Microplastics

One of the most insidious forms of marine plastic pollution comes in the form of microplastics.

Although plastic does not biodegrade, it does break down into smaller and smaller pieces in the sea. It becomes brittle through exposure to sunlight and is smashed by the waves against sand and rock.

Microplastics are pieces of plastic that are less than 5mm in size, meaning it is essentially impossible to remove from the environment. They are now found everywhere from the sea surface down to seabed sediments, and even locked into Arctic ice.

They are also just the right size to be consumed by many small sea creatures, particularly filter feeders. Shellfish, worms, crustaceans and coral all consume microplastics. The smallest pieces are even ingested by zooplankton, the foundation of the whole marine food chain.

These undigestible plastic fragments can not only bung creatures up and prevent them from obtaining sufficient nutrition to thrive. They also attract toxins from the surrounding seawater, and these accumlate in the animals’ body tissues. These can release a range of toxins with a damaging effect on reproduction, the nervous system and other functions. These effects are biomagnified further up the food chain in higher creatures that feed on these little ones, including commercial fish species.

Nurdles 

All plastic starts out as nurdles - pellets of plastic resin that are melted down and formed into all the plastic items we use today. 

The number of nurdles (sometimes known as 'mermaids' tears') made and shipped around the world each year is truly mind boggling, at over 100 billion kilos (5.5 quadrillion nurdles!) Large numbers of them end up in the sea, either because they are lost down drains in plastics factories, or are released from spilled shipping containers.

Unfortunately, nurdles look a lot like fish eggs – which form a large part of the diet of many marine creatures.

In the UK, a voluntary industry scheme to prevent pellet loss called Operation Clean Sweep, encouraging companies to adopt measures to improve handling, transport and use of pellets, has been in place since 2009 - but so far only 53 out of over 3,000 companies have signed up to it!

Ingenious RPBC member Rob Arnold has recently invented a machine to help separate microplastics from sand and seaweed. Over the spring of 2017 we worked with Rob to collect many millions of nurdles, biobeads and other microplastics from Tregantle beach on Whitsand Bay, highlighting the plastic industry's contribution to the marine debris problem. The particles may be tiny, but numerically nurdles make up one of the biggest types of litter out there.

Biobeads

In 2016 we discovered that more than half of the pellets on our beaches are in fact biobeads - a wrinkly or knobbly type of nurdle (designed to have a larger surface area) used in the wastewater treatment process. Biobeads are tiny plastic pellets used in at least 55 wastewater plants around the country to filter sewage, with nine of these plants in the South West Water area. Biobeads account for over 50% of all the industrial pellets on Cornish beaches that we have sampled so far, with many millions collected by our volunteers. Biobeads can accidentally escape from wastewater plants, either in large numbers through catastrophic spills, poor handling procedures, and – at least at one Cornish plant we have monitored – apparently through ongoing low-level losses. 

After many months of research, we produced a report on behalf of the Cornish Plastic Pollution Coalition called Biobead pollution on our beaches. What we know so far… We still don’t know enough about the pathways for losses (for example, they could also be lost through spills in transportation). However, it is clear that this system is too vulnerable, and there is no mechanism in place to effectively trap large numbers of beads in the event of a catastrophic spill. 

We hope the report will be useful for increasing understanding of how plastic biomedia, particularly biobeads, are used in wastewater treatment plants, and lead to measures to minimise their potential environmental impact.

The full report can be downloaded here.

Plastic filaments

Many of our clothes are now made from synthetic fibres. In fact many of them, such as fleeces, are often actually made from recycled domestic plastic.

Each of these garments will shed thousands of plastic microfibres each time they are washed – and these end up being flushed straight down the drain.

Like other micro plastics, the fibres are impossible to retrieve from the environment.

Cosmetics

Incredibly, large number of the body scrubs, facial exfoliants, toothpastes and other cosmetics contain tiny plastic granules, designed to be washed straight down the drain after use.

Many large companies such as Unilever and Procter & Gamble have pledged to start phasing out the use of these micro-beads - but many others have not.

The UK Government has recently announced a ban on the sale of these microbeads from the end of 2017, following in the footsteps of the United States and Canada.

In the meantime, make sure to only use products containing natural exfoliants, such as pumice, salt and apricot kernel. You can find out more about the problem on the Beat the Microbead site, and also see which products are safe to use.