Food, Soil, and Pest Management - Environmental Science - page 221

Despite its promise, considerable controversy has
arisen over the use of genetically modified food (GMF) and
other forms of genetic engineering. Its producers and
investors see this kind of food as a potentially sustain-
able way to solve world hunger problems. Some critics
consider it potentially dangerous “Frankenfood.” Fig-
ure 10-19 summarizes the projected advantages and
disadvantages of this new technology.
Critics recognize the potential benefits of geneti-
cally modified crops. At the same time, they warn that
we know too little about the potential harm to human
health and ecosystems from the widespread use of such
crops. Also, genetically modified organisms cannot be
recalled if they cause some unintended harmful genetic
and ecological effects—as some scientists expect.
Most scientists and economists who have evalu-
ated the genetic engineering of crops believe that its
enormous potential benefits outweigh the much
smaller risks. Critics call for more controlled field ex-
periments, more research and long-term safety testing
to better understand the risks, and stricter regulation
of this rapidly growing technology. A 2004 study by

the Ecological Society of America recommended more
caution in releasing genetically engineered organisms
into the environment. Although a 2004 National Acad-
emy of Sciences study found no evidence that geneti-
cally engineered crops have harmed human health
more than crops created by conventional crossbreed-
ing, it called for federal regulators to look more closely
at the potential health effects of genetically modified
plants before approving them for use as commercial
crops.

x

H OW W OULD Y OU V OTE ? Do the advantages of genetically
engineered foods outweigh their disadvantages? Cast your
vote online at http://biology.brookscole.com/miller11.

Many analysts and consumer advocates believe
governments should require mandatory labeling of
GMFs. Consumers would then have more information
to help them make informed choices about the foods
they buy. Such labeling is required in Japan, Europe,
South Korea, Canada, Australia, and New Zealand
and was favored by 81% of Americans polled in 1999.
Industry representatives and the USDA oppose
such labeling, claiming that GMFs are not substan-
tially different from foods developed by conventional
crossbreeding methods. Also, they fear—probably cor-
rectly—that labeling such foods would hurt sales by
arousing suspicion.

T rade-Offs

Genetically Modified Crops and Foods

Projected
Advantages

Projected
Disadvantages

Learn more about how genes are modified and used to
create plants with new traits at Environmental ScienceNow.

Need less fertilizer Irreversible and

unpredictable
genetic and
ecological effects

Need less water

x

H OW W OULD Y OU V OTE ? Should all genetically engi-
neered foods be so labeled? Cast your vote online at
http://biology.brookscole.com/miller11.

More resistant
to insects, plant
disease, frost, and
drought

Harmful toxins in
food from possible
plant cell mutations

New allergens
in food

Faster growth

Science: Problems with Expanding
the Green Revolution
Lack of resources, such as water and fertile soil, and
environmental factors may limit our ability to
continue increasing crop yields.
Many analysts believe we can produce all the food we
need in the future by spreading the use of existing
high-yield green revolution crops and genetically en-
gineered crops to more of the world.
Other analysts disagree. They point to several fac-
tors that have limited the success of the green and gene
revolutions to date and may continue to do so. With-
out huge amounts of fertilizer and water, most green
revolution crop varieties produce yields that are no
higher (and are sometimes lower) than those from tra-
ditional strains. Also, green revolution and genetically
engineered crop strains and their high inputs of water,
fertilizer, and pesticides cost too much for most subsis-
tence farmers in developing countries.

Can grow in
slightly salty soils

Lower nutrition

Increases
development of
pesticide-resistant
insects and plant
diseases

Less spoilage

Better flavor

Less use of
conventional
pesticides

Can create
herbicide-resistant
weeds

Tolerate higher
levels of
herbicide use

Harm beneficial
insects

Lower genetic
diversity

Higher yields

Figure 10-19 Trade-offs: projected advantages and disad-
vantages of genetically modified crops and foods. Critical think-
ing: pick the single advantage and disadvantage that you think
are the most important.