Almost three-quarters of UK beaches are littered with harmful tiny plastic pellets that can kill wildlife, a survey has found.
The lentil-sized pellets known as "nurdles" are used to make plastic products.
Searches of 279 shorelines in spots ranging from Shetland to the Scilly Isles have revealed 73% of the sites scoured had the industrial pellets on them.
The largest number recorded in the Great Winter Nurdle Hunt weekend in early February were found at Widemouth Bay, Cornwall, where 33 volunteers from the Widemouth Task Force collected around 127,500 pellets on a 100-metre stretch of beach.
Hundreds or even thousands of the tiny pellets were spotted by volunteers over a short period of time in locations from Porth Neigwl, Wales, to the shoreline on the Isle of Wight.
They can escape into the environment throughout their manufacture, transport or use, spilt into rivers and oceans or getting into drains where they are washed out to sea.
Billions of the small, light-weight nurdles are lost in the UK each year.
Overall, more than 600 volunteers took part in the Great Winter Nurdle Hunt organised by Scottish environmental charity Fidra in collaboration with the Environmental Investigation Agency, Fauna & Flora International, Greenpeace, the Marine Conservation Society and Surfers Against Sewage.
They are one of the main sources of "primary microplastics" - small pieces of plastic which have not come from larger items broken down into little bits - in European seas and can cause damage to wildlife, such as birds and fish which eat them.
Experts warn the pellets can also soak up chemical pollutants from their surroundings and then release the toxins into the creatures that eat them.
Results from the hunt, which was backed by local community groups and charities, will be fed into the Government's consultation on microplastics, looking at ways of tackling the problem.
Dr Madeleine Berg, projects officer at Fidra, said she was delighted so many volunteers took part.
"The information we've gathered will be vital to show the UK Government that pellets are found on beaches all around the UK", she said.
Dr Berg added: "Simple precautionary measures can help spillages and ensure nurdles don't end up in our environment."