Sailing in an ocean of plastic. Facts about plastic waste in the seas.

Sailing in an ocean of plastic. Facts about plastic waste in the seas.

The ocean for us sailors, is the most beautiful of elements. But in just a matter of years, will our boats be accompanied by plastic bottles instead of adorable dolphins?

Virgin nature, crystal-clear sea and a rich marine life - these are the greatest attractions that truly capture our heart. The ocean is the most beautiful element for us sailors. But in just a matter of years, will our boats be accompanied by plastic bottles instead of adorable dolphins?


The problem, of course, is not just about us sailors. The oceans and seas cover more than 70% of our planet. They supply half our oxygen and absorb up to one third of the carbon dioxide.


They are home to millions of animals and a source of livelihood for countless people. Almost 2.4 billion people live within 100 kilometers of the coast.


In the future, will our planet still be blue or just full of plastic?

Car tyres dumped on coral reef in seaCar tyres dumped on coral reef in sea 

Is plastic really a problem?

Each year, more than 8 million tons of plastic reach the ocean. According to a study published in March 2015 in the magazine Science, this number may be higher - up to 14 million tons per year. This is equivalent to dumping a full truck of plastic into the sea every minute. To put a specific figure to the total, imagine over 200 billion plastic bottles per year.

Every single year, plastic waste kills a million seabirds, 100,000 marine mammals, sea turtles and untold numbers of fish. Plastics remain in the ecosystem for countless years and are harming marine animals every day.

Plastics account for up to 80% of all waste in the seas. According to some estimates, at the rate plastic products are being discarded, by 2050 there will be more plastic in the sea than fish and an estimated 99 percent of seabirds will have fragments of plastic in their bowels.

How plastic waste reaches the sea

  • 80% of all sea pollution is as a result of land-based activities. Asia accounts for more than 63% of the plastics discarded - more than a quarter produced by China and to a large extent by Indonesia, the Philippines, Thailand and Vietnam. The US is the highest ranking developed country in the 2015 ranking in 20th place.
  • According to a German study, more than 90% of the plastics that end up in the sea are brought there by ten large rivers flowing through densely populated areas. Eight of them are in Asia and two more (the Nile and Niger) in Africa.3 The problem, albeit much smaller, is also from Europe. The Danube alone annually collects and then releases approximately 1,700 tons of plastic into the sea.
  • Plastic waste, however, can also get into the sea during a natural disaster. A study, published in the journal Scientific Reports, estimates that the 2011 earthquake in Japan swept plastic waste into the sea which made up 20 percent of the total.

Garbage and wastes on the beachGarbage and wastes on the beach 

How much plastic is actually floating in the ocean?

Since the invention of plastic, over 8 billion tons of it have have been produced worldwide. At present, around 300 million tons of plastic is produced annually, 40% of which is packaging (the forecast for 2020 is 400 million tons). However, recycling systems cannot keep up with this expansion in demand and the problem is compounded by the current cut in recycling by China.


Estimates suggest that only 9% of plastic is recycled, another 12% burned, and the remaining 79% of plastic waste pollutes the environment. If the current trend continues, the Earth will have generated around 34 billion tons of plastic by 2050.4


Determining exactly how much plastic waste is floating in the oceans is not easy and not even exactly possible. One frequently cited study 20135 estimated the total amount of plastic in the sea to be only 269,000 tons.  


Oceanographer Marcus Erikson, along with a group of scientists, had carried out 24 expeditions in 2007 and 2013. They collected data on key water streams and the amount and size of plastics. However, they only focused on plastics that float on the surface.


As a result, this number is far from accurate as it wasn’t possible to include waste that no longer floats. Such waste is even more dangerous. We now also know that every year there are 8 million more tons of plastics. Where does all this plastic disappear to?

Where plastic waste accumulates

A total of 57% of plastic waste is floating in the northern hemisphere. And most of it is in the northern Pacific. There lies the so-called Great Pacific garbage patch. But it isn’t the only one.


There are six similar artificial islands floating in the world’s oceans. But mapping and chronicling them is almost impossible. Due to ocean currents their shape, size, density and even location are constantly changing.


Similar patches of waste can also be found in the Atlantic and Indian Ocean. They are also beginning to appear in smaller areas, such as the North Sea, Greenland and the Barents Sea.


According to estimates, 300 billion tiny pieces of plastic are currently floating in the Arctic. The Atlantic Ocean currents bring waste there mainly from North America and Europe. 

Plastic sea pollutionPlastic sea pollution 

Even the deepest depths and uninhabited virgin beaches are affected

Some other studies estimate that up to 70% of plastic waste will end up on the seabed and in the ocean depths. Even at the deepest natural point on the planet, the Mariana Trench (nearly 11 km deep), researchers found a plastic bag.


Unspoilt deserted bays are not immune to plastics. In 2015, Jennifer Lavers, along with researchers from the Institute for Marine and Antarctic Studies (IMAS), discovered 20 tons of plastic waste on the uninhabited Henderson Island in the Pacific Ocean.


In fact, at one place, 672 pieces of waste per square metre were counted.  Henderson Island is on the list of UNESCO protected areas, because of the lack of drinking water it is uninhabited, and so not directly impacted by human activity. 

What waste is most encountered at sea?

The authors of the study, Plastic Pollution in the World's Oceans, recorded what waste ends up in the seas. Often they encountered roll-on deodorant balls, toothbrushes, buckets, bouncy balls, plastic bottles and beach footwear.


Disposable plastic packaging is the most common item found on beaches. Other items to be found included drink bottles, straws, disposable shopping bags, ladies' sanitary pads, tampons, cotton earbuds, condoms, cigarette butts and disposable lighters.


Fishing equipment often ends up in the sea, the so-called "ghost nets". Forgotten, lost or otherwise discarded fishing equipment accounts for up to 10 percent (640 thousand tons) of all marine waste.


In 2004 members of the project GhostNets Australia found and collected over 13,000 lost fishing nets in the area to the north of Australia. A study published in the journal Conservative Biology shows that 4866 to 14,600 turtles were caught in these "ghost nets".

Green sea turtle entangled in a discarded fishing netGreen sea turtle entangled in a discarded fishing net 

How does waste kill animals?

According to the United Nations, every single year, plastic waste kills up to a million seabirds, 100,000 marine mammals, sea turtles and countless fish.

The Internet has long been flooded with images of tortoises spewing up plastic bags, and seahorses holding onto cotton earbuds. And the evidence is mounting.

In the autumn of 2018, Cetaceans washed up dead on the beach of the Indonesian island of Sulawesi had nearly 6 kg of plastic in their stomachs. Among other things, flip-flops, plastic bottles, shopping bags, more than a hundred disposable cups and over thousands of plastic fragments.

  • It is reported that more than 40% of the existing whale, dolphin and porpoise species, all sea turtle species and approximately 36% of seabirds have ingested marine litter . Afflicted animals have their stomach filled with plastic debris and then literally die of starvation.
  • Fish, turtles, seabirds and mammals are captured in old fishing gear in so-called "unwanted catches." According to the non-profit organization World Animal Protection, this kills 100,000 whales, fish, seals, turtles and other sea life.
  • Plastics in the water also causes harm in another way. It acts as a magnet for oily and dangerous substances, which poison the fish and then the person whose plate they end up on.
  • There are some chemical substances contained in plastics that act as a poison, weakening or killing marine animals. It can be carcinogenic or negatively affect reproductive organs, which further threatens the population of fish, birds and other animals.
  • Floating waste can also serve to spread invasive species.
  • In many areas, plastic concentrations are up to seven times higher than zooplankton concentrations, as demonstrated by research from Algalita, an independent California-based marine research institute.


The plastics that most pollute the seas and oceans are not even visible. About 92% of the more than five trillion pieces of plastic waste floating on the surface form so-called microplastics. These are small particles with a diameter of up to 5 millimeters. They pose a serious problem not only at sea, as they can be found in large quantities in drinking water.


The toughest race in the world the Volvo Ocean Race is an agreeable combination of sport, science and ecology. A global map of microplastics was created at the event itself. According to this map, the highest levels were measured in the South China Sea, with an incredible 349 particles per m3. Even European waters are problematic with 307 particles per m3.


Microplastics are hidden in up to 80% of tap water. And how do they get into the water? One possible way is from washing clothes which contain microfibres. These are such materials as fleece, nylon, waterproof fabrics and fabrics used to produce sportswear. Microplastics are also contained in cosmetics, such as various skin peels and shower gels.

Time to change

The oceans are also struggling with a host of other major problems. Numerous toxic substances in the water threaten to cause irreversible damage to the balance of the ecosystem. An urgent problem is unregulated fishing and overfishing of some species. But the biggest threat to the ocean is undoubtedly climate change.


A number of non-profit organizations and projects are dedicated to protecting the oceans, education and training. National authorities and the international community are aware of the problem and have been discussing possible measures.

Dream scene with beautiful white sand beachDream scene with beautiful white sand beach 

What can sailors do to help?

Can sailors make change themselves? Surprisingly it’s very easy. Below we have handy tips for novices that won’t complicate life aboard the boat. Every step counts and these tips cost your almost nothing.


  • Do not leave any plastic utensils or bags loose on board. They can easily blow away. If it's possible, avoid plastic on the boat altogether.
  • Do not throw cigarette butts into the sea. Besides being plastic, the captured pollutants destroy corals.
  • Sort your waste. Plan stops at eco friendly marinas where they handle waste.
  • Ideally, of course, it best to not produce waste at all. Choose packaging that doesn’t use disposable plastic, use cloth bags and buy in markets locally.
  • Don’t use coral-destroying sunscreen. Replace with creams based on mineral filters, such as zinc.
  • Bring biodegradable, non-perfumed detergent on board. There are several on the market that can handle the greasiest of pots and pans.
  • Try to buy bigger containers rather than small plastic (PET) bottles. They will fit comfortably in the locker and each crew member can fill their own bottle with fresh water.
  • If you have children or love mixed drinks, bring a stainless steel straw instead of a plastic one.
  • Actively engage in beach and ocean cleaning. Whether within a wider group or just on your own.


There are dozens of tips and tricks for a wasteless and environmentally responsible behaviour, and most of them can be easily applied to boat voyages. Gradually try more ecologically responsible steps, even if there are still more fish in the ocean than plastic waste.


No matter what, you’ll be happy to see the impact of these efforts with your own eyes, whether it be clean white beaches or swimming and snorkelling in a crystal-clear turquoise sea.



1) Plastic waste inputs from land into the ocean by Jenna R. Jambeck, Roland Geyer, Chris Wilcox, Theodore R. Siegler, Miriam Perryman, Anthony Andrady, Ramani Narayan, Kara Lavender Law dostupné online

2) Ocean conference

3) Dailymail

4) Production, use, and fate of all plastics ever made by Roland Geyer, Jenna R. Jambeck and Kara Lavender Law, dostupné online

5) Plastic Pollution in the World's Oceans

6) Exceptional and rapid accumulation of anthropogenic debris on one of the world’s most remote and pristine islands, by Jennifer L. Lavers and Alexander L. Bond, dostupné online