Pharm and
Industrial Crops:
The Next Wave of Agricultural Biotechnology
| Related Links New Freedom Initiative-Bush and the Pharm |
The next wave of agricultural biotechnology -- the pharm and industrial crops -- is moving toward the marketplace. These new crops -- essentially biological factories for a variety of chemical products -- present important new policy challenges that demand a vigorous public debate. We hope this background briefing will help raise the profile of this issue with decisionmakers and engage citizens and consumers in guiding the future of these important new applications of biotechnology.
IntroductionSo far, agricultural biotechnology has concentrated on adding traits--primarily herbicide tolerance and insect resistance (Bt)--that make crops cheaper or easier for farmers to grow and, in some cases, reduce the use of environmentally harmful pesticides. These crops have precipitated a complex and important debate, especially in the global marketplace. Because engineered crops may present risks, particularly to the environment, some critics (including UCS) believe that the federal government must strengthen the regulatory system governing agricultural biotechnology products so that their risks and benefits can be evaluated carefully before they come to market. Others have questioned the taking of any risks to enhance the production of crops already in oversupply.
While that debate still rages, a new generation of agricultural biotechnology crops looms. We're calling the new products-crops engineered as biological factories-pharm and industrial crops.
Some of these applications
(particularly the pharm crops) promise
benefits, such as low cost drugs, important to consumers as well as
farmers. On the other hand, again unlike the plants engineered for new
agronomic traits, pharm crops pose obvious risks. Unless stringently
regulated, gene escape will put biologically active compounds in many
unwanted places in the environment and food supply. No one wants drugs
in their corn flakes.
WHAT ARE PHARM AND INDUSTRIAL CROPS?
Pharm and industrial crops are produced by the same methods used to genetically engineer food crops. Briefly, scientists use recombinant DNA techniques to locate and isolate genes of pharmaceutical or industrial interest. These "transgenes" are then inserted into a crop plant using one of several methods now standard in the industry. The resulting pharm or industrial plant then produces the protein product encoded by the transgene as if it were one of its own naturally occurring genes. Farmers can grow pharm and industrial crops in same way they do unaltered crops.
For most pharm and industrial uses,
scientists plan to extract the
novel proteins (or the compounds produced as a result of the function
of the novel proteins) from the industrial or pharm crop and purify
them before use. In such cases, the new proteins in the crops may or
may not be harmful. In some cases, the novel products will be delivered
in active form to people or animals in the edible fruit or other parts
of the plant.
WHAT KINDS OF SUBSTANCES
DO PHARM AND INDUSTRIAL CROPS PRODUCE?
Scientists and companies are developing and testing a large number of
crops producing pharmaceuticals, biologics, and industrial and research
chemicals. (Biologics are diagnostic or therapeutic products derived
from living sources and are typically complex mixtures not easily
identified or characterized.) A few of the products are discussed
below. Names of many more crop-produced chemicals which are under
development are not available to the public because under federal laws
companies may withhold this information as confidential business data.
Except where noted, the products described have not been
commercialized.
Links
National Academies Bioconfinement Report
Agricultural Biotechnology on the Web
Pharmaceuticals or drugs
Pharmaceuticals (or drugs), which are, generally speaking, chemicals intended
to diagnose, treat, or prevent diseases, are being produced in a number
of pharm plants. Among them are alpha-galactosidase and glucocerebrosidase,
enzymes to treat Fabry's and Gaucher's diseases, respectively.
Other proteins called "defensins" are being manufactured in plants with hopes that their antimicrobial characteristics will make them useful replacements for antibiotics. Drugs are also being produced as anticoagulants, blood substitutes, and hormones, and for wound repair and the treatment of anemia, liver cirrhosis, cystic fibrosis, HIV, and hepatitis B and C.
Biologics
Biologics are complex
biological products such as antibodies, vaccines, and blood products
used in human and veterinary medicine. In the biologics category, pharm
plants are producing antibodies against the bacterium that causes tooth
decay and for treatment of non-Hodgkin's lymphoma. Vaccines against hepatitis
B, rabies, HIV, malaria, autoimmune diabetes, and cholera are being produced
in tobacco, corn, or potato plants. These vaccines will be purified from
the plants before being given to humans, most likely by injection or
as a pill.
Crop-derived vaccines meant to be presented as food (edible vaccines) have been produced against diseases including, among others, measles, polio, diphtheria, yellow fever, and various types of viral diarrhea. These vaccines are being made in tomato fruit and other plant parts that can be eaten raw. (Cooking typically destroys the efficacy of vaccines.)
Plant-produced edible vaccines are also being manufactured for veterinary purposes. Scientists recently conducted clinical trials in which pigs were fed a vaccine produced in corn against transmissible gastroenteritis virus (TGEV), one of the most important diseases in swine. And a vaccine meant to promote resistance to mink enteritis virus, canine parvovirus, and feline panleukopenia virus has been made in blackeyed beans.
Other useful industrial chemicals are the products of chemical reactions driven by enzymes, rather than enzymes themselves. Introducing particular enzymes into industrial crops can result in production of these types of industrial chemicals. For example, the first commercialized industrial crop incorporated a gene from the California bay tree to change the fatty acid biosynthesis pathways in canola. The added gene dramatically altered canola oil composition such that nearly 40% of the oil was comprised of lauric acid, a key raw material in the manufacture of soap, detergents, and cosmetic products. Conventional canola does not contain lauric acid.
WHY ARE COMPANIES PRODUCING DRUGS AND INDUSTRIAL CHEMICALS IN CROPS?
For years, manufacturers have used bacterial fermentation systems or mammalian cell cultures to produce industrial chemicals and drugs. More recently, transgenic mammals have been used as "bioreactors" to make valuable proteins in milk. For several reasons, however, a relatively new sector of the biotechnology industry views plants as preferable for protein production.
Companies have several reasons for turning to plants as biofactories: cheaper production, more flexible manufacturing, and avoidance of controversies associated with animal systems.
Cheaper production
The biggest reason for turning to
engineered crops is cheaper production. Companies believe production
costs will be significantly lower than for bacterial fermentation, cell
cultures, or animal bioreactors systems. The biggest factor in reducing
costs is the high yields of recombinant proteins attainable in
transgenic plants. Production costs for corn systems are estimated to
be between $10 and $100 per gram for proteins that currently cost as
much as $1,000 per gram. Dollar figures based on large-scale tobacco
production vary widely from less than $10 per gram to $1000 per gram.
If realized, the optimistic projections of these companies would represent substantial savings over current costs. Vaccines, for example, can cost thousands of dollars per gram.
Faster, more flexible manufacturing
Using a subsidized commodity like corn and the environment as a
production (although notably not a purification/processing) facility
could cut not only production costs but also capital investment in, and
the time it takes to increase, manufacturing infrastructure. It could
also allow for extremely rapid scale-up (or scale-down) of a production
pipeline in response to market or other factors. New drugs could,
theoretically, become available sooner.
Less controversy than animal production systems
Because most scientists believe that plants cannot transmit animal
pathogens (that can cause diseases like mad cow), the companies
creating pharm and industrial plants promote their products as safer
than animal-sourced proteins. (Plants as bioreactors present their own
risks of product contamination, however, from mycotoxins, pesticides,
herbicides or endogenous plant secondary metabolites like nicotine and
glycoalkaloids.)
Using plants as bioreactors also avoids any animal welfare and certain ethical concerns associated with cloning animals and using them as bioreactors.
Organism-specific advantages
Companies that produce pharmaceutical and industrial proteins in corn
kernels claim their system alleviates problems of product storage,
shipment and purification that often arise with bacterial and animal
models.
More information on why various organizations are producing medicinal
and industrial proteins in plants may be found in the section on
company web sites listed in "related links" above.
WHAT ARE THE POTENTIAL SOCIETAL BENEFITS OF PHARM AND INDUSTRIAL CROPS?
Companies have high hopes that their products will offer substantial societal benefits including lower drug prices for consumers, drugs unavailable any other way, new value-added products for farmers, and inexpensive vaccines for the developing world.
Lower drug prices
Expected savings on infrastructure and production costs lead companies
producing pharm and industrial crops to predict drug prices 10 to 100
times lower than current prices. The cost of treating a patient with
Fabry's disease, currently as much as $400,000 a year, for example, is
predicted to drop to approximately $40,000 annually. Similarly, it is
claimed that the leaves from only 26 tobacco plants could make enough
glucocerebrosidase, currently one of the most expensive drugs in the
world, to treat a patient with Gaucher's disease for a whole year.
Drugs unavailable any other way
Cheap production also means that drugs that could not be produced
cheaply enough at high volume through conventional methods might become
economically viable using genetically engineered crops. Monoclonal
antibodies ("plantibodies") fall into this category. One company's idea
for such a product is a monoclonal antibody against bacteria
responsible for tooth decay, which could be used as a dental
prophylactic. A topical therapeutic for herpes, as well as antibodies
for the treatment of many other diseases, is also under development.
Inexpensive, easily delivered vaccines
Food plants engineered to contain pieces of disease agents can function
as orally administered vaccines, avoiding the need for injection and
syringes. Currently, tomatoes and other vegetables are under
development for that purpose. Although the vaccines would still have to
be standardized for dose and delivered to patients one at a time, the
developers hope that the lower production costs and the convenience of
avoiding refrigeration would make the products attractive to the
developing world.
WHICH CROPS ARE BEING USED?
Corn is by far the most
popular pharm and industrial crop. Since the
early 90's, the US Department of Agriculture has allowed more than 200
field trials of pharm and industrial crops. In nearly three quarters of
these tests, corn has been the crop of choice. Other crops tested
include tomato, rice, barley, alfalfa, sugarcane, soybean, potato,
lettuce, lupine, tobacco, and rapeseed (canola). Significantly, most of
these plants are food crops, many are feed crops, and all of them can
be ingested in some way.
WHAT COMPANIES AND UNIVERSITIES ARE ENGINEERING PHARM AND INDUSTRIAL CROPS?
Below is a list of some of the companies and universities currently involved in the development of pharm and industrial crops, with websites addresses, if available.
Companies
Ventria Bioscience (www.apinc.com)
Boyce Thompson Institute for Plant Research (
http://www.bti.cornell.edu)
CropTech (www.croptech.com)
DuPont (www.dupont.com)
EPIcyte (www.epicyte.com)
Integrated Protein Technologies, a subsidiary of Monsanto (www.iptbio.com)
Large Scale Biology Corporation (www.lsbc.com)
Medicago (www.medicago.com)
Meristem Therapeutics (www.meristem-therapeutics.com)
Planet Biotechnology
ProdiGene (www.prodigene.com)
SemBioSys (www.sembiosys.ca)
Stauffer Seeds (www.staufferseeds.com)
Ventria Bioscience (www.ventriabio.com)
Universities
Iowa State University
University of Hawaii
University of Wisconsin
Washington State University
WHERE ARE PHARM AND INDUSTRIAL CROPS BEING GROWN?
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Field trials of pharm and industrial plants have been allowed
in
Alabama, California, Colorado, Delaware, Florida, Georgia, Hawaii,
Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maryland,
Michigan, Minnesota, Montana, Nebraska, New Jersey, New York, North
Carolina, North Dakota, Ohio, Oklahoma, Oregon, Pennsylvania, South
Carolina, South Dakota, Tennessee, Texas, Virginia, Washington,
Wisconsin, and Puerto Rico.
HOW BIG WILL THE PHARM AND INDUSTRIAL CROP INDUSTRY BE?
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off-site Iowa workshop (PDF) |
Currently, most pharm and industrial crop products are still in the field-testing stage where trials usually start with very small plots, from under one acre to 10 acres. As the crops get closer to commercialization, the size of test plots can increase dramatically. For example, during a government-sponsored workshop held in Ames, Iowa, in April 2000 (see related link), one California-based company claimed to have received a "policy statement" from the USDA indicating that it was "good to go" on a "thousand acres of production material."
Once companies
receive the go-ahead for commercialization, the acres
needed to meet market demand will vary considerably from product to
product. Some may require large plantings. One company estimates that
filling the current US need for a single specific blood protein, for
example, would require a tobacco pharm crop consisting of "thousands or
hundreds of thousands of acres."
By contrast, some products, such as therapeutic vaccines and certain
research chemicals will likely require only tens of acres of pharm or
industrial plants to meet the specific demands of those particular
markets.
ARE ANY PHARM OR INDUSTRIAL CROP PRODUCTS CURRENTLY ON THE MARKET IN THE UNITED STATES?
There are no pharm (pharmaceutical or biologic) products on the market, although several are nearing the end of the development pipeline. At least two research chemicals and one industrial chemical have been marketed and others are expected soon.
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off-site About avidin |
Corn-produced beta-glucuronidase, an enzyme used in research laboratories, was also commercialized in 1997.
Laurate canola, engineered to produce high-laurate oil useful in soaps, cosmetics, and other products, was approved for use in 1995 but has not been a commercial success.
The company producing trypsin in corn plants expects to have limited quantities of this protein, used for industrial, drug, and research purposes, commercially available "in late 2002 with scale up to meet market demand in 2003."
Several vaccines produced in various pharm plants are currently undergoing pre-market testing. Some are in preclinical trials, many are in early clinical tests, and at least one--the non-Hodgkin's lymphoma therapeutic cancer vaccine--is slated for late clinical trials by mid-2002. Regulatory approval for some of these plant-derived medical products is expected by 2004.
In Canada, the anticoagulant,
hirudin, was briefly grown
commercially in transgenic oilseed rape plants. (The company ceased
production because of the potential for contaminating oilseed rape used
for food and feed.)
WILL PHARM AND INDUSTRIAL CROPS DELIVER ON THEIR PROMISE?
As with potential benefits and risks, chances of succeeding in the market place and delivering on promises will vary from product to product.
For example, while developers of edible vaccines have made progress, they have encountered many obstacles. Whole fruits cannot be used as the delivery system, for example, because detached plant organs continue to be metabolically active and vaccine levels may therefore change, either increasing or decreasing, with time after harvest. (Potatoes sprouting in storage are a good example of this metabolic activity.) Processing (at least partially) and batch-monitoring of vaccine-containing fruits would therefore be necessary, making storage and processing-associated costs additional issues that must be addressed before edible vaccines, at least for the developing world, are economically viable.
There are also hurdles to overcome in reducing production costs. The most optimistic estimates often do not include research and development, sales-associated, and other costs. Many, including the president of Baxter Healthcare Corporation's recombinant DNA business, have suggested that purification of some proteins from pharm and industrial plants will pose considerable cost-related challenges. Some analysts have even suggested that extraction and sales of conventional food products like meal, oil, and starch might be necessary to make some pharm and industrial crops economically viable.
Purification will be a big issue, especially for the drugs and vaccines. Standards of purity for vaccines and drugs are very high. Effectively purifying foreign proteins away from plant-produced contaminants and/or agricultural products like pesticides could prove formidable.
Even if costs of production are reduced, those savings may
not be
passed on to consumers as lower prices. Virtually none of the
biotechnology food products on the market today in the United States
deliver price benefits to consumers.
WHAT ARE THE RISKS ASSOCIATED WITH PHARM AND INDUSTRIAL CROPS?
Many of the novel substances produced in pharm and industrial crops exhibit high levels of biological activity and are intended to be used for particular purposes, under very controlled circumstances. None of these substances is intended to be incorporated in food or to be broadcast into the environment.
The magnitude of the risks such crops pose depends on many factors including which chemicals are involved, what organisms or environments are exposed, and the level and duration of the exposure. Humans, animals and the environment at large may be at risk.
The major concern at this point is that that non-food substances will contaminate the food supply. Substances intended for use as human drugs are especially problematic because they are intended to be biologically active in people.
Below is an overview of some potential harms to human and animal health and ecosystems, followed by a section on how genes might escape from the fields in which they will be grown.
Potential harms to human
and animal health
The novel chemicals produced by pharm and industrial plants are
generally proteins or short polypeptides. (Some novel proteins, in
turn, produce chemicals that usually are not proteins.) Both proteins
and non-proteins can harm people and animals. Some proteins can act,
among other things, as toxins, hormones, or allergens.
Chemicals vary in form and activity through their production cycle and are not always harmful. To illustrate, hirudin, a powerful blood thinner for treatment of heart attacks and strokes, was grown in canola as an inactive compound: only after extraction and purification from canola seeds did it become biologically active.
In addition, the intended mode of use can affect the likelihood of harm. Just because a substance would be bioactive if injected, for example, does not mean that it would be harmful if ingested.
Some of the most problemmatic substances include toxins, hormones, and allergens.
Toxins
Avidin
is an example of a potential toxin. Avidin binds extremely tightly,
essentially irreversibly, to biotin, a B vitamin necessary for basic
metabolism. The tightness of the avidin-biotin bond makes avidin useful
as a tool in research laboratories. Binding biotin effectively
inactivates it, which can lead to biotin deficiency in living beings,
including humans.
Biotin deficiency in humans (www.emedicine.com/ped/topic238.htm ) affects first the skin, then the central and peripheral nervous systems and intestinal tract. If allowed to progress without treatment, biotin deficiency can be serious.
Because biotin is an essential nutrient in almost all organisms--deer, squirrels, mice, and birds--browsing in avidin-corn fields may also be affected, as might plants, earthworms, and soil microorganisms. (In view of its toxic potential, some researchers are exploring its possible use as a broad-spectrum biopesticide.)
Hormones
Hormones are of particular concern because they can produce substantial
physiological effects in minute doses. Higher than normal levels of
human growth hormone, for example, can cause giantism in children and
acromegaly (overgrowth of bone and connective tissue associated with
reduced life expectancy) in adults.
Hormones are often developed as drugs and some are being developed in pharm plants. For example, human growth hormone, used to treat hypopituitary dwarfism in children, has been produced in transgenic tobacco. Some chemicals may mimic hormones and thereby disrupt endocrine function.
Allergens
Substances that can induce an allergic response are called allergens.
Proteins that elicit immune responses upon ingestion in food are called
food allergens and adding new proteins to food crops via genetic
engineering may suddenly render familiar food dangerous to sensitive
populations. Most proteins do not act as food allergens in humans, but
the relatively few that do can be very dangerous. Proteins can also
elicit immune responses if injected.
Plant-derived pharmaceutical and industrial proteins have the potential to cause unintended immune or sensitization responses in people who might unknowingly consume them as well as in patients treated with them. Plants modify the proteins they produce differently than do mammals and other organisms, and these modifications may affect characteristics related to allergenicity.
Routes of exposure to
people and livestock-the food and feed system
Since most pharm and industrial plants are also the crops that provide
food for people and feed for livestock, a major concern is the
contamination of the food and feed supplies. Pharm and industrial
plants have two major routes into the food and feed system: seed mixing
and pollen flow.
Seed mixing
Physical mixing of seeds can occur during seed production, on the farm
as a result of using the same machinery to plant or harvest both food
crops and pharm and industrial crops, during seed storage or transport,
or at the grain elevator or mill.
Pollen flow
Pollen flow is a more indirect way of introducing new genes into food.
Wind-borne pollen from corn, currently the most popular pharm and
industrial crop, can travel more than 50 yards, making possible
fertilization of nearby corn, intended for food, by pharm or industrial
plants. As a result, unsuspecting farmers who did not plant pharm corn
could nevertheless wind up with food and feed crops contaminated with
drugs, harvest them, and offer them for sale to mills. If seed corn is
contaminated with drug genes, farmers could unknowingly plant food and
feed corn containing biologically active proteins.
Pollen flow is an even wider route of exposure when plants like canola are used as pharm or industrial crops. Reportedly, canola pollen can spread as far as 15 miles from a parent plant and can not only fertilize other canola plants, but other crop plants (including turnip, Chinese cabbage, rutabaga and fodder rape) as well.
In situations where farmers save harvested seed to plant the next growing season, the contaminating genes and gene products may persist year after year.
Routes of exposure to the environment
Novel pharm and industrial substances have many routes to the environment. Since genetic engineers often cannot completely confine expression of new genes to particular tissues, pharm and industrial proteins will probably be produced throughout the plants. As discussed above, most of the pharm and industrial genes will be carried, and sometimes expressed, in pollen.
Grazing wildlife
Even if all the pollen, as well as the seeds and other plant material,
associated with every pharm and industrial crop remained within the
confines of the fields in which they were planted, wildlife could still
be exposed. As anyone who has attempted to keep deer out of a vegetable
garden or birds from fruit trees can attest, animal consumption of
field crops is essentially unavoidable.
Pollinators,
herbivorous insects, and soil inhabitants
Pollinators and herbivorous insects will undoubtedly frequent pharm and
industrial crop fields as well. Microbes and other animals present in
the soils of pharm and industrial crop fields will also be exposed to
the compounds produced in these plants via a process scientists refer
to as "rhizosecretion" (the exudation of substances from plant roots)
or when the agricultural byproducts of these crops are plowed back into
the earth to "dispose" of them through composting.
Weedy relatives
Although corn and soybeans do not have wild and weedy relatives in the
United States, canola and other important plants do. Canola pollen flow
could create a wild mustard weed capable of producing a pharm or
industrial compound, and such a weed would likely need little human
intervention, as compared to a crop plant, to perpetuate itself. Pharm
and industrial canola crops thereby threaten not only human food and
animal feed supplies but also the greater environment with exposure to
biologically active compounds.
Bioaccumulation
Some biopharmaceuticals may have physiochemical properties that could
make them persist in the environment or cause them to accumulate in
living organisms, dramatically increasing their potential to
contaminate ecosystems and their capacity to eventually make their way
into the human and farm animal food chains.
POLICY RECOMMENDATIONS
Pharm crops should be tightly regulated to protect against their risks to human health, the food supply, and the environment. Addressing these risks is also essential to the advancement of the technology—even one discovery of a food product contaminated with engineered drugs could hobble the technology, if not stop it in its tracks.
Under the federal framework for oversight of biotechnology products, the US Department of Agriculture (USDA) and the Food and Drug Administration (FDA) have primary responsibility for regulating pharm crops. The USDA oversees the environmental phases of pharm-crop production while the FDA steps in to regulate drug production and purity, clinical testing, and commercialization.
Those agencies have begun efforts to strengthen oversight of pharm crops, but it is a difficult task. Among other challenges, the regulatory system for pharm crops, like other parts of the federal biotechnology framework, was cobbled together from statutes originally enacted for other purposes. As a result, the current system is not appropriately tailored to pharm crops and therefore does not adequately protect against their risks.
As the centerpiece of new regulation, UCS has urged the USDA and FDA to take the following steps to ensure that the food supply is completely protected against contamination from pharm crops:
1. USDA and FDA should jointly set zero contamination of the food supply as the goal of the agencies’ pharm-crop policy.
Exposing consumers to drugs though food crops is an unacceptable risk to human health. In addition, the discovery of drugs in food items would cause momentous and costly disruptions in the food system. To guard against these serious consequences, USDA and FDA should work together to set zero contamination of the food supply as the goal of the agencies’ pharm-crop policy.
2. USDA and FDA should establish a public scientific advisory committee on pharm crops to consider and advise the agencies on the full range of measures available to meet the goal of zero contamination of the food supply.
To determine which measures—or combination of measures—can achieve a zero-contamination goal, USDA and FDA should convene a panel of experts. The agencies should charge the committee with defining and evaluating all available measures and approaches, including at a minimum the ones listed below, for their contribution to preventing contamination of the food supply.
Potential measures include:
The USDA/FDA pharm-crop advisory committee should deliberate in public. Its members should be selected for their expertise in relevant scientific disciplines and crop production. The panel should be balanced to include representatives from academia, the food and pharm-crop industries, consumer and environmental organizations, and organic and conventional commodity crop grower groups. The committee’s report should be written by its members and made public in a timely fashion.
3. USDA and FDA should use the advisory committee’s report to devise regulatory requirements to be imposed on growers, handlers, and transporters of pharm crops.
Once the government has the results of the committee’s work, it should evaluate the cost and feasibility of adopting the options or combinations of options that meet the goal of zero contamination of the food supply. Once it has selected the appropriate measures, the government should impose them as mandatory conditions on the field testing and commercial growth of pharm crops.
4. USDA and FDA should impose a moratorium on field tests and commercial production of engineered pharm crops until they have convened the scientific advisory committee and established a regime that the scientific community believes will assure the goal of zero contamination of the food supply.
The pharm-crop industry is
already struggling in the wake of previous contamination episodes: the
StarLink Bt-corn contamination of food products in 2000 and ProdiGene
Company’s mixing of pharm corn with soybeans at a grain elevator in
2002. Too much is at stake to allow more such incidents, which remain
possible as long as pharm crops are grown without adequate confinement.
To avoid a “StarLink with drug genes,” USDA and FDA should impose a
moratorium on field tests and commercial production of engineered pharm
crops. That delay should last until they have convened the scientific
advisory committee and established a regime that the scientific
community believes will assure the goal of zero contamination of the
food supply.
SUMMARY
Pharm and industrial crops
represent a new wave of biotechnology
crops different from the herbicide-tolerant and Bt crops that have
dominated the scene until now. The promised benefits (new and cheaper
drugs) could be important to many consumers. At the same time, these
crops pose obvious and important risks of contamination of the food
supply and the environment with non-food substances. It is vital to
regulate this emerging industry so that its benefits can be obtained,
without undue risks to human and animal health and the environment.
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