http://www.latimes.com/news/nation/20010220/t000015331.html
'Mad Cow' Risk in U.S. Tiny but Real, Experts Say
Health: Regulators believe that Americans are safe. However, gaps in food
quality rules are raising questions.
By MELINDA FULMER, Times Staff Writer
�����Gaps in U.S. food safety regulations and enforcement and the dearth of
information about how "mad cow" disease spreads have raised questions over
whether American consumers really are insulated from the disease that has
caused the deaths of 94 people across Europe.
�����While country after country in Europe has fallen prey to Britain's mad
cow epidemic, U.S. regulators have stood firm on their assurances that
Americans are safe, citing import bans, animal testing, curbs on blood
donations and feed restrictions.
�����Although no cases of bovine spongiform encephalopathy have yet been
reported in the United States, and experts claim it is "highly unlikely" that
BSE will become a problem here, the same experts concede that it is
impossible to rule it out.
�����"I don't think that any country can say they are 100% sure that they are
free of BSE," says Ralph Blanchfield of the independent Institute of Food
Science and Technology based in Britain.
�����"I think it's reasonable that people are worried," says Stephen
DeArmond, a UC San Francisco neuropathologist who collaborated on the 1997
Nobel Prize-winning research on the agent that causes BSE.
�����Many food safety advocates are wary of government assurances in the wake
of the recent StarLink fiasco, in which a genetically modified animal feed
corn not approved for human consumption wound up in everything from taco
shells to corn chips.
�����Though the risks of a mad cow outbreak in the U.S. may be slim, there
are concerns about gaps in these areas:
�����* Feed mills. If BSE does exist undiagnosed somewhere in the nation's
cattle or dairy herds, there's a chance that it could be spread by mix-ups at
feed mills, some of which have been lax in following regulations aimed at
stopping BSE. The disease was spread in Europe through contaminated animal
feed.
�����* Imports. American companies imported feed from Britain made of
rendered animals for three years after BSE was diagnosed there in 1986.
Moreover, over the past decade, 32 cows were shipped in from Britain that
U.S. Department of Agriculture officials can't account for.
�����* Inadequate testing. Although 12,000 so-called downer cattle, or cattle
that could not walk on their own when they were brought in for slaughter,
were destroyed in the U.S. this decade and their brains tested for BSE, some
industry observers believe that is not enough to guarantee that U.S. herds
are free of the disease. There is no test that can detect the disease in live
animals.
�����* Related diseases. Sheep, deer, elk and mink in this country have
contracted diseases in the same family as BSE known as transmissible
spongiform encephalopathies, or TSEs, which are not fully understood and
carry some of the same neurological symptoms.
�����BSE affects the central nervous system of cattle and is known to cause a
human version called new variant Creutzfeldt-Jakob disease, which bores holes
into the brain, causing bodily dysfunction, dementia, hallucinations and
death.
�����Worldwide there have been about 178,000 cows identified with the disease
since it was diagnosed in Britain 15 years ago. The disease has spread from
Britain to native-born cattle in other European countries, such as France,
Italy, Switzerland, Germany, Portugal, Ireland and Spain, through
contaminated feed and been exported to areas such as the Falkland Islands and
Canada.
�����It is believed to be spread by a mysterious particle called a prion, an
infectious molecule in the membranes of cells that is neither a bacterium nor
a virus and is largely found in the brain and spinal cord of an infected
animal.
�����If BSE does exist undetected in this country's herds, the biggest threat
to the food chain would come from lax practices at feed mills.
�����U.S. regulators have barred mills from selling cattle feed made from
meat and bone meal from BSE-susceptible animals since 1997.
�����However, rendered dairy cows, sheep and goats are still used in feed for
pigs, a point that concerns some scientists, who fear that the disease could
spread to other species. They say the practice leaves the door wide open for
mix-ups such as the one at Purina Mills in Gonzalez, Texas.
�����There, the company acknowledged selling cattle ranchers feed made from
rendered cows, prompting a quarantine of 1,222 cattle. The animals, which
were bought and taken out of the food chain by Purina, are not believed to
have been infected with BSE.
�����However, the incident highlighted how easily a contamination could start
and raised questions about the Food and Drug Administration's ability to
effectively police the food chain.
�����It was cross-contamination like this that played a part in how the
genetically modified and potentially allergenic feed corn called StarLink
made its way into the food supply last year.
�����To ensure that it was operating at "zero-risk," Purina vowed to stop
mixing meat and bone meal into all of its animal feeds.
�����However, some of the nation's largest feed companies, such as Land
O'Lakes Farmland Feed and Cargill, still use meat and bone meal in feeds for
animals other than cows.
�����And not all of them are using it responsibly, according to a report
issued last month by the FDA. In its inspections of more than 1,000 U.S. feed
mills, the FDA found that 20% did not have the proper precautionary
statements on their labels. And 9% did not have a system in place to prevent
commingling of cattle feed with feed meant for other animals. The report did
not identify the violators.
�����Five recalls have been issued for improperly labeled feed since the 1997
ban, the FDA said.
�����There are probably many more companies not in compliance. The FDA has
not yet finished its first inspection of all of the nation's feed mills and
renderers. It has no system in place for regular inspections or sampling,
says Stephen Sundlof, director of the FDA's Center for Veterinary Medicine.
�����Critics say the agency will also need to take a tougher stance on
enforcement to keep companies honest. Currently, offenders of the ban are
given an oral warning and a letter asking for a recall before any product is
subject to seizure.
�����"It doesn't do any good to have regulations if you have no enforcement,"
says Mark Ritchie, director of the Minnesota-based agricultural think tank
Institute for Agriculture and Trade Policy. "These companies should be
[temporarily] shut down if they are violating the rules."
�����Some food safety experts insist that because USDA officials acted early
to restrict imports and close in on potential problems, current regulations
should be sufficient to protect consumers and prevent the spread of the
disease.
�����The U.S. has had a ban on live animals imported from Britain since 1989
and on animals, meat, bone meal and other products from affected European
countries since 1997.
�����However, because some animal products were shipped over after animals
were diagnosed in Britain, the risk of BSE existing here cannot be ruled out,
Blanchfield says. "The U.S. imported just under [44,000 pounds of British
feed] in 1989, when the epidemic started to get going but was not at its
peak."
�����In addition to feed, the USDA keeps tabs on more than two dozen cattle
that were shipped in from Europe during the past decade and still live on
farms in Texas, Minnesota, Illinois and Vermont, says the USDA's head
veterinarian and mad cow expert, Linda Detwiler.
�����So far, none has exhibited symptoms of BSE, and they are believed to be
too old to harbor the disease.
�����However, some observers worry about the 32 cows shipped in from Britain
during the past decade that USDA officials still can't account for.
�����Academics say the risk to this nation's 98 million head of cattle from
fewer than three dozen animals is too low to even calculate. "The risks of
having a U.K.-like [situation] are infinitesimally small" because of the feed
ban, says George Gray, researcher at the Harvard Center for Risk Analysis,
which has studied the subject for two years.
�����It was the continued sale of feed made from the meat and bone meal of
contaminated animals that was responsible for BSE's rapid spread across
Europe, and that practice was promptly stopped in the United States.
�����Still, skepticism is understandable, scientists say, given how much is
not yet known about the disease. "We don't have the tests yet to verify that
there is no problem [in our herds]," says DeArmond of UC San Francisco.
�����A number of companies are rushing to come out with a blood test that
will detect the disease in live animals. Currently, the disease is diagnosed
only by studying brain tissue after an animal dies or is killed.
�����During the past decade, the brains of 12,000 so-called downer cattle
have been tested, and all tests have been negative, Detwiler says.
�����Contributing to the confusion and fear is the host of similar diseases
affecting other animals in this country, such as deer, elk, sheep and mink.
�����Although these diseases have not been shown to jump species, scientists
can't say they haven't. And the experts can't fully explain how the animals
developed the cell abnormality to begin with.
�����Two hunters in this country who ate deer and elk, and one non-hunter who
ate venison, have died from Creutzfeldt-Jakob disease, Detwiler says. There
was no direct link established, however, because it is not known whether they
ate animals infected with TSE.
�����Ritchie, the think tank director, argues that there hasn't been enough
education for hunters and additional precautions taken to protect consumers.
�����"Why government hasn't acted on what it's known is a very big question,"
he says. "This is a direct threat, and it's not being dealt with."
�����So far, cases of so-called mad deer disease have been identified in wild
animals in Colorado, Wyoming and Nebraska, and on 13 elk farms in those
states plus Montana, South Dakota, Oklahoma and Saskatchewan, Canada.
�����Regulators won their fight to wipe out the threat from the sheep version
of BSE, also known as scrapie, which was found in four animals on a Vermont
dairy farm.
�����A federal judge ruled that the USDA can seize and destroy these animals
along with a second flock also imported from Belgium that may have eaten
contaminated feed.
�����Scrapie-infected sheep ground up in feed are thought to be the initial
cause of BSE in Britain. So far, scrapie does not appear to affect humans
when ingested.
�����Experts say consumers would have to feast on the brains and backbones of
cows to stand a significant risk of exposure to BSE.
�����The prions causing BSE aren't found in muscle. There is also no evidence
that milk or blood pass on the disease.
�����"I probably wouldn't worry too much about eating beef in the U.K.," says
Dean Cliver, a food safety professor at UC Davis. "And I certainly wouldn't
worry about it here."
* * *
�����Reuters contributed to this report.
