Nurdles are small plastic pellets about the size of a lentil and there are billions of them floating in the ocean.
Nurdles wash up on beaches in the UK - they’re ‘pre production plastic pellets’, a building block for other plastics, and the beads can be made from polyethylene, polyvinyl chloride or other plastics.
In the environment, they are ‘toxic sponges’, which attract chemical toxins and other pollutants from the seas.
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Anti-nurdle organisation The Great Nurdle Hunt says, ‘Like other plastics, nurdles can be mistaken for food by marine wildlife like seabirds, fish, and crustaceans.
‘Once polluting our environment, they can pose a threat to these creatures and habitats for years to come.
‘This is because nurdles are tiny, persistent and potentially toxic. Due to their size, and often clear colour, nurdles can look like fish eggs or other small animals which makes them particularly attractive to seabirds, fish and other marine wildlife.’
Tom Gammage, at the Environmental Investigation Agency (EIA), told The Guardian, ‘“The pellets themselves are a mixture of chemicals – they are fossil fuels..
“But they act as toxic sponges. A lot of toxic chemical are hydrophobic so they gather on the surface of microplastics.
“Pollutants can be a million times more concentrated on the surface of pellets than in the water. And we know from lab studies that when a fish eats a pellet, some of those pollutants come loose.”
Earlier this year, researchers warned of another worldwide plastic pollution problem which looks exactly like pebbles.
‘Pyroplastics’ are created when plastics are heated during manufacturing processes.
Researchers began to analyse the ‘rocks’ in recent years after people spotted them on beaches in Cornwall - initially thinking they were real pebbles.
The lumps of plastic also weather like real rocks, and shed microplastic into the environment.
Some of the lumps could be as much as half a century old, according to Andrew Turner of the University of Plymouth.
Turner writes, ‘Pyroplastics are derived from the burning of plastic. Some may look like various burnt pieces of plastic amalgamated together, while others look remarkably like pebbles once they have been eroded down by the elements.
‘They have probably been in existence since we started burning plastic to dispose of it (perhaps 80 years or so). Some of the now restricted chemicals we find in pyroplastics suggest they have been around since at least the 1960s.
‘Burnt plastic on beaches is likely to be derived from many sources, including burning waste on the beach itself, collapse of old landfill sites, historical burning of waste at sea and contemporary burning of plastic waste on small island states.’
Pyroplastics are found worldwide, with samples having been found on Atlantic beaches in Spain and the Pacific beaches of Vancouver.
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