Last January, an Associated Press investigative report found that many Chinese manufacturers were substituting the toxic metal cadmium for lead in children’s jewelry and toys after the U.S. Consumer Products Safety Commission effectively banned the use of lead in surface coatings and other products. Today, the CPSC and McDonald’s announced that the cadmium, used by some manufacturers because it possesses lead-like qualities, has turned up in millions of promotional Shrek drinking glasses.

The glasses were manufactured French company ARC International at a facility in Millville, New Jersey and were sold at McDonald’s restaurants nationwide from May 2010 into June 2010 for about $2. Approximately 12 million of the glasses were sold nationwide as part of the “Shrek Forever After 3D” movie promo.

The 16-ounce glasses come in four designs, each painted with a different character from the movie. The toxic metal cadmium was found in the paint on the exterior of the glasses. California Congresswoman Jackie Speier reported the glasses to the CPSC after receiving an anonymous tip. The CPSC approached McDonald’s with the matter and the fast food chain immediately recalled the glasses. Anybody who owns one or more of the glasses can return them to a McDonald’s establishment for a full refund.

Federal health authorities classify cadmium as a potent carcinogen and neurotoxin. Children exposed to just small doses of cadmium over a long period of time, such as by biting on a toy or piece of furniture, can eventually suffer from cumulative effects.

On the Centers for Disease Control and Prevention’s priority list of the 275 most toxic substances in the environment, the heavy metal cadmium is ranked seventh.

Although the CPSC has not yet established an acceptable level for commercial cadmium use, an agency spokesman said that the cadmium level in the Shrek glasses exceeded the levels that will be set by the government.

No injuries or illnesses have been linked to use of the drinking glasses.

“Our children’s health should not depend on the consciences of anonymous sources,” Representative Speier said in the statement. “Although McDonald’s did the right thing by recalling these products, we need stronger testing standards to ensure that all children’s products are proven safe before they hit the shelves.”