Under the microscope: Microplastics in the ocean

What are they, why are there microplastics in the ocean, and what action can we take?

Hands holding microplastics

The phrase “plastic pollution” conjures up images of mountains of discarded litter – but one of our biggest pollution problems is barely visible.

Microplastics are tiny pieces of plastic measuring 5 millimeters or less that can take a variety of forms, including fibers, fragments, beads, or pieces of film. Some are so small they can’t be seen with the naked eye. Yet despite their often microscopic size, their impact is huge – as they leach into our environment, posing a threat to marine health, and even entering the food chain.

In some cases, microplastics will start out as larger pieces of waste, such as household objects, which have eventually degraded and broken down into tiny pieces. Others are what’s known as “primary microplastics” and in fact start out as microplastics: these can include microbeads in cosmetic products or toothpastes, fibers used for fabric manufacturing, and industrial microplastics that have leaked from plants or factories.

The problem with microplastics in the ocean

When this plastic ends up in our environment, swirling around in our oceans, the effects can be catastrophic. Eight million tons of plastic end up in our oceans every single year, the equivalent of one garbage truck per minute.

So why are there microplastics in the ocean, and how do they get there?

It’s easy to assume the source of the ocean plastic problem is items littered at sea, from fishing or shipping perhaps. But, in reality, that only accounts for 20%. The other 80% starts out on land, and it’s all downhill from there – quite literally. Litter from rubbish bins, storm drains and landfill sites, as well as plastic waste flushed down the toilet (such as wet wipes or sanitary products, which contain plastic), can all end up in our waterways, and from there it can easily flow into the ocean.

Bigger things like plastic bottles, bags, lids and packaging will eventually be battered and broken down by waves, sun and marine life, scattering into trillions of tiny pieces that are too small to remove but resilient enough to remain in our oceans for years.

Food for thought

That’s just the start of the problem. What happens next is these minuscule particles end up everywhere – from the water we drink to the air we breathe. Birds mistake microplastics for food and feed them to their chicks. Marine mammals ingest them. Microplastics are making their way into the food chain and humans are eating tens of thousands of microparticles of plastic every year. To put that into context, we each consume the equivalent of a credit card worth of plastic each week, according to researchers.

We also now know it’s possible for microplastics to get into other parts of our bodies. This year, for the first time, microplastics were found deep in the lung tissue of living people. The findings were revealed in a study published in Science of the Total Environment, and the most common types of plastic found were PET (polyethylene terephthalate, often used for plastic drinks bottles) and polypropylene (used for packaging and pipes).

Seeing is believing

Infographic Antarctic circumpolar current

“Garbage patches” are large volumes of ocean plastic that can accumulate in what are known as gyres, as a result of wind, tides and temperatures. There are five major areas in the world’s oceans where these gyres can be found.

Kristine Berg is Sustainability Manager at global resource sustainability company TOMRA, and wanted to see the scale of this pollution first hand to better understand ocean plastic and spread the message about the urgency of tackling marine litter. On two occasions she has sailed to these oceanic gyres with the all-female ocean plastic research organization eXXpedition (which has been sponsored by TOMRA), which has a goal of “exploring the impact of and solutions to plastic and toxic pollution in our ocean”.

Contrary to popular belief, these garbage patches are not big islands of trash solid enough for you to stand on. In a way it would be better if they were, says Kristine, perhaps surprisingly. She explained: “If these gyres were solid there might be a way to try and tackle them by trawling them and scooping up the litter. But they’re not – they are a microplastics soup."

Just imagine trying to pick up soup with a fork and you’ll understand the challenge of tackling microplastics in the ocean. We’re talking about millions of microscopic pieces of plastic, so how do you even begin to clean up? Seeing the scale of the problem and realizing we’ll never see plastic-free oceans again took a real emotional toll on the crew – it was heartbreaking.

Kristine Berg TOMRA Sustainability Manager

What surprised Kristine was that the further she got from land, the more plastic she saw, which seemed counter-intuitive. At one point their vessel was closer to the International Space Station than it was to any land mass, but the litter kept coming.

Kristine said: “When you’ve sailed for ten days, it seems like forever, and you lose concept of time and distance. But we kept seeing items like toothbrushes, toilet seats, washing baskets and takeaway menus floating by. It was bizarre to think we were thousands of nautical miles away from any other people, islands, or boats yet we were seeing things from someone’s bathroom. Unbelievably, at our furthest point from land, we found the highest number of plastic particles in our trawl samples.”

Remembering “litter” can be a resource

There is no “silver bullet” that will fix the ocean plastic problem, and while coastal clean-ups play their part in stopping litter reaching the ocean, action needs to start on land before waste reaches that point. At TOMRA, we believe that we all need to change our habits and re-frame our thoughts so that we take better care of our environment and turn off the tap to plastic pollution.

“If your kitchen is flooding, cleaning up is not the first thing you do. You stop the flooding at the source by turning off the tap. We need to do the same with plastic pollution,” Kristine explained. “Tackling the problem at an earlier stage, to prevent plastic ending up the ocean in the first place, is essential if we want to make a real impact.”

Image of plastic bottles on shoreSmall things can make big difference when it comes to reducing pollution from microplastics – thinking twice about the plastics we flush down the toilet, considering the ingredients that are in our toiletries and cleaning products, or using filters to stop microfibers getting into our waste-water.

Crucially, we must stop treating plastic as trash and remember that, in many cases, it can be a vital resource we can reuse and recycle.

For example, more than 1.4 trillion beverage containers are sold every year, 500 billion of which are plastic. Too many needlessly end up as landfill or litter. Plastic bottles and caps were the top two and fives types of litter collected in the International Coastal Cleanup in 2020, which examined more than 8 million pieces of litter from over 50 countries. However, most plastic bottles are made of the valuable and highly recyclable materials PET and HDPE, so it is vital to stop treating them like disposable items.

From trash to treasure

A range of different solutions need to be deployed if we want to turn the tide on plastic pollution and reduce microplastics in the ocean. Deposit return systems (DRSs) are one of the solutions that focus on the source of the plastic problem on land, and this tried-and-tested approach is proven to reduce landfill while allowing bottles and cans to be collected for recycling.

Image of couple shopping for cotntainersDRSs work by adding a refundable deposit to the price of drink containers at the point of purchase. Giving the empty beverage containers a monetary value incentivizes consumers to return them for recycling.

More than 40 markets across the globe have deposit return systems, with well-designed systems routinely collecting in excess of 90% of deposit containers sold. Governments in a number of new markets are moving to implement their own schemes.

In a DRS, containers are kept separate from other waste, avoiding contamination and ensuring materials maintain their purity and high quality. This means bottles and cans can be recycled into new ones, over and over again – in what’s known as a "closed loop".

TOMRA calls this process Clean Loop Recycling, and the aim is to keep beverage containers in that loop for as long as possible.

One part of a big picture toward combatting microplastics in the ocean

Only 2% of the world’s plastic packaging is recycled in a closed loop, so there is still much to be done when it comes to increasing recycling rates.

There are many solutions to preventing plastic from ending up in the oceans, and deposit return systems have a proven impact when it comes to tackling the problem of beverage container litter. Drink container litter, as a proportion of all litter, is 66% less in regions with a DRS compared to those without. Regions with a meaningful deposit value experience less beverage container litter as a proportion of all litter compared to deposit systems with a low deposit value or no deposit system.

Diverting larger pieces of plastic waste like drink containers from the litter stream means they won’t get the opportunity to degrade or end up reduced to microplastic particles. We all have a part to play – what might feel like a “micro” action from one person can contribute to a big change for the planet.

TOMRA Collection is the world’s leading provider of reverse vending machines for Clean Loop Recycling, to transform society’s habits and keep valuable resources in a continuous loop of use and reuse. Reverse vending machines automate consumer returns of beverage containers for recycling, including in deposit return systems. The company’s solutions collect aluminum, plastic and glass beverage containers to be continually reused and recycled back into new bottles and cans.

Turtle swimming in ocean