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RISK ASSESSMENT
Having identified a list of possible harms
that might occur as a result of using or releasing genetically
engineered organisms, the next question is how likely are
any of these to occur? Like the original "brainstorming"
of potential harms, the answer to this question depends greatly
on how well the organisms and their interaction in the environment
are understood.
Risks must be assessed case by case as new
applications of genetic engineering are introduced. In some
circumstances, it is possible to assess risks with great confidence.
For example, it is vanishingly unlikely that genetically engineered
palm trees will thrive in the Arctic regardless of what genes
have been added. But for many potential harms, the answers
are far less certain.
Risk assessments can be complicated. Because
even rigorous assessments involve numerous assumptions and
judgment calls, they are often controversial when they are
used to support particular government decisions. For example,
the approval of the first genetically engineered squash by
the United States Department of Agriculture involved a controversial
risk assessment.
Under the current US regulatory framework for
biotechnology, some sort of risk assessment is routinely produced
before decisions to allow commercialization of products under
the Federal Plant Pest Act; the Federal Insecticide, Fungicide,
and Rodenticide Act (FIFRA); and the Toxic Substances Control
Act (TSCA).
In the case of the Plant Pest Act, risk assessments
are done according to the procedure specified by the National
Environmental Policy Act (NEPA). Under NEPA, risk assessments
could lead to full-blown environmental impact statements,
but so far all evaluations of engineered agricultural organisms
have led to the legal conclusion that no environmental impact
statement is needed.
For the most part, risk assessments are done
by scientists and policymakers in the relevant agencies (USDA
or EPA) with information provided by the companies seeking
the approvals. The public often has a brief opportunity to
review and comment on the risk assessments.
There is no standard set of questions that
risk assessments must answer because of the great range of
potential impacts of biotechnology products. A risk assessment
for a microbial pesticide, for example, would be substantially
different from a risk assessment for genetically engineered
salmon. Like all efforts at risk evaluation, risk assessments
done for regulation depend on the base of scientific knowledge
for generation of list of possible harms to be assessed.
Bioballistics
Finally, there are so-called projectile methods
that use metal slivers to deliver the genetic material to
the interior of the cell. The small slivers (much smaller
than the diameter of the target cell) are coated with genetic
material. One projectile method, called bioballistics, propels
the coated slivers into the cell using a shot gun. A perforated
metal plate stops the shell cartridge, but allows the slivers
to pass through and into the living cells on the other side.
Once in the cell, the genetic material is transported to the
nucleus where it is incorporated among the host genes.
Contrary to the arguments made by some proponents, genetic
engineering is far from being a minor extension of existing
breeding technologies. It is a radically new technology for
altering the traits of living organisms by inserting genetic
material that has been manipulated by artificial means. Because
of this, genetic engineering may one day encompass the routine
addition of novel genes that have been wholly synthesized
in the laboratory.
Novel organisms bring novel risks, however,
as well as the desired benefits. These risks must be carefully
assessed to make sure that all effects-both desired and unintended-are
benign. UCS advocates caution, examination of alternatives,
and careful case-by-case evaluation of genetic enginering
applications within an overall framework that seeks to move
agricultural systems of food production toward sustainability.
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