Impact of GMO’s on Non-Target Organisms

1. Impact of GMO’s on Non-Target Organisms

Impact of GMO’s on NonTarget Organisms
Peter C. Ellsworth, Ph.D.
IPM Specialist, University of Arizona
&
Steve Naranjo, Ph.D.
Research Scientist, USDA-ARS, WCRL
Ellsworth/UA

2. Disclosure

• Those engaged in the dialog on biotechnology
should fully disclose their relationships and
opinions “up front” so that audiences can
consider the context.
• Partial support for my research comes from
companies with interests in biotechnology.
• The balance of support comes from state and
federal sources of competitively available public
funds.
Ellsworth/UA

3. Disclosure (continued)

• Biotechnology and its
products are neither
inherently good nor bad.
• The specific process and
each of its products should
be scientifically and
independently evaluated.
Ellsworth/UA

4. Science or Emotion?

• Proponents and opponents of biotechnology
have made ample use of both.
• However, emotion tends to rule in the court of
public opinion.
Ellsworth/UA

5. Public Opinion

• “Unintended
consequences:
pelicans nearly
wiped out by DDT,
massive radiation
leaked at
Chernobyl, now
butterflies killed by
genetically modified
corn…”
Full page back cover of “blue”
magazine; Patagonia, 2001
Ellsworth/UA

6. Public Opinion

• “… The list of environmental damage caused by
inadequately tested technologies is long. With
genetic engineering unleashed on the world the
list may grow much, much longer. We don’t yet
know all the impacts and dangers of genetic
engineering. Shouldn’t we find out the risks
before we turn genetically modified organisms
loose on the world, or eat them in our food?”
Ellsworth/UA

7. Public Opinion

“Our species, as yet
unable to see the
whole, or to know how
it works, now stands
poised...
...with an X-Acto
blade to cheat the
outcome: to solve the
puzzle by reshaping its
pieces to our own
devising.”
From
www.patagonia.com/enviroaction;
Patagonia, 2001
Ellsworth/UA

8. Are Scientists Mad?

“For the past decade, biotech’s mad scientists have
been telling consumers not to worry about
Frankenstein foods….
…The biotech industry and governments have
done almost no safety testing of GE foods….
…Millions of acres of GE crops are spreading
genetic pollution, creating superweeds and pests,
disrupting the balance between pests and natural
predators, and killing butterflies and beneficial
soil microorganisms. The more we learn about
Frankenfoods and crops, the scarier they
appear.”
From BioDemocracy News #40, “The Death of Frankenfoods”, August 2002
Ellsworth/UA

9. Powerful Imagery

Bikini Atoll
Mad Cow Disease
“And we now
have a solid
Asbestos modern history
Brown Pelican &of
DDT
stuff that’s
Thalidomide Babies
come out of
labs that should
have stayed
there.”
Patagonia, 2002
Ellsworth/UA

10. GMO’s: Social Platform?

• Starbucks Global Week of
Action (Sept. 21-28, 2002)
• Remove genetically engineered
ingredients from their food and
dairy products on a worldwide
basis,
• Improve working conditions for
coffee plantation workers, and
brew and seriously promote fair
trade coffee in all of their cafes.
From Organic
Consumers
Association;
organicconsumers.org
Ellsworth/UA

11. World Food Deprivation

Ellsworth/UA

12. A Hungry Planet?

• 1.85 Billion people (30%) are hungry
in the world today (FAO, 2002).
• 36 Million people (13%) go hungry in
the U.S. today (USDA, 2002).
• 2.5 - 6 Million people (20-50%)
starving in Zambia today, yet…
• Zambian President Levy
Mwanawasa recently rejected FREE
corn (10,000 tons) offered by the
U.S., because it was not GMO-free.
Ellsworth/UA

13. So What Is The Story?

• Monarch Butterfly,
symbol of nature and
“wildness” in North
America.
Ellsworth/UA

14. Incredible Annual Migration!

Ellsworth/UA

15. Monarchs Feed on Milkweed

Ellsworth/UA

16. Bt Corn Sheds Pollen

• Some of which
may fall on
milkweed plants
that serve as
hosts for
Monarchs.
• Bt corn pollen
may contain some
quantity of the Bt
endotoxin.
Ellsworth/UA

17. Monarchs Are Killed?

• Scientists have
shown that larvae
are killed when fed
milkweed “dusted”
with Bt corn pollen.
• But how realistic
was this study?
Ellsworth/UA

18. PNAS: Temporal & Spatial Distribution of Monarchs…

PNAS: Temporal & Spatial
Distribution of Monarchs…
• Per plant densities of larvae, similar among
habitats (i.e., ag. vs. non-ag. lands)
• For upper Midwest, most Monarchs are, in fact,
produced on agricultural lands!
• Regardless of Bt corn, other agricultural
practices like foliar insecticide use and weed
control could have large impacts on populations
of Monarchs
From Oberhauser et al., 2001
Ellsworth/UA

19. PNAS: Corn Pollen Deposits on Milkweed…

• Average 171 pollen grains per sq. cm. in corn
fields
• Average 14 pollen grains per sq. cm. 6 ft outside
of the corn field
• One rain removes 54-86% of the pollen
• Youngest leaves, the preferred food, have 50-70%
lower pollen density than older leaves
From Pleasants et al., 2001
Ellsworth/UA

20. PNAS: Toxicity of Bt Proteins & Corn Pollen

PNAS: Toxicity of Bt
Proteins & Corn Pollen
Bt Toxin
1st instars
on diet
1st instars on
pollen on discs
Cry1F
Non-Toxic
Non-Toxic
Cry9C
Non-Toxic
Non-Toxic
Cry1Ac
Toxic
Non-Toxic
Cry1Ab
Toxic
Toxic (Event 176 only)
From Helmich et al., 2001
Ellsworth/UA

21. PNAS: Field Mortality of Monarchs…

• 50% of Monarch larvae died in the first 24 hrs
– NONE related to proximity to Bt corn
• But slower growth of Black Swallowtails likely
related to pollen exposure
– for Event 176 (Novartis) only
From Zanger et al., 2001
Ellsworth/UA

22. PNAS: Field Impact of Cry1Ab (3 events)…

Exposure Density
& Duration
Cry1Ab
Event 176
Cry1Ab
Bt11
Cry1Ab
Mon810
22 gr. / sq. cm.
Weight loss
(-18%)
--
--
67 gr. / sq. cm.
Weight loss
(42%) &
mortality
(40%)
NOE
--
97 gr. / sq. cm.
NOE
--
500+ gr. / sq. cm.
NOE
--
In-field feeding for
14-22 d
NOE
NOE
Compared
to lambdacyhalothrin
which killed
most
Monarch
larvae
From Stanley-Horn et al., 2001
Ellsworth/UA

23. PNAS: A Risk Assessment...

Hazard =
Acute toxic effects of pollen
X
Exposure =
Probability of larvae being exposed to
toxic levels in and around corn fields
Risk =
“This two year study suggests that the
impact of Bt corn pollen from current
commercial hybrids on Monarch Butterfly
populations is negligible.”
From Sears et al., 2001
Ellsworth/UA

24. Non-Target Organisms (NTO)

• Search for unintended consequences
of technology (e.g., Bt cotton) on
biodiversity.
• Through direct effects, i.e., toxic
effects on non-target species,
• Or through indirect effects, i.e.,
through non-target species feeding on
intoxicated hosts.
Ellsworth/UA

25. Natural Enemy Abundance No Insecticides

1999
2000
16000
12000
8000
Bt cotton
Non-Bt
P = 0.18
P = 0.29
6000
8000
4000
4000
2000
0
n
n
ul Aug Aug
ep
S
9 Ju 29 Ju 19 J
7
8
8
1
2
0
g
p
n
g
n
ul
9 Ju 29 Ju 19 J 8 Au 28 Au 17 Se
Ellsworth/UA

26. Natural Enemy Abundance Insecticides as needed

Cum arthropod-days (50 sweeps)
Cultivar
Insecticides
6000
Bt cotton
Non-Bt
5000
Unsprayed
Sprayed
4000
3000
P = 0.001
2000
1000
P = 0.92
0
29 Jun
8 Aug
17 Sep
29 Jun
8 Aug
17 Sep
Ellsworth/UA

27. Non-Target Organisms (NTO)

• Over 370 arthropod species have been tracked in
2 years of field studies using a variety of
methodologies.
• So far, no major or functional differences have
been found in Arizona between BG, BGII, and
conventional cotton communities…
• Except where harsh PBW sprays are needed in
conventional cottons.
• Thus, Bt cotton ecosystems are not only safe, but
safer than conventional cotton ecosystems where
insecticidal inputs are higher.
Ellsworth/UA

28. Information

• All University of Arizona
crop production & crop
protection information is
available on our web site,
A
C
I
S
• Arizona Crop Information
Site (ACIS), at
• http://ag.arizona.edu/crops
http://ag.arizona.edu/crops/presentations/presentations.html
Ellsworth/UA