around 8 million tons of plastic go into the ocean per year
This amount of plastic could increase annually in the future as we produce and use more total plastic in society
Plastic that enters the ocean can usually be classified as coming from land based sources, or, marine based sources
Land based plastic makes up about 70 to 80% of plastic in the ocean in total, whilst marine based plastic makes up about 20 to 30%.
In specific parts of the ocean that are heavily fished or have heavy ocean traffic from sea vessels for example, marine based based make make up a higher % of plastic pollution in that area (up to around 50 or 60%)
One of the main types of land based plastic that enters the ocean is plastic packaging
One of the main types of marine based plastic that enters the ocean is ‘ghost gear’ from fishing that is dumped or lost to the sea (fishing lines, pots, fishing equipment and even sometimes whole boats are examples)
Plastic that enters the ocean from land based sources is usually a result of mismanaged plastic.
Mismanaged plastic includes plastic that is littered, and plastic that is disposed of inadequately (such as via open/unsecure landfills where it leaks into the environment)
Plastic enters the ocean mostly from coastal populations in close vicinity to the ocean (less than 50kms from the coastline)
Littered plastic can blow or wash into to ocean, or can runoff into it too
Other plastics can be carried into the ocean from inland locations via rivers and waterways
A high share of the world’s ocean plastics pollution has its origin in Asia.
China contributes the highest share of mismanaged plastic waste with around 28 percent of the global total
East Asia and the Pacific lead all regions at 60%
A large majority of rivers that carry plastic into the ocean are located in Asia (about 86%).
China is home to the River Yangtze – the top plastic polluting river by plastic input into the ocean in the world
Some of the main solutions for reducing ocean plastic pollution might involve cleaning up existing plastic in the ocean, reducing the rate of littering of plastic, reducing the rate of inadequately disposed of plastic, and introducing penalties or initiatives for marine plastic waste dumping and pollution.
We may also target specific regions and countries in the world who are most responsible for the highest rates of land and marine based ocean plastic pollution
How Much Plastic Goes Into The Ocean Every Minute?
… one garbage truck of plastic [packaging] goes into the ocean every minute
… If we carry on as usual, this is expected to increase to two per minute by 2030 and four per minute by 2050.
By 2050, this could mean there will be more plastic than fish in the world’s oceans
Medium.com outlines that each garbage truck has ‘the capacity to carry 15 tons when full’, but we must also consider the efficiency of garbage truck collection, in which, say for example, one ton of non compressed plastic might only be collected at a time.
How Much Plastic Goes Into The Ocean Each Year?
Estimates per year can vary, but most estimates put the amount of plastic input into the ocean at somewhere around 8 million tons a year.
Between 4.8 and 12.7 million tonnes of plastic enter the ocean each year
More than 8 million tons of plastic is dumped into our oceans every year
Annual estimates of ocean plastic input is in the order of up to 10 millions tonnes
How Much Plastic Is In The Ocean In Total, Right Now?
Exact estimates of total plastic in the ocean are hard to make.
The reasons for this are that it’s hard to say exactly what happens to all plastic once it goes into the ocean, and, it’s hard to find accurate methods to quantify the amount of plastic in the ocean right now.
But, some estimates are:
[it is estimated there are 150 million metric tons of plastic in the ocean right now, and] if we don’t do something now, we could be facing 250 million metric tons in the ocean in less than 10 years [because] plastic production and consumption are predicted to double over the next 10 years
… [in 2019] there are 5.25 trillion pieces of plastic floating on the sea surface. It all adds up to 269,000 tons. That is heavier than 11 Statues of Liberty. Many scientists think there is even more than that.
… The rest is underwater [as a result of plastic breaking down into smaller pieces of plastic, like microplastics, and sinking into deeper water]
Types Of Plastic Found In The Ocean (Land vs Marine Plastic)
Plastic found in the ocean can be categorised mainly as coming from a land origin (land based), or marine origin (marine based).
Most land based plastic comes from plastic packaging, and most marine based plastic is from fishing equipment and fishing gear.
Land based plastic overall makes up the majority of plastic found in the ocean globally, at around 70-80%, and marine at 20-30%.
But, different geographic regions of the ocean can contain different shares of each plastic type.
Areas of the ocean where fishing is more intensive can contain a higher share of marine based plastic.
One example is the Great Pacific Garbage Patch, where a 50% or greater share of plastic is marine based.
Land vs Marine Plastic
… it’s likely that marine sources contribute between 20-30 percent of ocean plastics, but the dominant source remains land-based input at 70-80 percent
Read more on this stat in the ‘Ocean plastic sources: land vs marine’ section at https://ourworldindata.org/plastic-pollution
Nearly half the plastic waste in the oceans is from packaging, but over half isn’t.
For example, approximately 640,000 tonnes of plastic enters the oceans each year as ‘ghost gear’ from boats and ships; fishing lines and nets lost or dumped overboard.
On plastic packaging:
A full 32% of the 78 million tons of plastic packaging produced annually is left to flow into our oceans
[marine plastic comes from] fishing fleets that leave behind [discarded fishing equipment like] fishing nets, lines/ropes, ropes, and sometimes abandoned vessels
How Does Plastic Get Into The Ocean?
In general, the cycle of plastic getting into the ocean is:
Plastic is produced
Plastic is used
Plastic becomes waste, and is disposed of
Some plastic is recycled, but the vast majority ends up in landfill. Some is also littered
Some landfills are well managed and most of the plastic stays in the landfill. But, some landfills are open or uncontained, and the plastic is lost or leaks from the land fill (known as inadequately disposed of plastic)
Mismanaged plastic (inadequately disposed plastic, and littered plastic) gets into the ocean via several routes, such as wind or tidal transport, but rivers also play a big part, as well as waste water and stormwater runoff
Marine based plastic can be dumped or discarded straight off of fishing vessels as well
Where Does Plastic In The Ocean Come From? (Sources Of Ocean Plastic Pollution)
As mentioned above, plastic in the ocean comes from land or marine based sources.
But, specifically, it comes mainly from:
Original Plastic Source
In terms of plastic waste by industry
The plastic packaging industry (ourworldindata.org)
In terms of total plastic waste by country
China produced the largest quantity of plastic, at nearly 60 million tonnes. This was followed by the United States at 38 million, Germany at 14.5 million and Brazil at 12 million tonnes (ourworldindata.org)
In terms of per capita plastic waste by country
Kuwait, Guyana, Germany, Netherlands, Ireland, the United States (ourworldindata.org)
In terms of inadequately disposed of plastic (one part of mismanaged plastic, which is material which is at high risk of entering the ocean)
High income countries have far lower rates of inadequately disposed plastic than middle and low income countries because of far more effective waste management [such as landfill sites that better contained and not open]. (ourworldindata.org)
In terms of littered plastic (the other part of mismanaged plastic)
[there is] a rate of littering of 2 percent of total plastic waste generation across all countries [and this plastic is at risk of ending up in the ocean] (ourworldindata.org)
In terms of total mismanaged plastic waste
Ahigh share of the world’s ocean plastics pollution has its origin in Asia. China contributes the highest share of mismanaged plastic waste with around 28 percent of the global total, followed by 10 percent in Indonesia, 6 percent for both the Philippines and Vietnam. See other countries at https://ourworldindata.org/plastic-pollution
In terms of mismanaged plastic waste by region
East Asia and the Pacific lead all regions at 60%
How & Where Plastic Gets Into The Ocean
In general – coastlines, rivers, tides, and marine sources are the entry points for plastic into the ocean
Two of the most important factors in plastic waste ending up in the ocean are – proximity of [a] given population centres to the coast, and national waste management strategies (ourworldindata.org)
[Coastal populations within 50km from the coast line are where most of the plastic is at risk of entering the ocean] (ourworldindata.org)
Aside from wind or tidal transport, waste water, and storm water, rivers play a key role in carrying plastic to coastal areas from inland areas.
The top 20 polluting rivers accounted for more than two-thirds (67 percent) of the global annual river input. Geographically we see that the majority of the top 20 rivers are located in Asia. The River Yangtze, the top polluting river, had an input of approximately 333,000 tonnes in 2015 —just over 4 percent of annual ocean plastic pollution. [the Ganges River in India and Bangladesh comes in second at 115,000 tonnes, and the Xi River in China third at 73,900 tonnes (ourworldindata.org)
[Asia by far leads plastic inputs to the ocean by region at 86%]
Fishing vessels play a key role in discarding or dumping plastic into the ocean from marine based sources
Other Sources Of Ocean Plastic
… plastic microfibres … are shed into wastewater when clothes made from materials such as nylon, acrylic or polyester are washed.
[some sources indicate] half a million tonnes of plastic microfibres a year are now ending up as pollution in the ocean – 16 times more than the plastic microbeads from cosmetics … [and it is claimed] over a third (35 per cent) of primary microplastics entering oceans are released through the washing of textiles, and microfibres are more likely than other types of microplastic to absorb toxic chemicals, which may be injurious to health.
How Much Plastic In The Ocean Is From Straws?
It’s estimated that if all straws around the world’s coastlines were lost to the ocean, this would account for approximately 0.03 percent of ocean plastics.
A global ban on their use could therefore achieve a maximum of a 0.03 percent reduction
So, some don’t see straws as a significant part of the ocean plastics problem when measured by quantity or %.
But, something we also have to consider is the negative impact straws have compared to other plastic on marine life for example – are they more or less damaging even though they are lesser in quantity or % than other plastic items?
How Much Plastic In The Ocean Is From Fishing?
In general, about 20 to 30% of plastic in the ocean is from fishing and marine based sources.
But, in certain regions of the ocean, like for example regions/areas where intensive fishing occurs, this % can be much higher.
One example is the Great Pacific Garbage Patch …
What Is The Island Of Plastic In The Ocean? (Great Pacific Garbage Patch, & Other Patches Of Waste)
Islands of plastic in the ocean are plastics that tend to migrate towards the centre of ocean basins.
One ‘island of plastic’ is the Great Pacific Garbage Patch – you can read more about it’s characteristics at https://ourworldindata.org/plastic-pollution
What Happens To Plastic In The Ocean?
There is a big discrepancy between the amount of plastic estimated to be entering ocean yearly, and the amount of plastic estimated to be floating on ocean surface water.
There are multiple hypothesis’ as to where the rest of the plastic ends up beneath the surface of the water – this is sometimes referred to as the ‘missing plastic’ problem.
Plastic is buoyant, so it tends to firstly collect on the surface of ocean waters (where it is transported by the prevalent wind and surface current routes, and accumulates in oceanic gyres, with high concentrations of plastics at the centre of ocean basins, and much less around the perimeters – ourworldindata.org)
In 2014, there was approximately 269,000 tonnes of plastic in surface waters [in the ocean] across the world (ourworldindata.org)
You can read more about the ocean basins that have the most plastic mass at https://ourworldindata.org/plastic-pollution
‘Missing Plastic’, & Below Surface Plastic
It’s unknown where the majority of ocean plastics end up
… within the marine environment, plastics can more readily break down into smaller particles [for a variety of reasons]
A likely ‘sink’ for ocean plastics are deep-sea sediments … The other possible sinks of missing plastics are shallow-sea sediments, in addition to potential ingestion by organisms. The quantification of these aspects are as yet unknown.
… new research may suggest a third explanation: that plastics in the ocean break down slower than previously thought, and that much of the missing plastic is washed up or buried in our shorelines
… [it is also possible] due to imprecise measurement: we might either grossly overestimate the amount of plastic waste we release into the ocean, or underestimate the amount floating in the surface ocean
[surface plastic] slowly breaks down. As it breaks apart, tiny pieces fall into deeper water. These pieces are called microplastics. Many are so small they can’t be seen without a microscope. Water currents carry them all across the planet.
[it’s estimated] some four billion plastic microfibers per square kilometer litter the deep sea
Effects Of Plastic In The Ocean
Two of the main potential effects of plastic in the ocean are on wildlife, and on humans.
We summarise and link to further resources both below.
Impact Of Plastic In The Ocean (How Plastic Affects Marine Life & Animals)
The full impact of plastic on wildlife and ecosystems is not yet know.
But, the three main ways it is known right now that plastic impact wildlife is by:
and, Interaction and Abrasion
Along with those three ways, micro plastic specifically can accumulate in the marine environment can impact wildlife via ingestion.
Read more about each of these at https://ourworldindata.org/plastic-pollution
… plastic impacts nearly 700 species from our ocean
Plastic has been found in more than 60% of all seabirds and in 100% of sea turtles species, that mistake plastic for food.
And when animals ingest plastic, it can cause life-threatening problems, including reduced fitness, nutrient uptake and feeding efficiency
Read more about how plastic impacts marine animals in this guide.
Impact Of Plastic In The Ocean On Humans & Human Health
It is thought micro plastics in particular may potential for impact on humans and human health, but:
There is, currently, very little evidence of the impact of microplastics in humans. Despite having no clear evidence of health impacts, research on potential exposure is ongoing (ourworldindata.org)
The plastic particles themselves, the release of persistent organic pollutant absorbed to the plastics, and leaching of plastic additives are three areas of concern.
Read more at https://ourworldindata.org/plastic-pollution
Solutions To Plastic In The Ocean – How To Stop & Reduce It, & How To Clean It Up
We’ve put together a couple of guides looking at potential solutions:
But, in general, we might reduce or stop plastic pollution by:
1. Cleaning up and removing plastic already in the ocean
Micro plastics and plastic beneath the ocean surface are difficult to remove.
But, there are several projects and initiatives trying to clean up and remove ocean surface plastic – investors and researchers from The Ocean Cleanup are a main example.
Read more about cleaning up plastic and what is done with it once removed from the ocean at https://www.weforum.org/agenda/2016/10/every-minute-one-garbage-truck-of-plastic-is-dumped-into-our-oceans/
2. Preventing plastic from entering the ocean in the first place
This could involve a range of things such as… reducing the rate of plastic waste, reducing the rate of plastic littering, reducing the rate of inadequately disposed of plastic (one way to do this is by investing in plastic disposal systems that don’t allow plastic to leak into the environment as easily), and introducing penalties or initiatives to reduce the amount of marine plastic pollution from sea vessels and fishing boats
3. Target countries and regions most responsible for plastic pollution into ocean
Lower income countries who can’t afford adequate plastic disposal systems and facilities, and particularly Asia as a region, may be two places to start
Ocean vs Beach Plastic Waste
There is a difference between plastic waste found on the beach, and waste that ends up in the ocean water.
Here are two guides that summarise waste and plastic waste found on beaches:
4. Hannah Ritchie and Max Roser (2019) – “Plastic Pollution”. Published online at OurWorldInData.org. Retrieved from: ‘https://ourworldindata.org/plastic-pollution’ [Online Resource]