"Due to possible lead contamination, this product (Ugly Teeth) has been recalled," Factory Card and Party Outlet said in a statement issued on the eve of Halloween.
Described as a "horribly realistic Halloween accessory to make your teeth look hideous", the Chinese-made "Ugly Teeth" are designed to be worn in the mouth by children dressing up for Halloween.
The teeth were analyzed by a team from Ashland University in Ohio looking into lead content in children's products.
"Lead paint is a problem when it's ingested by a child, so to have lead on an item that is designed to go into the mouth -- that's what's particularly horrifying about these teeth," said Dr Jeffrey Weidenhamer of Ashland University in Ohio, the team leader.
"We analysed the paint on the surface of the teeth. The orange teeth were the worst in terms of having six to seven percent lead by weight in the paint," Weidenhamer said.
"That's about 100 times the US standard on lead in paint which is .06 percent," he told AFP.
Lead can cause damage to the brain and nervous system of children, behavior and learning problems, slowed growth, hearing problems and headaches.
It is also potentially harmful to adults, in whom it can lead to reproductive problems, high blood pressure, digestive problems, nerve disorders, memory and concentration problems, and muscle and joint pain.
The "Ugly Teeth" were one of 54 Halloween products tested by Ashland and his team for lead.
"We initially tested 22 Halloween products for lead at the request of Ohio Senator Sherrod Brown, and followed up with 34 further tests to ensure that we had a significant sample set from which we could draw conclusions," Weidenhamer told AFP.
"We found contamination in six out of 54 products we tested, which is a little more than 10 percent," Weidenhamer said.
"The implication of that is: if 10 percent of the products on the shelves in these seasonal items contain lead paint, that's a lot of products out there that no one's aware of."
According to Senator Brown's office, more than 21 million toys and products made in China have been recalled since August because they contain dangerous levels of lead.
The latest findings by Ashland's researchers came hours ahead of the release of a report, co-sponsored by Brown, entitled "Toxic Trade: Globalization and the Safety of the American Consumer."
The report blames the huge influx into the United States of dangerous goods on a surge in out-sourcing by US manufacturers, looking to ensure the lowest possible production costs, and calls for stiffer checks and rules on imports to protect consumers, especially children.
Weidenhamer's team has reported its findings on the tainted teeth to the Consumer Product Safety Commission (CPSC), the federal watchdog in charge of recalls.
The CPSC has to conduct its own tests on a product before it can order a recall.
The safety watchdog has not yet ordered the teeth to be pulled from shelves around the United States, but is working "closely and urgently with the company involved," spokeswoman Patty Davis said.