(CNN) -- Pfizer is recalling an additional 38,000 bottles of the cholesterol-fighting drug Lipitor after reports of an odor linked to the packaging bottles, the drug company said in a statement.
The recall will affect Lipitor 40 mg tablets (atorvastatin calcium) distributed in the United States. The company said the bottles were supplied by a third-party manufacturer.
"We have thoroughly evaluated the root cause, which is episodic exposure of the bottles to low levels of TBA (tribromoanisole) as they are shipped or stored," Pfizer said. The company said the rate of odor complaints was fewer than three per million bottles.
Earlier this year, Pfizer recalled of more than 190,000 bottles of Lipitor due to similar odor-related complaints.
"Research indicates that a major source of TBA appears to be 2, 4, 6-tribromoanisole(TBP), a chemical used as a wood preservative," the company said. "Although TBP often is applied to pallets used to transport and store a variety of products, Pfizer prohibits the utilization of TBP-treated wood in the shipment of its medicines."
Pfizer said a medical assessment found the risk of health consequences to patients appears to be minimal.
According to the Food and Drug Administration, reports of drug contamination have been linked to a "moldy or musty" odor in food and wine products.
"Currently available data indicate that serious adverse health effects have not resulted from ingestion of drugs or foods contaminated," the FDA said, with such compounds at the levels of contamination that have been reported.
But the agency noted another problem that could stem from contaminated drugs.
"Even if the health effects are minimal, [the] FDA is concerned that patients sensing an unusual odor that is not intrinsic to the product will stop taking their medication," the administration said on its website.
Pfizer said it does not expect a product shortage resulting from the new recall. Anyone with questions can call 1-888-LIPITOR.
CNN's Rick Martin contributed to this report.