s/r home  | issues  | authors  | 33 contents

Synthesis/Regeneration 33   (Winter 2004)

US Violates Global Standards
on Preventing Mad Cow Disease

by Michael Greger, M.D.,
Organic Consumers Association

The National Cattlemen’s Beef Association describes government and industry efforts to safeguard the American public from mad cow disease as “swift,” “decisive” and “aggressive.”

The world’s authority on these diseases disagrees. Dr. Stanley Prusiner is the scientist who won the Nobel Prize in Medicine for his discovery of prions, the infectious agents thought to cause bovine spongiform encephalopathy (BSE), or mad cow disease. The word Dr. Prusiner uses to describe the efforts of the US government and the cattle industry is “terrible.”

In 1996, in response to the revelation that young people in Britain were dying from variant Creutzfeldt Jakob Disease (vCJD), the human equivalent of mad cow disease, the World Health Organization (WHO) issued seven “Recommendations,” four of which were concrete prescriptions to reduce the likelihood of mad cow disease spreading to human populations. To this day, the United States government continues to violate each and every one of these four guidelines.

1. Stop feeding infected animals to other animals.

The number one recommendation of the World Health Organization was that no “part or product” of any animal showing signs of a transmissible spongiform encephalopathy (TSE), or mad cow-like disease, should be fed to any animal. Yet in the US it remains legal to feed deer and elk known to be infected with a transmissible spongiform encephalopathy called chronic wasting disease to livestock such as pigs and chickens.

The beef industry’s position is an illustration of circular reasoning: We don’t rigorously test because we haven’t found any cases.

Although science has yet to investigate whether pigs and chickens are susceptible to “mad deer” prions, there is a concern that even if these animals don’t develop clinical symptoms of the disease, they could become so-called “silent carriers.” Dr. Richard Race is a Senior Investigator with the National Institutes of Health. In 2001, he published a landmark paper showing that even species thought to be resistant to particular strains of prions could invisibly harbor the disease and pass it on to other animals. He also found that these deadly prions were somehow able to adapt to the new species, becoming even more lethal and replicating faster and faster.

The reason Dr. Race is so concerned is because chronic wasting disease (CWD) seems unique in that it’s the only prion disease thought to be spread by casual contact between deer through exposure to, or exchange of, bodily fluids such as saliva. And the best available research suggests that CWD prions can infect humans as well, perhaps even as readily as mad cow disease can. Dr. Race wonders if people could become silent carriers as well. All transmissible spongiform encephalopathies are invariably fatal. Consumer advocates argue that these prions should not be allowed to enter into the food chain.

In May 2003, the Food and Drug Administration finally drafted proposed voluntary “suggestions” for the rendering industry, recommending that deer and elk infected with chronic wasting disease, or at high risk for the disease, be excluded from animal feed. However, even if this proposal is enacted, it represents only non-binding, non-enforceable “guidance” recommendations for the industry.

2. All countries need to establish adequate testing and surveillance.

The World Health Organization’s second guideline was for all countries to establish adequate testing and surveillance for mad cow disease according to the standards set down by the Office International des Epizooties (OIE), World Animal Health Organization. The OIE’s International Animal Health Code recommends, in Article, that, “Cattle that have died or have been killed for reasons other than routine slaughter (including ‘fallen’ stock and emergency slaughter) should be examined.” This is where the United States (and Canada) fall seriously short.

The combination of these two populations, “fallen stock and emergency slaughter cattle,” is essentially equivalent to the US nonambulatory, or “downer” cattle population. Every year, an estimated 195,000 to a million cattle collapse in the US for largely unknown reasons and are too sick or injured to rise. Even though these downed animals are not even fit to stand, an investigation of USDA slaughterhouse records showed that most of them are still ruled fit enough for human consumption. Over the past 10 or so years, though, the USDA has tested less than 2% of the downer cattle in United States. And, those tests were almost exclusively limited to animals that were sent to slaughter. The US tests even fewer of the downer cattle on farms and ranches that never make it to the slaughterhouse, considered the single highest risk cattle population in the United States. These dead, dying or downed cattle can still then be fed to other livestock. It’s no wonder that Dr. Prusiner describes the number of tests done by USDA as “appalling.”

The beef industry’s position is an illustration of circular reasoning: We don’t rigorously test because we haven’t found any cases. Less than half of American dairy cows make it past their fourth birthday, before being retired into hamburger meat. In fact, the majority of US cattle are slaughtered before they reach age two. While this may mean that the prion load in an infected animal may be less at slaughter (since prions accumulate with age), it also means mad cow disease may be harder to detect in the United States.

…based on the Canadian case, it is “likely” that mad cow disease is also present in the United States.

Another country that was ruled just as unlikely as the United States to have mad cow disease was Canada. Saying Canada has mad cow disease is not far from saying the United States does, because the cattle industries of both countries are fully integrated across an open border. Every year, the US imports over a million head of cattle and billions of pounds of beef from Canada. How can the US still call itself BSE-free when over three quarters of Canadian cattle exports end up in the United States?

Dr. Bruno Oesch of Zurich University recently told the BBC that US consumers may well have been eating infected beef for some time now. The New Scientist, a weekly British science digest, reports that, based on the Canadian case, it is “likely” that mad cow disease is also present in the United States. Now that mad cow disease has been found in a downer cow in North America, is the USDA drafting plans to at least step up its surveillance of downer cattle? According to a spokesperson for the USDA, “at the moment, no changes [in the US testing program] are being discussed.”

3. Stop feeding bovine brains, eyes, spinal cords or intestines to people or livestock.

The third key recommendation of the World Health Organization is that, “Countries should not permit tissues that are likely to contain the BSE agent to enter any food chain, human or animal.” Basically, this means excluding cattle brains, eyes, spinal cord and intestine (from small intestine to rectum) from the human food supply, and from all animal feed. Unfortunately, the US still feeds those potentially risky tissues to people, pigs, pets and poultry.

After a cow is slaughtered and the standard cuts of beef removed, one is left with a bloody skeleton with a few scraps of meat still attached. To recover any last shreds of meat, the bones, prebroken or whole, may be placed in a giant vise-like device that crushes the carcass into bone “cakes.” Out through a sieve at the bottom runs a “batter-like” paste of “spread-like consistency” referred to as mechanically separated meat. The potentially highly infectious spinal cord and fluid may be forced out of the backbone and spewed into the final product. Mechanically separated beef has been “used as a meat ingredient in the formulation of quality meat food products” in the United States since the 1970’s. Examples of such “quality meat food products” include hot dogs, sausages and burgers. By law, hot dogs can contain up to 20% of this mechanically separated beef.

Although food containing mechanically separated beef must be labeled as such, there are no labels on food in restaurants. So people could be exposed to spinal cord tissue in hot dogs, sausages, hamburgers, and ground meat products when dining out.

In 1994, meat processors began using a new technology, called advanced meat recovery (AMR), to help “increase yields and profitability.” These systems also extrude meat from the remains of the carcass under pressure, but without crushing the bones.

The end-product varies from a ground beef-like texture to the consistency of thick tomato sauce. Prior to 1994, only cattle skeletal muscle, tongue, diaphragm, heart, and esophagus could be labeled as beef. But by the end of that year, the USDA had already amended the definition of “meat” to include the product of advanced meat recovery machinery. This meant that, unlike mechanically separated meat, AMR meat was considered 100% beef and could be labeled as such. With no special labeling requirements, adoption of AMR machinery spread rapidly throughout the industry, largely replacing mechanical separation equipment.

Today, the majority of cattle are now processed using AMR. Over twenty thousand tons of AMR beef is produced every year in the US, valued at over $100 million. AMR beef typically ends up as a hidden ingredient in hamburgers, hot dogs, sausages, and beef jerky, as well as part of ground beef in meatballs, pizza toppings and taco fillings.

…the US still feeds those potentially risky tissues to people, pigs, pets and poultry.

Companies are supposed to remove the animals’ brains and spinal cords before processing the carcasses through the AMR machinery, but getting out all of the spinal cord can be challenging. “It requires special tools and skills,” says Glenn Schmidt, a meat scientist at Colorado State University. “The workers have to reach down to the neck region of the carcass to remove the spinal cord by scraping or suction, and sometimes they don’t get all of it.”

The first major study of AMR meat was published in 2001. Colorado State University researchers found that “well over 50%” of the samples of AMR beef from neck bones were contaminated with CNS tissue. Then they went to seven major suppliers of large fast food chains across the country to sample hamburger patties. Six out of seven suppliers had detectable CNS tissue in their burgers.

The USDA again responded only with promises to do more testing. The results of the USDA’s tests were made public in 2002. Eighty-eight percent of the meat processors (30 out of 34) were producing AMR beef which contained unacceptable nervous tissue, and almost all of the samples (96.5%) contained bone marrow, which may also be infectious.

…stunners currently in use in the US today may still force brain into the bloodstream of some of these animals.

The consumer advocacy group Center for Science in the Public Interest (CSPI) petitioned the USDA to require processors to remove the entire spinal column before sending carcasses through the machinery. The petition was opposed by the National Cattlemen’s Beef Association, the National Renderers Association, the National Meat Association, the Pork Producers Council, the sheep industry, the milk producers, the Turkey Federation, and eight other industry trade groups.

The meat industry has invested at least $40 million in AMR machines since their introduction in 1994, some of which can process 9,000 lbs. of bones per hour. Industry analysts place the final figure of complying with any proposed USDA regulation that bans neck bones and backbones at close to $200 million dollars.

Even boneless cuts may not be risk-free, though. In the slaughterhouse, the bovine carcass is typically split in half down the middle with a band saw, sawing right through the spinal column.

This has been shown to aerosolize the spinal cord and contaminate the surrounding meat. A study in Europe found contamination with spinal cord material on 100% of the split carcasses examined. Except for Islamic halal and Jewish kosher slaughter (which involve slitting the cow’s throat while the animal is still conscious), cattle slaughtered in the United States are first stunned unconscious with an impact to the head before being bled to death. Medical science has known for over 60 years that people suffering head trauma can end up with bits of brain embolized into their bloodstream; so Texas A&M researchers wondered if fragments of brain could be found within the bodies of cattle stunned for slaughter. They checked and reportedly exclaimed, “Oh, boy, did we find it.” They even found a 14 cm piece of brain in one cow’s lung. They concluded, “It is likely that prion proteins are found throughout the bodies of animals stunned for slaughter.”

The Texas A&M study was published in 1996 using the prevailing method at the time, pneumatic-powered air injection stunning. The stunning devices that remain in widespread use drive similar bolts through the skull of the animal, but without air injection. Operators then may or may not pith the animals by sticking a rod into the stun hole to further agitate the deeper brain structures to reduce or eliminate reflex kicking during shackling of the hind limbs. Even without pithing, which has been shown to be risky, these stunners currently in use in the US today may still force brain into the bloodstream of some of these animals.

In one experiment, for example, researchers applied a marker onto the stunner bolt. The marker was later detected within the muscle meat of the stunned animal. Even non-penetrative “mushroom-headed” stunners which just rely on concussive force to the skull to render the animal unconscious may not be risk free. The researchers at Texas A&M conclude, “Reason dictates that any method of stunning to the head will result in the likelihood of brain emboli in the lungs or, indeed, other parts of the body.”

The National Cattlemen’s Beef Association continues to assure consumers that beef is safe because the deadly prions aren’t found in muscle meat. In 2002, Stanley Prusiner, the Nobel laureate who discovered prions, proved in mice, at least, that muscle cells themselves were capable of forming prions. He describes the levels of prions in muscle as “quite high,” and describes the studies relied upon by the Cattlemen’s Association as “extraordinarily inadequate.” Follow-up studies in Germany published in May, 2003, confirm Prusiner’s findings, showing that an animal that is orally infected may indeed end up with prions contaminating muscles throughout the body.

…an animal that is orally infected may indeed end up with prions contaminating muscles throughout the body.

The surprising new finding linking mad cow disease with classic CJD has been used to explain the rising numbers of those stricken with the classic form of CJD in Europe. We don’t see the incidence of this fatal disease in North America because the disease isn’t tracked here like it is in Europe. We do know, though, that when researchers have actually gone back and looked at the brains of presumed Alzheimer’s deaths—where Alzheimer’s was indicated on the death certificate—anywhere from 3% to 25% had actually died of Creutzfeldt Jakob Disease. According to the CDC, Alzheimer’s Disease is now the eighth leading cause of death in the United States, affecting as many as 4 million Americans. Despite the fact that an unknown number of Americans are already dying from this disease, the beef industry continues to ignore the evidence.

In another direct violation of the World Health Organization’s recommendations and international standards, the tissues with the highest potential for risk, cattle brains and spinal cord, are rendered directly into animal feed that continues to be fed legally to pigs and chickens in North America.

In the United States, slaughterhouse waste from cattle is rendered, or melted down, into “meat and bone meal” which is used in animal feed to help “animals grow bigger and faster.” Over 18 million pounds of meat and bone meal are produced every day in the United States.

…cattle remains can be fed to chickens, and then the poultry litter can be fed back to cows.

Almost all fattening beef cattle, all dairy calves and all adult dairy cows raised conventionally are fed meat and bone meal in the United States. In fact, conventional dairy cows eat about a pound of meat and bone every day in North America. Since the partial 1997 FDA feed ban, however, this meat and bone meal is not supposed to come from ruminants (other cattle, sheep or deer).

Unfortunately, these regulations have been poorly enforced. In 2001, the Food and Drug Administration published the results of a national survey of rendering plants and feed mills. Up to a quarter of the plants were found in violation of the 1997 feed regulations, years after the so-called ban went into effect.

Ruminant meat and bone meal, even derived from downer cattle too sick to walk or stand, can still be sold in North America. As pointed out by Dr. Michael Hansen from the Consumers Union, “All they said is that you’ve got to label it.”

Even with 100% compliance with the feed regulations, however, cattle remains are still legally fed to pigs, for example, which have been found to be susceptible to BSE prions. Then the pig remains can be fed back to cattle. Or cattle remains can be fed to chickens, and then the poultry litter can be fed back to cows. In these ways, prions may be indirectly cycled back into cattle feed.

The beef industry argues that this practice is safe because poultry litter is processed to eliminate pathogens before being fed to cattle. This typically involves heating the litter to about 140 degrees Fahrenheit, which is less than your typical sauna.

The reason the industry may be so recalcitrant is that approximately 60% of the meat and bone meal produced in the United States is of ruminant origin. But as far back as 1993, Gary Weber, a spokesperson for the National Cattlemen’s Beef Association, admitted that the industry could indeed find economically feasible alternatives to feeding rendered animal protein to other animals, but that the Cattlemen’s Association did not want to set a precedent of being ruled by “activists.”

4. Stop weaning calves on cow’s blood.

The last key recommendation of the World Health Organization was that, “All countries should ban the use of ruminant tissues in ruminant feed.” The USDA boasts, “To stop the way the [mad cow] disease is thought to spread, in 1997, FDA prohibited the use of most mammalian protein in the manufacture of animal feed intended for cows and other ruminants,” the pivotal word being “most.”

Like all mammals, cows can only produce milk after they’ve had a baby. And most newborn calves in the United States are separated from their mothers within 12 hours—many immediately after birth—so that the mother’s milk can be marketed for human consumption. Though many dairy farmers still wean their calves on whole milk, the majority of dairy producers use milk replacer, which is basically a blend of water with a source of protein and some source of fat, as a cheaper alternative to milk. Outbreaks of mad cow disease in Denmark, Germany and Japan have already been tentatively tied to milk replacer which used beef tallow as a source of fat.

The protein source in milk replacer is most often milk protein (whey), but dairy farmers also suckle their calves with milk replacer made from cattle blood protein. The number one advantage given for using blood as a protein source in milk replacer is that it is cheaper than whey.

The medical director for the US Public Health Service reviewed the blood infectivity literature and found 15 published studies showing prion transmission through blood. A sixteenth study, published in 2002, showed that blood taken even from an asymptomatic animal that was silently incubating BSE could still transmit the infection via a blood transfusion.

In 2002, the USDA requested feedback on a number of options for further preventive measures, including a total ban on allowing the brains and spinal cords from downer cattle in the human food supply. The spokesperson for the American Meat Institute explained that the meatpacking industry would take a “significant hit” financially if the USDA enacted such a proposal.

The American Meat Institute replied, “No, BSE is a foreign animal disease.” They stressed that, “The fact that we share no physical borders with any affected nations has been a key means of protecting our cattle.”

Now that mad cow disease has been discovered in North America, the USDA should immediately enact measures to prevent human exposure by issuing an emergency interim rule to ban products that may contain the agent that causes mad cow disease. So far, though, according to an agency spokesperson, the USDA isn’t even discussing plans to increase testing for the disease.

David Byrne, the European Commissioner for Health and Consumer Protection, said, “One of the major lessons I have learned in dealing with BSE is that the political establishment must be fully transparent with the public on the issue. There must be no hidden agendas. No distortions. No false assurances. Transparency, information and open dialogue must guide our actions.” The United States could learn from Europe’s experience.

An unabbreviated version of this report is available on the Organic Consumers Association Mad Cow news page: http://www.organicconsumers.org/madcow.htm. The report itself is here: http://www.organicconsumers.org/madcow/GregerBSE.cfm

Any part of this report may be reproduced subject to acknowledgment.

Michael Greger, MD, is a graduate of the Cornell University School of Agriculture and the Tufts University School of Medicine. Dr. Greger has been publicly speaking about mad cow disease since 1993. In 1997 he was invited as an expert witness to defend Oprah Winfrey in the infamous meat defamation trial. He has contributed to many books and articles on the subject and continues to lecture extensively. Dr. Greger can be contacted at 857-928-2778, or mhg1@cornell.edu

[23 dec 03]

Synthesis/Regeneration home page | s/r 33 Contents