The seizures at Bridlington also followed a national recall for the squishy toys, external, which was issued by the government earlier this month.
The Office for Product Safety and Standards said the items presented a “serious chemical risk” after they were found to contain Benzene, which can cause cancer.
The chemical can also cause irritation to skin, eyes, nose and throat as well as a burning feeling if it is ingested.
Councillor Lyn Healing, East Riding of Yorkshire Council’s cabinet member for communities and public protection, said: “Consumers have a right to expect that the products they buy are safe and genuine.
“Counterfeit and unsafe goods can present significant risks, particularly when they are aimed at children.”
The council said Trading Standards officers would be carrying out further inspections at car boot sales, markets and other retail outlets across the region.
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