Transcript All GE crops are not alike and thus cannot be discussed as a

Scary Food
Many packaged food products are recalled
from the American market due to the
presence of all-natural contaminants:
– insect parts
– toxic molds from fungi (mycotoxins)
– Bacteria
– viruses
Ergot Poisoning
• Europe 800s-1800s
• epidemics caused by the contamination of
rye with ergot (a poisonous fungus)
• Ergot toxin is ergotamine
• consumption induces hallucinations,
bizarre behavior, violent muscle twitching
1691-92 Salem witch trials
• Three young girls
– violent convulsions, incomprehensible speech
– trance-like states, odd skin sensations,
– delirious visions
•Villagers feared the girls were under a spell cast by demons;
subsequent panic led to the execution of ~ 20 innocent
people.
•rye was a major staple of their diet
•rainy and humid rye harvest that year
•When the supply of Ergot- infected rye ran out,
the delusions and persecution disappeared.
Fumonisin Poisoning
• a deadly mycotoxin produced by the mold
Fusarium
• sometimes found in unprocessed corn
• Can cause liver and esophageal cancer,
birth defects
when insects attack corn, they open wounds
in the plant that provide a perfect breeding
ground for Fusarium.
1990s: Hispanic women in the Rio Grande
Valley of Texas
• 6 times the national average of babies with
crippling and lethal neural tube defects
(NTDS)
– spina bifida, Hydrocephalus, anencephaly
• NTDS linked to consumption of
unprocessed corn
•These women reported much higher dietary
consumption of homemade corn tortillas
containing 2-3 x more fumonisin than normal
Know your Organic Food
• 2003 - Food Safety Agency tested six
organic cornmeal products and twenty
conventional corn meal products for
fumonisin contamination.
•All six organic corn meals had 9
to 40 times greater fumonisin
than the recommended levels for
human health (they were
voluntarily withdrawn from
grocery stores.)
Genetically Modified (GM) Foods
99% of GM foods in food supply are
– Round-up Ready™ soybeans
– Bt corn
Round-up Ready
Soybeans/cotton
• Round-up (an herbicide) kills weeds
• It degrades in the environment when used
properly (sunny and dry weather).
• Crops can engineered to be tolerant to
Round-up, so it can be used rather
than more toxic herbicides
Bt corn contains a gene from the bacterium
Bacillus thuringiensis.
The "Bt" gene expresses a protein that is toxic to
corn-boring insects but is harmless to birds, fish,
and mammals (including humans).
Bt corn fends off insect pests
Also reduces the levels of the mold Fusarium
Are GM foods SAFE?
• Round-up Ready corn/soybeans and Bt
corn consumed in United States, Argentina
and Canada Since 1995
• not a single case of adverse health
impacts has been documented
•Bt is considered safe to eat because it is
digested in minutes and is not absorbed
as a whole protein by the body.
BEWARE of Public Skepticism
Golden Rice
• two daffodil genes and a bacterial gene
spliced into the rice genome. – barely
produced enough b-carotene
• Now golden rice contains a corn gene that
provides enough b-carotene
• Still not available due to regulations
Outdated Propaganda against
Golden Rice
A normal size serving
would be sufficient
with the newer golden
rice
1999 Gerber foods company succumbed to activist
pressure “baby food products no longer contain
any gene-spliced ingredients”
• Gerber promised a shift to organic ingredients that
are grown without synthetic pesticides or fertilizers
• Gerber has actually increased the health risk for
its baby consumers.
• If a mother some day discovers that her "Gerber
baby" has developed liver or esophageal cancer,
she might have a legal case against Gerber
Benefits of GE crops
• reduced use of chemical pesticides
• less runoff of chemicals into waterways
• greater use of farming practices that
prevent soil erosion
• higher profits for farmers
• less fungal contamination
• More nutritious foods
GE crops and Worker Safety
• Production of Bt cotton has led to enormous
reductions in insecticide use (equivalent to 25
percent of all of the insecticide sprayed before
the adoption of Bt cotton).
• Reduced exposure of farm workers to broadspectrum pesticides
• the positive effects on farm workers and the
environment should be considered when
deciding on the merits of Bt crops
GM Concern
• Pests will evolve to become resistant to Bt
(This also normally occurs if a pesticide is
heavily used)
• Many varieties of Bt toxin can be
genetically engineered to keep one step
ahead of the insects.
GE crops can coexist with other
farming systems
• the papaya industry in Hawaii was virtually
decimated by the presence of a single viral
disease caused by the papaya ringspot virus
• 1998: genetically engineered papaya lead to a
20-fold increase in yield.
• Hawaiian organic papaya can be grown disease
free if it is produced near GE trees. This is
because the GE fruit has eliminated the spread
of the virus.
Food Labeling
• a “GMO-free” label does not provide
meaningful information.
• Example: GE papaya is immunized with
trace amounts ringspot viral DNA
• organic papaya is likely to be virally
infected and would therefore carry much
higher levels of viral RNA as well as viral
protein.