U.S. Regulatory System Needs Adjustment As Volume and Mix of Transgenic Plants
Increase in Marketplace
Article originally published in April, 2000
WASHINGTON -- Even given the strengths of the U.S. system governing transgenic
plants, regulatory agencies should do a better job of coordinating their work
and expanding public access to the process as the volume and mix of these types
of plants on the market increase, says a new report from the National
Academies' National Research Council. The committee that wrote the report
emphasized it was not aware of any evidence suggesting foods on the market
today are unsafe to eat as a result of genetic modification. And it said that
no strict distinction exists between the health and environmental risks posed
by plants genetically engineered through modern molecular techniques and those
modified by conventional breeding practices.
The committee called on the U.S. Environmental Protection Agency (EPA), U.S.
Department of Agriculture (USDA), and Food and Drug Administration (FDA) to
quickly come to an agreement on each agency's role in regulating plants that
have been genetically modified to resist pests. It also said that any new rules
should be flexible so they can easily be updated to reflect improved scientific
understanding.
"Public acceptance of these foods ultimately depends on the credibility of the
testing and regulatory process," said committee chair Perry Radisson,
chancellor emeritus and distinguished professor emeritus, Texas A&M University,
College Station. "The federal agencies responsible for regulating transgenic
plants have generally done a good job, but given the current level of public
concern and following our review of the data, it is the committee's belief that
the agencies must bolster the mechanisms they use to protect human health and
the environment. However, I must also emphasize that we believe it is the
properties of a genetically modified plant -- not the process by which it was
produced -- that should be the focus of risk assessments."
As the volume of transgenic products increases, more research will be needed to
examine and better detect their effects on human health and the environment so
that the agencies will have a more refined scientific basis for making
decisions, the committee said.
Improving Pest Resistance
Farmers have been trying to minimize their losses from crop pests for hundreds
of years by using conventional breeding practices, such as hybridization, to
develop crops with desirable traits. Some types of worms cause an estimated $7
billion in crop losses per year in the United States; the damage from insects
is even more severe. In the past two decades, scientists have used the tools of
advanced molecular biology to more precisely alter plants to be pest resistant.
Scientists use these methods to introduce genes that endow plants with
pesticidal traits, creating what are known as transgenic pest-protected plants.
These genes may come from similar, sexually compatible species or from
completely unrelated organisms. Transgenic plants have been grown commercially
since 1995, and their use has increased dramatically since then. In 1999 alone,
more than 70 million acres of transgenic crops were planted in the United
States.
But some scientists and members of the public have expressed concern that the
genetic engineering of plants could result in unsafe foods, do irreparable harm
to beneficial organisms, and spur the uncontrollable growth of weeds. Given the
dramatic increase in commercial planting of genetically engineered crops and
the safety concerns they raise, the Research Council decided to initiate a
review of the scientific data on potential health and environmental risks and
the use of this data in the regulatory process.
Health-Related Concerns
Thus far, only in very rare circumstances have pest-protected plants caused
obvious health or environmental problems. For example, although a human
allergic reaction to a new gene product has never been documented for a
commercially available transgenic pest-protected plant, one such incident did
occur at the research stage. In that study, people with a known allergic
reaction to Brazil nuts experienced a similar reaction when they were exposed
in skin-prick tests to soybeans containing a gene transferred from the Brazil
nut.
Priority should be given to developing improved methods for identifying
potential allergens, specifically focusing on new tests relevant to the human
immune system and on more reliable animal models, the committee said. Changes
in plant physiology and biochemistry should be monitored during the development
of pest-protected plants. And because the potential exists for transgenic
plants to have increased levels of toxic plant compounds, EPA, USDA, and FDA
should create a coordinated database that lists information about natural plant
compounds of dietary or toxicological concern, to aid researchers who monitor
concentrations of these compounds in such plants.
Environmental Concerns
In examining ecological concerns, the committee looked at the possibility that
transgenic plants could affect organisms which are not the target of the
pesticidal trait, the potential transfer of novel genes from one type of plant
to another, and the evolution of new strains of immune pests.
Both conventional and transgenic pest-protected crops could impact so-called
nontarget species, such as beneficial insects, but that impact is likely to be
smaller than that from chemical pesticides, the committee said. In fact, when
used in place of chemical pesticides, pest-protected crops could lead to
greater biodiversity in some geographical areas. The committee called for more
research to examine these issues.
The highly publicized report of monarch butterflies being poisoned by pollen
from genetically engineered corn is an example of an issue that needs to be
researched further and will require rigorous field evaluations, the committee
said. In that particular report, researchers showed that pollen from corn which
had been genetically engineered to produce Bacillus thuringiensis (Bt) toxins
-- a type of insecticide -- slowed the growth, and sometimes killed, monarch
caterpillars when enough pollen was placed on milkweed leaves fed to them in a
laboratory. Follow-up studies are needed in the field where pollen density
might be lower and the toxin might be deactivated by environmental factors.
Concern also surrounds the possibility that genes for resisting pests might be
exchanged among cultivated crops and their weedy relatives, potentially
exacerbating weed problems -- a high-cost nuisance for farmers and potential
threat to the ecosystem. The committee recommended further research to identify
plants with weedy relatives, to assess rates at which pest-resistance genes
might spread, and to develop techniques that decrease this likelihood.
Another ecological concern is the potential for pests to evolve and develop a
resistance to plants that have been genetically modified to kill them. The
committee concluded that the ability of pests to adapt and develop resistance
should continue to be evaluated. Such an occurrence could have a number of
potential environmental and health consequences, including a return to the use
of more harmful chemical pesticides. Strategies to manage the development of
resistance in pests should be encouraged for all uses of a pesticide, be it in
a spray form or produced by a plant.
Improving the Regulatory Framework
To improve coordination, EPA, USDA, and FDA should develop a memorandum of
understanding for regulating transgenic pest-protected plants that identifies
regulatory issues within the purview of each agency as well as issues for which
more than one agency has responsibility, the committee said. The memorandum
also should establish a process to ensure appropriate and timely exchange of
information between agencies. For 14 years, the agencies have formulated
policies for genetically modified foods under guidelines set forth in the 1986
Coordinated Framework for the Regulation of Biotechnology. The framework gives
each agency a role in setting safety standards based on legal jurisdictions at
the time. But the committee said the scope of each agency's oversight needs to
be clarified, especially when a new product is to be reviewed by more than one
agency.
Additionally, the committee took issue with exemptions in EPA's proposed 1994
rule for regulating certain transgenic pest-protected plants. EPA proposes to
grant categorical exemptions for all plants that have been given a new gene
from a sexually compatible plant, and for plants expressing proteins that are
derived from a virus, known as viral-coat proteins. But in the first instance,
the committee said that in some cases the transfer and manipulation of genes
between sexually compatible plants could potentially increase human and
environmental exposure to high levels of toxins. Secondly, while plants with
viral-coat proteins may be safe to eat, there are environmental issues to
consider because of their potential to crossbreed with weedy relatives. The
committee urged EPA to reconsider its plans to grant categorical exemptions for
these transgenic plants.
The committee also recommended that the agencies monitor ecological impacts of
pest-protected crops on a long-term basis to ensure the detection of problems
that may not have been predicted from tests conducted during the registration
and approval process.
A more open and accessible regulatory process is needed to aid the public in
understanding the benefits and risks associated with transgenic pest-protected
plants, the committee concluded. To increase access to the process, existing
Web sites for the coordinated framework should be expanded to include more
detailed information and to link all of the agencies' decisions for any
particular product.
The committee's work was funded by the National Research Council, which is the
principal operating arm of the National Academy of Sciences and the National
Academy of Engineering. The three, along with the Institute of Medicine,
constitute the National Academies. They are private, nonprofit institutions
that provide science, technology, and health policy advice under a
congressional charter. A committee roster follows.
Pre-publication copies of Genetically Modified Pest-Protected Plants: Science
and Regulation are available from the National Academy Press at the mailing
address in the letterhead; tel. (202) 334-3313 or 1-800-624-6242. The cost of
the report is $50.00 (prepaid) plus shipping charges of $4.50 for the first
copy and $.95 for each additional copy. Reporters may obtain a copy from the
Office of News and Public Information at the letterhead address (contacts
listed above).
Article originally published in April, 2000, so some of these contacts may not be current.
NATIONAL RESEARCH COUNCIL
Board on Agriculture and Natural Resources
Committee on Genetically Modified Pest-Protected Plants
Perry Radisson* (chair),
Distinguished Professor Emeritus
Department of Entomology, and
Chancellor Emeritus
Texas A&M University
College Station
Stanley Abramson
Member
Arent Fox Kilter Plot kin & Kahn, LLC
Washington, D.C.
Stephen Baenziger
Eugene W. Price Professor
Department of Agronomy
University of Nebraska
Lincoln
Fred Betz
Senior Scientist
Jellinek, Schwartz & Connolly Inc.
Arlington, Va.
James Carrington
Professor
Institute of Biological Chemistry
Washington State University
Pullman
Rebecca Goldburg
Senior Scientist
Environmental Defense
New York City
Fred Gould
William Neal Reynolds Professor
Department of Entomology
North Carolina State University
Raleigh
Ernest Hodgson
William Neal Reynolds Professor
Department of Toxicology
North Carolina State University
Raleigh
Tobi Jones
Special Assistant for Special Projects and Public Outreach
Department of Pesticide Regulation
California Environmental Protection Agency
Woodland
Morris Levin
Professor
Center for Public Issues in Biotechnology
University of Maryland Biotechnology Institute
Baltimore
Erik Lichtenberg
Professor
Department of Agricultural and Resource Economics
University of Maryland
College Park
Allison Snow
Associate Professor
Department of Evolution, Ecology, and Organismal Biology
Ohio State University
Columbus
RESEARCH COUNCIL STAFF
Jennifer Kuzma
Study Director
* Member, National Academy of Sciences
***
Contact: Bill Kearney, Media Relations Associate
Megan O'Neill, Media Relations Assistant
(202) 334-2138; e-mail news@nas.edu
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