Salmonella had been found previously at least 12 times in products made at the plant, but production lines were never cleaned up after internal tests indicated contamination, a government report said. The tainted products initially tested positive, were retested and then shipped out.
That happened as recently as September. A month later, health officials started picking up signals of the salmonella outbreak, which now has been linked to at least eight deaths.
Peanut Corp. of America's plant in Blakely, Ga., had 10 separate problem areas, Food and Drug Administration inspectors said in a report posted on the Internet.
"Here's a company that knew it had salmonella in a product and still released it," said Michael Doyle, head of the food safety center at the University of Georgia. "What they tried to do is get around it by having it tested elsewhere. But that doesn't count. The first time counts. They were selling adulterated products."
Separately, senior congressional and state officials on Wednesday called for a federal probe of possible criminal violations at the plant.
The company's actions "can only be described as reprehensible and criminal," said Rep. Rosa DeLauro, D-Conn., who oversees FDA funding. "This behavior represents the worst of our current food safety regulatory system."
In Georgia, the state's top agriculture official joined DeLauro in asking the Justice Department to determine whether the case warrants criminal prosecution.
"They tried to hide it so they could sell it," said Georgia Agriculture Commissioner Tommy Irvin. "Now they've caused a mammoth problem that could destroy their company -- and it could destroy the peanut industry."
There was no immediate response from Peanut Corp., which owns the processing plant at the center of the investigation. The company has previously said it fully cooperated with the salmonella investigation.
More than 500 people have gotten sick in the outbreak, which is continuing, and has been linked to at least eight deaths. More than 400 products containing peanut butter or peanut paste have been recalled. They range from Asian-style cooking sauces, to ice cream, to dog treats. However, major national brands of peanut butter are not affected.
Among the latest additions to the recall list were peanut butter cookies and cookie dough sold by fundraisers at 162 California schools. The products were made by Dough-To-Go Inc. and distributed throughout the state.
The peanut industry also condemned the company, portraying it as a rogue operator. The FDA's findings "can only be seen as a clear and unconscionable action of one irresponsible manufacturer, which stands alone in an industry that strives to follow the most stringent food safety standards," Patrick Archer, president of the American Peanut Council, said in a statement.
The FDA inspection report is preliminary, and the agency said the findings do not represent a final judgment on the company's compliance with food safety laws and regulations.
But the report detailed problems which food safety experts say would be of concern. The roaches were found in a wash room next to a packaging area. And a sink used for cleaning utensils also was used to wash out mops.
Of even greater concern, inspectors found open gaps as large as a half-inch by two-and-a-half feet at air conditioner intakes on the roof of the plant. Water stains were seen on the ceiling around the intakes and near skylights. The openings were above an area in which finished products were handled. Water leaks would be a problem because salmonella thrives in moist conditions.
A leaky roof is believed to have contributed to a 2007 salmonella outbreak in Peter Pan peanut butter.
ConAgra, the manufacturer, said the plant's roof leaked during a rainstorm, and the sprinkler system went off twice because of a problem, since repaired. The moisture from those three events mixed with dormant salmonella bacteria in the plant that the company said likely came from raw peanuts and peanut dust.
Inspectors at the Blakely plant also found that Peanut Corp. did not take proper steps to prevent finished products from being contaminated by raw peanuts. Roasting is supposed to kill the bacteria, but raw peanuts can harbor salmonella.
On the Net: FDA's recall page: http://tinyurl.com/8srctw