Microplastics around UK coastline at levels nearly 100 times greater than five years ago, research shows

Microplastics have been found around the UK coastline at concentrations nearly 100 times greater in some places than five years ago, new research shows.

A new study by rowers and the University of Portsmouth found an average of 20 microplastic particles per cubic metre at 27 sites around the country, compared to between zero and 1.5 per cubic metre in a study in 2017.

The highest levels - 121 per cubic metre - were found in the Thames, with waters off the west coast of England coming second worst at 65 per cubic metre. None were found off the coast of northwest Scotland or the North York National Park.

The researchers said the increase in the detection of microplastics is because smaller sized particles have been captured in the steel filters used for the new study - providing a more accurate picture of the levels of pollution.

The tiny particles of plastic are defined as being anything smaller than 5mm in diameter and are found across oceans and land as larger pieces of plastic are broken down. This new survey has now exposed the true extent of the pollution in coastal waters and inland along the River Thames.

The samples were collected last year by the GB Row Challenge, a 2,000-mile race around Great Britain. A customised system was designed to pump water through a filter, which was changed daily, and the water samples were later analysed by a team at the university.

This method was capable of collecting much smaller plastic - with almost all of the particles less than 0.3mm in diameter.

Dr Fay Couceiro at the University of Portsmouth told The Times: “There is currently no complete map for the UK concentrations of microplastics in our coastal waters. These comparisons really show the need for a comprehensive map of these smaller sized microplastics and an annual monitoring method.”

“The data collected by GB Row Challenge will greatly enhance our understanding of conditions in the seas around the UK. The equipment used to collect data during the event has enabled us to capture much smaller particles – so we have been able to get a more accurate picture of where and how concentrated microplastics are.”

She added: “Over time it will significantly improve our understanding of the challenging problem of microplastics in our water.”

The GB Row Challenge team also recorded sound from high frequency noises such as dolphin echolocation clicks to lower frequencies such as boats. They collected environmental DNA too, with hopes to give scientists a clearer idea of the extent of marine life around the UK’s coast.

The impact of microplastics on the environment is well known, however more research is needed to understand the impact on human health.

In recent years several studies have found evidence of microplastics entering the human body with tests detecting particles in blood, placentas and breast milk.

The risk may vary according to the type of material, as plastics undergo chemical treatments during manufacturing to give them the properties needed for a particular use.

The average person is said to ingest around 50,000 microplastic particles a year through food and drink, according to research published in the journal Environmental Science and Technology in 2019.