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August 24, 2000


Monarchs and Bt study


Steve Milloy has a great take on the media spin of the Monarch study from
Iowa state. Especially notable is his perspective on how reporters appear
to be selectively reporting "bad" news when they are fully aware of other,
more favorable and more exhaustive research. The mass media has a major
impact on the public's view of biotech and this is a great example of why.
A more interesting question is: Is it innocent, ignorant, or intentional?

LINK: http://www.foxnews.com/science/junkscience/index.sml

Date: Aug 25 2000 07:57:35 EDT
From: Steven Milloy
Subject: Butterfly 'Survivor'

My column on the new Bt corn-Monarch butterfly study, "Butterfly
'Survivor'" is at http://www.foxnews.com/science/junkscience/index.sml.

Steve Milloy

Butterfly Survivor
August 25, 2000
By Steven Milloy

It's been a big week for CBS television. Not only did the network air the
grand finale of the popular Survivor, but CBS News broke news about the
Monarch butterfly edition of Survivor.
The subject: How many butterflies will survive when plucked from their
natural environment and forced to live on a toxic island?

"It is the first field study to show that America's favorite insect, the
monarch butterfly, can die from the pollen of gene-altered corn," reported
CBS News' Wyatt Andrews about a new study out of Iowa State University.

But Andrews overreacted. The new study is as much a "field study" - and as
realistic - as Survivor. The alarm over biotech corn and Monarch
butterflies started last year when Cornell University researchers reported
pollen from so-called "Bt corn" killed Monarch larvae under laboratory
conditions. Conditions that including forcing the Monarchs to eat toxic
pollen - or not eat at all.

Bt corn has been genetically modified to carry a protein toxic to the
European corn borer, a devastating pest. The protein is toxic to other
moths and butterflies, but they don't eat corn pollen. Before Bt corn was
approved, the Environmental Protection Agency concluded Monarch larvae
would have little exposure to the pollen.

Amidst last year's media hysteria - "Engineered Corn Kills Butterflies,
Study Says," was USA Today's headline - scientists said no evidence showed
Monarchs in the wild would ever consume harmful amounts of the pollen. In
the wake of that perspective and further research, the alarm subsided.

But since media sensationalism never goes out of style, the new study
easily resurrected the butterfly scare.
Iowa State University researchers - led by a graduate student - again
reported Bt corn pollen may be toxic to butterfly larvae. It's being
called a "field study," but there was very little "field work" involved.
The researchers put potted milkweed plants, the main food of Monarch
butterfly larvae, in and around Bt corn test plots. When Bt corn pollen
fell on the milkweed leaves, the researchers removed the leaves to a
laboratory where leaf sections about the size of a fingernail were placed
in lab dishes. The researchers put a Monarch larva on each tiny section.
Two days later, the researchers counted how many larvae died.
Some "field study." The larvae had no choice of food. They couldn't move
to clean leaf surfaces. Rain couldn't wash the pollen away. The
researchers placed the larvae on the top sides of the leaf sections when,
in the wild, the larvae would most likely be hatched on the underside,
away from pollen.

Even so, only 20 percent of the larvae died after two days.

Worse still, the Iowa State researchers used the type of Bt corn pollen
most toxic to Monarch larvae. Called "Event 176," it is about 50 times
more toxic than pollen from other Bt corn varieties. But it accounts only
for about 2 percent of the Bt corn market and is being phased out by its
producer, Novartis Seeds Inc. Scientists know from extensive research that
Monarch larvae and other beneficial insects can withstand much higher
doses of the pollen from the Bt corn that farmers usually plant.

Even so, the Iowa State researchers reported that beyond one meter from
the cornfield, no sample of Bt corn pollen, including from around Event
176 fields, exceeded the dose that could harm the Monarch larvae.

Not surprisingly, the media overlooked these key facts - and it's not the
first time.
Dr. Mark Sears of Canada's University of Guelph reported last February
that levels of Bt corn pollen measured at the edge of cornfields had no
effect on Monarch larvae. And Sears measured essentially no pollen five
meters away from cornfields. His study received almost no media attention.

There was scant coverage of this summer's University of Illinois field
study, which reported Bt corn pollen didn't harm black swallowtail
butterfly larvae placed on host plants in and around Bt cornfields.
Little attention was paid to a recent EPA report reviewing the safety of
Bt corn for non-target species. This report was so convincing that
Greenpeace withdrew its lawsuit challenging the EPA's approval of Bt corn.
The withdrawal, news by any standard, received no coverage.

There was some media coverage last November when 20 researchers from
several universities met near Chicago to present the results of actual
field studies of Monarch butterflies. None of those studies have been
published yet. The researchers want to collect two summers' worth of data
and will finish this summer. But at the meeting, heavily covered by the
media, the researchers presented preliminary data indicating Monarchs
aren't at risk from Bt corn, including:

The concentration of Bt corn pollen drops off very rapidly a short
distance from the cornfield.
The pollen concentration found on milkweed leaves near cornfields
generally isn't sufficient to harm Monarch larvae and other non-target
moths and butterflies.
Monarchs apparently don't like Bt corn pollen and avoid it when
Cornfields have very little milkweed.
Climatic conditions and other factors greatly reduce exposure to pollen
in the wild.

New York Times' reporter Carol Kaesuk Yoon covered the meeting, but still
reported this week, "Now, in the first study published on the subject
since the debate began, scientists from Iowa State University say plants
growing in and near the corn fields are being dusted with enough toxic
pollen to kill monarch caterpillars that feed on them."

She is technically correct by qualifying the study as "published." But did
Yoon simply forget the trip she made to cover the November meeting?

Also overlooked (ignored?) was Dr. Anthony Shelton, associate director of
research at Cornell University, who was very critical of the Cornell study
even though it was conducted at his own university. Shelton says the Iowa
State researchers make "conclusions that exceed their data and some of
their statements are simply off the mark."

"They do not provide any evidence that [a toxic] dose would be encountered
by Monarchs in the field because they lack ... the biological data on
milkweed distribution and the occurrence of Monarchs," Shelton said. "More
detailed and extensive field studies are being done by a group of
independent scientists from the U.S. and Canada. So far, they have failed
to see the effects predicted (by the Iowa State authors)," he added.

It seems Bt corn research only sees the light of day when researchers kill
Monarch butterfly larvae through unrealistic conditions. It's not good
science. But, like Survivor, it makes good television.
- Steven Milloy is a biostatistician, lawyer, adjunct scholar at the Cato
Institute and publisher of http://www.Junkscience.com.

Re: AGBIOVIEW: BT and Monarchs
Date: Thu, 24 Aug 2000 4:05:38 PM Eastern Daylight Time
From: "L. Val Giddings"

By Obrycki's own admission, Monarch laravae are present in his area from
June through September. That's sixteen weeks. Corn pollen is famous for
being not only big sticky and heavy, but also ephemeral. From a given
field corn pollen is typically shed for a maximum period of 2 weeks, the
majority over 3-5 days, depending on weather, staggered
plantings/germination/maturation, etc. So the maximum likely worst case
overlap in a given location in Obrycki's region is 2 weeks out of sixteen,
or 12.5% .

We know further that most of the Monarch range is not contiguous with corn
growing regions (45% overlap according to Losey). We also know that
milkweed is on the federal list of noxious weeds, and farmers tend to
extirpate it given the slightest opportunity. The result is that most
milkweed is found outside corn fields. Of all the land outside corn
fields, far more is at a distance greater than one meter rather than less,
at which distance corn pollen concentrations become trivially small. This
means most
milkweed is not likely to carry significant concentrations of corn pollen
for more than a fleeting portion of the Monarch larvae's life time. Put
all these factors together and one is left with the inescapable conclusion
that in the worst case most monarch larvae are unlikely ever to encounter
corn pollen of any sort in the real world.

These and numerous other mitigating and contextual factors leave the cold
eyed skeptic with one obvious conclusion -- this issue is a gigantic red
herring. It may sell newspapers and TV ad time, but Monarchs are not
significantly threatened by corn pollen of any sort. Their major threats
continue to be habitat distruction and predators like automobile

Date: Thu, 24 Aug 2000 5:08:10 PM Eastern Daylight Time
From: stacy.charlton@nabri.Novartis.com

RE: Levels of Cry 1Ab in corn pollen.

The recently published Iowa State study looked at two Novartis Bt corn
events, Bt11 and event 176. Bt11 is fairly typical of other corn events
on the market with the Bt gene being driven by the constitutive 35S
promotor, 176 is engineered specifically to express in green tissue and

Studies submitted to the EPA in 1997 indicate that hemizygous Bt11 plants
express less than 90 ng of Cry 1Ab protein per gram pollen (dry weight)
while hemizygous event 176 plants express from 2-8 micrograms of Cry1Ab
protein per gram pollen (dry weight). Thus there is a substantial
difference between event 176 and Bt11in the amount of Bt expressed in

One of the curious aspects of the Obrycki study was that this difference
was not reflected by the mortality data nor did there appear to be a
significant dose response relation ship between either distance of the
milkweed plants from the corn field or the number of pollen grains counted
on the leaf disks.

Mark Sears' study can be found on the web at:


Stacy Charlton

Subj: news stories
Date: Thu, 24 Aug 2000 5:42:09 PM Eastern Daylight Time
From: "Bob Bowden"

The AP report that was posted to AgBioView list 8/24 (Message #751
)contains some embarrassing
factual errors attributed to me. I think I need to explain what happened.
A local newspaper reporter attended the farmer meeting where I spoke and
obviously didn't get the story quite straight. This is normal in my
experience. I never got a chance to check the story for accuracy. This is
also normal in my experience. The surprising thing was that the AP wire
picked it up. It must have been a slow news day.

The reporter confused my discussion of the Losey paper with a discussion
of some unpublished pollen transport and toxicity data kindly supplied to
me by Dr. Richard Hellmich. Hellmich had found some minor growth effects
are likely up to 1 meter away for events MON810 and CBH351. Event 176
hybrids were more toxic and showed some probable effects out to 4 meters.
The reporter failed to note the important distinction between different
transformation events and incorrectly attributed the
distance effects to Losey. There were several other errors.

In addition, I sounded a bit uncaring when I said, "Until somebody is
going to pay us to worry about it, we shouldn't worry about it." I was
responding to the question of whether farmers should avoid planting Bt
corn from an economic point of view. I had already discussed the
environmental aspects. Context adds a lot to meaning.

This episode shows how little control we often have over news stories;
they get a life of their own. Although it would be nice for reporters to
have their stories checked, that is close to sacrilege for some of them.

Bob Bowden


Subj: RE: AGBIOVIEW: Monarchs and Bt
Date: Fri, 25 Aug 2000 8:32:57 AM Eastern Daylight Time

Dear All:

For a long time, I have been a silent witness to the barrage of exchange
of letters, opinions, so called "facts", criticisms, and outright
grand-standing on a variety of positions related to discussions on public
concerns on biotechnology for about six monthson your forum. Time has
come to ask a simple question of ourselves: Is this serving any purpose?
Is anyone getting better educated or better informed? More importantly,
has anyone's mindset has been changed or altered. I think not. The
reason is simple. This is not debate. It is cacophony. People are
getting bored and tired of all sorts of rhetoric. I feel it is time to
change the tactic of trying to brow beat each other and stop this
meaningless one upmanship. The ongoing "tit for tat" cat fight is only
polarizing the believers and non-believers. It is certainly not building
consensus. Perhaps it is time to shut up for all and let there be some
calm time for a couple of months.

What inspired me to dash off this note is the flood of opinions and
criticisms offered in response to the Bt-Corn-Monarch paper in Oecologia.
It seems that for the anti-biotech people, any small negative publication
is yet another weapon to cry hoarse and immediately proclaim "we told you
so". On the other hand, for pro-biotech groupies, no experiment is close
enough to reality and as such have no relevance. But, all of you know
that a field level realistic experimentation would take several years and
there is no support for such an activity. By continuing to squabble the
way I have seen it so far, no one is winning and is only vitiating the
atmosphere. On the toehr hand, all of us may be helping those people who
are out to stop bitoech to firm their resolve even more.

On the other hand, there ever so many new alternative technologies other
than rDNA biotechnology that are showing promise that need some press in
this forum. For a change, why not discuss the merits of the newly
published in NATURE Vol 406 2000 entitled Genetic Diversity and Disease
Control in Rice by Youyong Zhu et al. This is a wonderful instance of
realistic large scale experimentation to control rice blast disease. I am
sure there are many more such new technolgoies and agricultural practices
being developed that will have real practical value that needs to be show
cased and promoted for the good of all.

Shall we call for a moratorium on the biotech squabble for a while what
effect it might have? Thanks for listening.

Sivramiah "Shanthu" Shantharam
Visiting Research Fellow
International Food Policy Research Institute (IFPRI)
2033 K Street, NW
Washington, D.C. 20006
Tel: (202) 862-8158
Fax (202) 467-4439