Disney officials said in a statement that they were working with the manufacturer, Advance Publishers of Maitland, Fla., to look into the matter.
"The safety of products bearing the Disney name or our characters is of utmost important to us," the company said. "We require that all Disney products must be tested by our licensees and manufacturers, and that they comply with all laws before being shipped. We are currently in contact with our licensee, Advance Publishers, to ensure that these bags were tested and are in compliance."
Calls to Advance Publishers were not returned.
Teena Massingill, a spokeswoman for Safeway, said the supermarket no longer sells the bags.
"They were available for just a few short weeks last year, and we sold less than 2,000 nationwide," she said.
Disney and the manufacturer have 60 days to respond to the notice sent Jan. 11, Margulis said. Depending on the response, the agency may drop its concerns, reach a negotiated settlement with the companies or sue to stop distribution of the goods under Proposition 65, a California consumer protection law.
The concern about Disney bags comes two months after the Associated Press performed a study finding that collectable glasses sold by Warner Bros. contained high levels of lead and cadmium, both linked to problems in childhood development.
In December, the Consumer Products Safety Commission found those glasses were not subject to federal child safety regulations because they were marketed primarily to adult collectors.
Alex Filip, a spokesman for the commission, said the glasses are thick, "highball-type" glasses sold for $30 in sets of four.
"We took a look at how they are marketed, sold and displayed, and determined they are not children's products," Filip said.
The commission has forwarded the complaint regarding the reusable Disney shopping bags to the Food and Drug Administration to determine the appropriate course of action, Filip said.