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Ottawa Station: CBO-FM
20 January 2000
Genetically Engineered Foods
ANTHONY GERMAINE (CBO-FM): A group of Canadians is looking to step up
the debate over genetically engineered foods. The group is made up of
scientists, academics, and farmers, and they call themselves G.E. Alert.
Ann Clark is one of the members. She's also an Associate Professor of
Plant Agriculture at the University of Guelph. Dr. Clark just published
a review of the way that genetically engineered foods are tested by Health
Canada, and she says the tests simply are not good enough. We reached
Dr. Clark in Wooster, Ohio, where she's working on sabbatical. Good morning.
ANN CLARK (Member, G. E. Alert): Good morning to you.
GERMAINE: Now Dr. Clark, what exactly did you examine when you set out
to analyse the way Health Canada tests genetically engineered crops?
CLARK: Well, we did something that I would really encourage your listeners
to
do, and that was go to the website for Health Canada where they have posted
the decisions for each of the 42 genetically engineered crops which have
been
approved for use in Canada. And we looked specifically at how... let's
put it
this way, what information Health Canada regulators accepted from industry
to
indicate lack of risk of toxicity and allergenicity.
GERMAINE: Okay. Toxicity and allergenicity?
CLARK: Right.
GERMAINE: You better explain those.
CLARK: Well, some toxins, something that would be toxic to health, or
something that would be a... create allergic responses.
GERMAINE: Right. And what did you find?
CLARK: Well, it was interesting and surprising. We found that, contrary
to
what industry has said all along, and what government regulators have
said all
along, seventy percent of the crops that have been approved were approved
based on no laboratory or feeding trial tests for toxicity, and 100 percent
of the
approved crops had no feeding trial or laboratory tests for allergenicity
at
all.
GERMAINE: So I just want to get this straight; you're telling me that
two-thirds of the crops that have been approved weren't tested for toxicity
and none of them were tested for their allergenic potential?
CLARK: That's right. The conclusion of safety, based on toxicity and
allergenicity for those crops was based entirely on inferences drawn from
assumptions that we in G.E. Alert considered to be unfounded assumptions.
GERMAINE: Well, when you talk about inferences that were drawn from unfounded
assumptions can you be a little more explicit? What does that mean?
CLARK: Sure. The central premise of the risk assessment system in Canada
is
that when you insert a transgene, any kind of a gene, into a new host,
for
example the gene for Round Up resistance, into a soybean, the only thing
that
is affected is the trait that you're inserting. In other words, you're
conferring Round Up resistance to that soybean.
GERMAINE: What's Round Up resistance?
CLARK: Round Up is an herbicide. It's a very commonly used herbicide,
and the advantage to this from a commercial point of view is you can then
spray Round Up on a growing field, a field that has soybeans in it, and
it kills
everything except the soybean. So it's a vehicle for simplifying weed
control.
GERMAINE: Okay, so you make the plant resistant to it so you can just
spray
like crazy.
CLARK: Well, I'm sure they don't spray like crazy because it costs money,
but
that's the idea, and it's something you couldn't do before because Round
Up is
a broad-spectrum herbicide and it would have killed the soybean. So it's...
that's the logic behind the use of it. But what has actually happened
is that
when you insert a transgene you actually affect other traits, things that
have
no relationship at all to Round Up resistance. And this is a process problem.
It results because of the process of the insertion of the transgene itself,
which is done randomly. The transgene doesn't go into the same place each
time;
you don't know on which chromosome it's gonna go, you don't know where
it's
gonna go on the chromosome. And the order that it goes in makes a
difference in other traits. So completely unrelated traits can be affected.
GERMAINE: So just to be totally clear here, once you insert this transgene...
you have an objective in mind in this instance with the soybean, to make
it
resistant to a pesticide...
CLARK: That's right.
GERMAINE: ... you don't really know what other aspects of the plant that...
that are going to be affected. Is that right?
CLARK: That's correct. And you don't know unless you look. And the system
that is used to assess in Canada is based entirely on the target gene
and the
single protein that is coded for by that target gene, and that's all that
is tested.
So, for example, on 30 percent of the crops, they actually do test for
toxicity, they do laboratory tests, and they do feeding trial tests. But
they
don't feed the whole grain, or the whole potato. What they do is they
purify a
single protein, so a single purified protein is what is tested in a lab
and
what is fed to rats to test for acute toxicity. This is a very different
thing
than feeding the entire grain, in which these other side effects, potential
side effects, could be detected. So by the protocol that's used using
only
purified proteins, really avoids the whole issue of secondary side effects.
This is not a theoretical issue, and this is not something that is necessarily
going to be caught before the product gets to market.
A case in point is Round Up Ready Soybeans which were grown in Georgia
for the last two years. Now the farmers growing this crop noticed that
the stems on
the soybean plants were splitting when the spring soils were very hot,
which was
unusual for them, and this happened only with Round Up Ready Soybeans.
The
original cultivar that the Round Up resistant gene was put in, this didn't
happen.
GERMAINE: The cultivar?
CLARK: The original variety that the transgene was put into.
GERMAINE: Right.
CLARK: So you have an existing variety, and you insert this transgene.
The
existing variety didn't have the problem, but the transgenic variety did.
GERMAINE: So the ones that they'd altered genetically were splitting.
CLARK: That's right. And what happened then was the fungus... fungal pathogens
invade the split and it dropped their yields by about 40 percent. So they
took this concern to researchers at the University of Georgia and they
looked into it and confirmed that in fact it was an interaction between
the transgenic plant and the hot soils that caused this to happen. It
doesn't happen in cool soils and it didn't happen with any other cultivar.
In the other transgenic
cultivar it didn't happen.
GERMAINE: So if I understand what you're saying the genetic alteration
meant
that they had fewer successful plants.
CLARK: It... well, what it essentially did is it affected traits other
than
the intended traits. And in this particular case it was a very obvious
trait, the
stems were splitting. And what we in G.E. Alert are suggesting is that
many
things could be affected and you will never know if you don't look for
them.
And we don't look for them in the risk assessment system that's used for
either food safety or environmental risk in Canada. And keep in mind this
problem with the soybeans, this escaped detection from the proprietors,
the owners of the Round Up Ready Soybeans, and the regulators. They both
missed it and it got out into commerce, and it has affected yields in
soybeans in commerce.
GERMAINE: Okay. You spent a fair time on this Round Up Ready Soybean example.
What's the lesson there?
CLARK: Well, the lesson is that when you insert a transgene more than
one
thing is affected, and so you have to look for that. You have to test
for other
things. And we're not testing. That's the criticism.
GERMAINE: So what is it that Health Canada should be doing differently?
CLARK: Well, what I would suggest, because this is not my field, I'm a
pasture
scientist, is they should go to the professional associations, the
professional societies of entomologists or toxicologists or whatever it
might be, and ask them to respond. What are the issues that you think
should be considered in a risk assessment protocol? And how would you
assess it? And I would go back to the professionals who were experts in
the field who have not been consulted in developing this technology and
get their opinion. That's how I would do it.
GERMAINE: Now, finally, do we as consumers have anything at our disposal,
anything at our means that we can do to actually put some pressure on
Health
Canada? What would you suggest that we as consumers of food do about this?
CLARK: Well, you're getting a little out of my expertise 'cause we're
all
scientists and we're really just interested in insuring that the decisions
that are made on genetically engineered food in Canada are based on sound
science, and clearly they're not in this case. How consumers choose to
take that
information and use it is really to their discretion. But I think... I
think
there are many options that are available to them, and I guess I don't
need to
advise them how to do that.
GERMAINE: Okay. Well thank you very much.
CLARK: I thank you.
GERMAINE: Okay, bye now.
CLARK: Bye bye.
GERMAINE: Dr. Ann Clark is an Associate Professor of plant agriculture
at the
University of Guelph and a member of G.E. Alert -- it's a group of scientists,
academics and farmers who are hoping to fuel a debate over genetically
engineered foods.
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