McGuinness has also warned the clean-up would be “long and expensive”.
“Sadly, it is already clear this looks like the worst incident of nurdle pollution in Europe,” she said.
South Tyneside and North Tyneside councils said they have been working long hours around the tides to clear the beaches.
On Thursday, the charity Nurdle arrived in the North East to help with the clear up effort.
Using “nurdle machines”, which look like vacuums, they began sucking up the plastic pellets and sand.
South Tyneside Council said the pellets will then be sieved out of the sand so they can collate exactly how many have been found on each beach. The sand will be returned to the beaches.
Members of the public are still being urged to keep away from the clean-up.
But director of environment at North Tyneside Council, Samantha Dand, said it was still safe for people to enjoy the region’s beaches.
“Make sure you’re following the advice that’s obviously on our signage, that’s on our council website,” she said.
“Make sure though that you do keep dogs on leads because these pellets can be quite hazardous to wildlife and animals and yes, just come down and enjoy our fabulous beaches.”
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