Parts of cattle supposedly banned under rules enacted after the nation's first case of mad cow disease are making it into the human food chain, according to the union that represents federal inspectors in meat plants.
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The National Joint Council of Food Inspection Locals, which represents meat and poultry inspectors in federally regulated plants nationwide, told the U.S. Department of Agriculture in a letter earlier this month that body parts known as "specified risk materials" were being allowed into the production chain.
The parts include the brains, skulls, spinal cords and lower intestines of cattle older than 30 months. These body parts, thought to be most likely to transmit the malformed proteins that cause bovine spongiform encephalopathy, or mad cow disease, were banned from the human food supply by USDA officials last January.
The union based its Dec. 8 complaint on reports from inspectors in several states, though it declined to say which ones.
It said that the inspectors found heads and carcasses of some cows on slaughter and processing lines that were not always correctly marked as being older than 30 months. That age is the cutoff for rules governing the use of higher-risk materials in human food; any animal older than 30 months must have any such parts removed before it can be cut up into meat.
But plant employees responsible for checking the age of cattle were not always marking each older carcass. In the course of their regular work, inspectors on the processing lines checked cattle heads themselves and found some from older animals that had been passed through unmarked.
"We couldn't determine that every part out of there was from a cow under 30 months," Stan Painter, the union's chairman, told MSNBC.com. "There was no way to determine which one was which."
The government and the beef industry frequently point to the SRM ban, as it is known, as the single best measure to ensure that any meat possibly infected by mad cow disease is kept out of the human food supply. The ban was enacted this year after the first U.S. case of the disease was detected in a Washington state dairy cow in December 2003.
Research has shown that most of the risk from infected animals lies in neural tissue, such as the brain, not muscle meat. Mad cow disease has been linked to a related human disease; both are always fatal.
USDA spokesman Steven Cohen said the ban was working, as were age checks on cattle. "We feel very strongly that this is being done," Cohen said. "It's being done correctly, and it's being verified by the people whose job it is to do that."
Federal oversight for the age checks is usually performed by offline inspectors — usually a more senior inspector at a plant who handles larger issues such as food safety plans. They are directed to perform spot checks on plant employees who perform the age checks using paperwork as well as indicators such as the growth of the animals' teeth.
But current oversight would cover a small fraction of the total animals that pass through any given plant — just 2 percent to 3 percent, by the union's estimate.
In its letter, sent to the head of the USDA's Food Safety and Inspection Service, the union also reported that some inspectors were "told not to intervene" when they saw body parts of some older animals, sent for packing with those of younger animals. This is despite export requirements for certain parts that have been set by U.S. trading partners.
Specifically, the union said, kidneys from older animals were sent down the line to be packed for the Mexican market, which prohibits them from cows over 30 months. When the inspectors complained, Painter said, "The agency basically told the inspectors, 'Don't worry about it.'"
Cohen said the age checks, which are usually performed before slaughter, are meant to be handled by supervisors and veterinary medical officers. "It is not the online inspectors whose role it is to determine" an animal's age, Cohen said.
"The inspector on the line's role is to look for disease," he said. "If an online inspector feels as though something is not being done they should talk to their supervisors."
The online inspectors performed the checks on their own amid concerns that older animals were not being marked as such, according to the union and to an attorney familiar with the matter.
The cases referenced in the letter were apparently reported to supervisors and to USDA district offices, Painter said, but the inspectors were told, "Don't worry about it. That's the plant's responsibility."
The union has not yet received a response, he added. Cohen said the agency would have a response soon, and noted that the department's inspector general is auditing how well plants comply with the ban.
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