Go Go Hamsters are made in China but are sold worldwide as Zhu Zhu Pets. They've been so popular as a toy for Christmas this year that many shops have sold out.
Who said they're not safe?A San Fransisco company, GoodGuide, which tests household products for chemicals, reported that the toys had high levels of the metals antimony and tin.
Dara O'Rourke, founder of GoodGuide, said: 'Antimony has potential health hazards related to it which, if ingested in high enough levels can lead to cancer, reproductive health and other human health hazards.' On the GoodGuide website it says tin can be harmful to the immune and nervous system.
What have the distributors said?Russ Hornsby, the CEO of Cepia, who distribute the Go Go Hamsters in America, rejected the claims from GoodGuide - saying: 'We want to assure everyone already enjoying Mr Squiggles or other Zhu Zhu Pets, and those planning to purchase Mr Squiggles or another Zhu Zhu Pet this holiday season, that the toy is 100% safe and in compliance with all US and European toy safety standards.
'I have been in the toy industry for more than 35 years, and being a father of children myself I would never allow any substandard or unsafe product to hit the shelves.
'That's why we always test to not only meet but also exceed safety standards.'
The UK distributor of the toys also say they are 'confident' that Mr Squiggles and the other Go Go Hamsters are safe. Jon Diver, Managing Director for Character Options said: 'The pets are tested in independent accredited laboratories during the manufacture and again before shipment through our own internal diligence programme. Their safety has always been ratified.'
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