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Issue: Impact on non-target organisms
There has been much media attention given
to the potential impact of GM crops on non- target organisms. An ideal
pest control tactic would be one that controls the pest, but does not
harm other non-target organisms in any way. Non-target organisms include
all organisms except for the pest to be controlled. Examples of
non-target organisms would be mammals,
fish, birds, reptiles and other insects.
Examples of non-target insects to be protected
include lady beetles, lacewings, and other insect predators, honey bees and other insect
pollinators, and butterflies and other aesthetically pleasing insects.
 Lady Beetle
 Lacewing
 Monarch
Media attention has focused on Bt-corn and the impact that it may have
on monarch butterflies.
At one time, some believed that Bt plants
would be the idea control of some crops pests, because only the pests
that fed on the plant would ingest the toxin and the toxin is only toxic
to some plant feeding insects. However, some Bt-corn plants have relative
high levels of the Bt protein in their pollen, and pollen released from
these plants may fall on other plants and be eaten by other insects that
are not pests. In the case of the monarch caterpillars, pollen from the
Bt corn drifts onto milkweed plants which are common in and near corn
fields. As the monarch feeds on the milkweed leaves, it ingests the Bt
pollen and some caterpillars are killed.Effects on non-target organisms is and will
continue to be an important issue. New GM crops will need to be evaluated
for their potential effects on non targets. However, a double standard
has arisen for regulating non target effects, one for insecticides and
the other for GM crops. Many of the insecticides used today are considered
broad spectrum- meaning they kill a wide range of insects including
beneficial ones.
Many are classified as Restricted Use Pesticides due to their toxicity
to fish, birds, or other wildlife. Relative to most insecticides on the
market, Bt-crops are more selective and potentially less damaging to non-target
organisms.
Impacts of Bt cotton and corn on non-target arthropods
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