Shares in McDonalds dropped 1.5 per cent yesterday, knocking more than a billion dollars off its market value, after the toxic metal cadmium was discovered in its new range of Shrek-themed drinking glasses.
The burger chain announced a recall of 12 million of the glasses, which they had sold in the US and Canada for roughly $2 (£1.38) each, when the prohibited substance was discovered in paint used to decorate them with images of characters from the animated film.
Cadmium, a carcinogen which can cause kidney, lung, liver and bone damage, should never be used in products which could come into contact with food or drink. It is not known how the metal came to be in the pint glasses, which were originally supplied by a company from New Jersey called ARC International.
The scandal emerged after a Democratic Congresswoman, Jackie Spier, who has campaigned against the use of the substance in paint and jewellery, received an anonymous tip-off that it was being used in the promotional products. That was verified when the US Consumer Product Safety Commission carried out laboratory tests on glasses it bought in several of the company's branches.
"Our children's health should not depend on the consciences of anonymous sources," said Spier yesterday, after news of the discovery emerged. She added that the law should be changed so that all children's products are in future tested long before they hit the shelves.
McDonald's will be left facing an expensive bill for the recall. The chain will also be saddled with the consequences of legal actions related to the sale of the allegedly dangerous products, which were available in four designs depicting the characters Shrek, Princess Fiona, Puss in Boots and Donkey.
A spokesman for the fast food company said it was asking customers to stop using the glasses "out of an abundance of caution" rather than because they believed that cadmium, which is used to create red and yellow tones in paint, was present in a sufficient quantity to cause illness.
"We believe the Shrek glassware is safe for consumer use," the spokesman said. "However, again to ensure that our customers receive safe products from us, we made the decision to stop selling them and voluntarily recall these products effective immediately."
The US Consumer Product Safety Commission, which announced the recall yesterday, warned consumers to stop using the glasses; McDonald's said it would post instructions on its website next week regarding refunds.