A senior US senator has called for all toys being imported into the country from China to be inspected after a massive recall by toymaker Mattel.
Dick Durbin accused China of having "lax safety standards" and said that toy firms should voluntarily allow third-party inspectors to check goods.
On Tuesday, Mattel recalled more than 18 million toys worldwide, the second such operation in two weeks.
This followed the discovery that paint used on some toys may contain lead.
Chinese-made Sarge die-cast toys from the Pixar film Cars have been recalled.
Mattel has also said that some toys, including Polly Pocket, Batman Magna, Doggie Daycare and One Piece playsets, contain small magnets that can come loose.
Concerned parents in the UK are being advised to take the recalled items away from their children.
They should then contact Mattel's helpline on 01628 500 303, e-mail HelplineUK@mattel.com or visit the company's UK website at www.service.mattel.com/uk/.
Customers elsewhere can obtain details of who to contact at http://www.mattel.com/safety.
The Consumer Products Safety Commission (CPSC) said it had no reports of any injuries from the recalled products.
The earlier recall of 1.5 million toys was by Mattel's Fisher Price unit.
'Time to act'
"We can't wait any longer for China to crack down on its lax safety standards," said Mr Durbin, a Democrat senator.
"This needs to stop now before more children and more families are put at risk."
He added: "This problem is serious, and I think that we should temporarily detain and inspect all shipments of children's products from China that contain paint.
"The time to talk is over. It's now time to act."
China said that it had launched an investigation into the recall with the General Administration of Quality Supervision, Inspection and Quarantine saying it was watching the issue closely.
Earlier it pointed out that of the billions of goods it produces every year, only a fraction are found to be faulty.
It is unclear exactly when the latest problem was discovered, but an unnamed source from the China Toy Association told Reuters news agency that it was aware of the problem with lead in paint as long ago as March.
The BBC's Quentin Somerville said that Beijing had been quick to act after the first recall, revoking the licence to manufacture goods of a firm in Guangdong province.
"The government doesn't normally act so quickly, but it recognises that people could lose faith in the Made in China label very quickly," he said.
"The country's wealth depends on exports."
Mattel has recalled 253,000 Sarge toy cars in the US and 183,000 from the rest of the world.
Mattel said that 49,000 of the affected vehicles were in the UK and Ireland.
The company blamed the amount of lead in the paint on a subcontracted Chinese company called Hong Li Da using paint from unauthorised suppliers.
The recall is the latest in a series of alerts about Chinese products in the US, raising fears in Beijing that the "Made in China" label is being seriously damaged.
Chinese officials have announced a series of measures to try to tackle the problems, but analysts say that China's economy has grown so rapidly over the past two decades that addressing the issue will take a long time.