US pharmaceutical firm Abbott Labs is recalling nearly five million containers of powder baby formula contaminated by beetles or beetle larvae, the firm said Wednesday.

The recall affects cans and plastic canisters of the popular Similac powder formula sold in the United States, Guam, Puerto Rico and some Caribbean countries, a statement said.

"Abbott is recalling these products following an internal quality review, which detected the remote possibility of the presence of a small common beetle in the product produced in one production area in a single manufacturing facility," the company said.

"There is a possibility that infants who consume formula containing the beetles or their larvae, could experience symptoms of gastrointestinal discomfort and refusal to eat as a result of small insect parts irritating the GI tract."

The firm said there was no immediate health risk and added it was "implementing a plan to address this matter" at the affected facility.

"Abbott understands that parents expect to feed their children only the highest quality product," said Holger Liepman, executive vice president of Abbott Nutrition, apologizing for the contamination.

Abbott's shares fell 0.3 percent on the New York Stock Exchange.