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Beefing Up Food Safety
Dave McSwane offers some rare insights.
 Is “mad cow disease” going to be a threat
in the U.S. anytime soon?
I really don’t think so. The USDA and other organizations
are creating a system that will assure protection of our food
supply against Bovine Spongiform Ecephalopathy (BSE) or what is
commonly referred to as “mad cow disease.” There is
a disease similar to BSE called Creutzfeldt-Jacob Disease (CJD)
found in humans, and a variant form of CJD (vCJD) is believed
to be caused by eating contaminated beef products from BSE-affected
cattle. According to the FDA, there have been 155 confirmed or
probable cases of vCJD worldwide. To date, we’ve identified
only two cows in the U.S. with BSE.
The public’s perception of risk is attributed at least in
part to the media coverage of this issue, but there are other
food safety issues that should be more on their minds than mad
cow at this point. I do think that the USDA has certainly taken
the necessary steps to enhance their regulatory oversight with
the tracking of animals and safeguards that should, with a high
degree of effectiveness, protect Americans from mad cow disease.
Should we be worried about food coming from areas affected
by the recent hurricanes?
Probably not, mainly because there isn’t much food coming
out of those regions due to the devastation. The more fundamental
issue is that we do have safeguards in place to ensure the safety
of the American food supply. The real key is to always buy food
from approved sources. These would be sources that are routinely
inspected and under the jurisdiction of either a federal or state
food or public health agency. The bottom line is if you buy your
food from approved sources, you should be able to minimize your
risk significantly.
So what should we be worried about?
There are many other pathogens that we need to be concerned about.
In terms of causing disease, there are things like the E. coli
organism that can cause a variety of symptoms and in some cases,
very severe health problems for children. Listeria monocytogenes
is another pathogen that has emerged on the scene in the last
few years that is dangerous for children and in some cases, has
been shown to cause stillbirths when it’s consumed by pregnant
women.
Historically, food scientists and public health professionals
have considered pathogenic bacteria as the most common cause of
food-borne illness. This is largely due to the fact that it’s
easier to isolate and study these bacteria. However, in recent
years we have improved our techniques for detecting and studying
viruses. We now believe viruses such as hepatitis A and noroviruses
are as important, and in many cases more important, than bacteria
as causes of food-borne illness.
Norovirus outbreaks have only started to get attention after their
impact on cruise ships in the past few years.
In many instances, food employees may be infected with hepatitis
A or norovirus and not show symptoms and can be shedding viruses
without even knowing they’re sick. Another significant fact
is that it usually takes only a small number of virus particles
to make a person sick. Where it may take hundreds or thousands
of bacterial cells to make a person ill, it would take less than
ten virus particles to cause disease.
What do you think the FDA and USDA are really doing
well right now?
The new approach taken by both of these organizations is to ensure
food safety throughout the entire food chain. We start at the
farm by implementing good agricultural practices to minimize contamination
of our food supply. Certain things can be done at the farm that
can help to reduce the prominence of pathogens. From there, we
have good manufacturing practices, which are designed to take
a product that is as safe as it can be from the farm and make
it safer, whether it’s by processes like irradiation or
pasteurization or by having surface contaminants removed prior
to going to retail. At retail, our emphasis is once again on making
sure the products we have purchased are safe and kept in that
condition and that we’re not doing anything in terms of
handling in supermarkets and restaurants that would result in
a recontamination of the food.
In those cases where a product like raw meat or poultry is likely
to have bacteria, we need to make sure we are cooking the food
properly and following the steps to ensure those disease-causing
organisms are reduced to a safe level before eating the food.
What food safety issues aren’t being addressed
by the FDA and USDA but should be?
I don’t know that there are any issues that are not being
addressed. In some cases it’s just that our system is in
need of upgrading because most of the pathogens that we’re
dealing with are microorganisms. Historically, the food safety
system has pretty much been based on the sensory evaluation of
products—in other words, how does the food look, feel, or
smell? Because most of the common causes of food-borne illness
are microorganisms, you can’t detect a problem unless the
product is spoiled or extensively damaged. A visual-based inspection
program is not 100-percent foolproof in protecting against these
microbial pathogens. Current improvements are in what we call
“real-time detection,” where scientists are developing
tests for these microbes so we can take samples from the surfaces
of carcasses and other foods and provide prompt results. In this
way, contaminated products can be prevented from entering the
food chain.
Federal agencies are looking into how to protect the
food supply from terrorists. How can terrorists attack our food
supply and what is needed to protect it?
Certain viruses could be spread or botulism may be used. The real
key is that we do have a global food supply and a vast majority
of the products we eat in the U.S. come from outside sources and
it’s difficult to maintain control. But the USDA and FDA
are typically trying to maintain an effective system for monitoring
those products. One of the things on the horizon is country-of-origin
labeling so we can track these products.
Would this be more of a threat from imported food?
Wouldn’t have to be. One of the first cases of terrorism
came from a domestic situation in which a group was trying to
disrupt a local election and contaminated food on a salad bar
with salmonella bacteria. But the chance to have a sizable effect
on the health of people would not be nearly as great using food
with a biological agent as it would be if you used smallpox with
its rapid person-to-person spread. You could make a small group
of people sick, which would attract media attention and might
raise the level of fear. If that’s the terrorists’
objective, they can achieve that, but if a terrorist wants to
have a catastrophic effect, there are probably more effective
approaches than using our food supply.
Why are people worried about genetically engineered
fruits and vegetables?
It’s probably as much of a lack of consumer education as
anything. In the opinion of the food science community, the health
risk associated with eating a genetically modified organism (GMO)
is pretty small. There may be a very, very minor risk with people
with certain sensitivities or allergens, although I’m not
sure that it is any greater with genetically modified organisms
than it would be with any other product that might contain allergens.
We’ve used genetically modified organisms in the United
States for decades now and have not seen any major problems. I
think if there is a concern for GMOs, it may be more of an environmental
impact than a health impact.
What are the food safety issues in the typical kitchen?
We have seen certain kinds of meat products like hot dogs and
bologna linked to Listeria monocytogenes and in practically all
cases, the risk of contracting a food-borne illness is going to
be highest among the most susceptible populations: the very young,
the elderly, people with some sort of an immune deficiency, and
pregnant and lactating women, because they run the risk of passing
the pathogen to their child. Things like poultry should be cooked
well because there’s salmonella and other bacteria that
are pretty much just inherent. Same with ground beef.
The other thing I’m concerned about in kitchens is cross-contamination.
People will cut raw poultry on a cutting board and then, without
cleaning and sanitizing the board, the knife, or their hands,
they chop up the ingredients for a salad. So now you’ve
got bacteria transferred from the raw chicken to a salad that
won’t be cooked and you won’t get the thermal destruction
of the bacteria. Preventing cross-contamination, good personal
hygiene—especially hand-washing, and proper sanitation of
cutting boards and counter tops—are things that consumers
should think about.
How about alfalfa sprouts?
Some people at the top level of the food science community say
sprouts, by their very nature, are probably the most high-risk
food a person can eat. In many cases, the pathogens are actually
in the seed and unless they are disinfected in some way, that’s
a problem. In some cases, depending on the way they were produced,
they might be healthy, but I think it’s sort of like the
raw oysters. If you choose to eat them, you definitely are raising
your risk.
Overall, do you think our food system is safe and being
regulated properly?
It’s not to say we don’t have food-borne illness,
but if you look at the number of meals served and the amount of
food produced and sold in this country, people have a relatively
low risk and they should not be alarmed in any way. Our food safety
system works and it’s being improved all the time. But the
last line of defense is really the consumer, and they should view
themselves in that role because ultimately they can do things
to protect or endanger themselves or their families.
David
McSwane
is an associate professor at the School of Public and Environmental
Affairs, IUPUI. His expertise is in food safety, drinking water
safety, and the health effects on environmental hazards. He is
teaching courses on environmental health policy and food science
and sanitation.
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