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Article

Safety and Public Acceptance of Transgenic Products

Dep. of Soil and Crop Sciences, Colorado State University, Fort Collins, CO 80523-1170

^* Corresponding author (Patrick.Byrne{at}ColoState.Edu)

In this article, the terms transgenic, genetically engineered, and genetically modified are used synonymously to mean organisms in which genetic material has been introduced through recombinant DNA technology.

	ABSTRACT

TOP NOTES ABSTRACT INTRODUCTION SUMMARY AND CONCLUSIONS REFERENCES

 
Public acceptance of transgenic (genetically engineered, GE) products is influenced by the perception of direct or indirect risks and benefits and the credibility of regulatory agencies that evaluate food and environmental safety. In North America acceptance of GE foods is holding steady, while knowledge about them remains low. Development of transgenic foods with improved nutritional properties or other quality factors will likely be better received than products that primarily benefit the grower or developer of the product. There is continuing unease about biopharming and the association, by some members of the public, of GE crops with corporate agriculture. Several recent reports have reviewed the U.S. regulatory system for transgenic crops and called for a more coordinated and transparent process that allows for greater public participation. For society to benefit from GE crops, we must move away from the polarized positions that have defined the transgenic debate in the past, to positions of mutual respect that allow a rational discussion of the technology's merits and risks.

Abbreviations: Bt, Bacillus thuringiensis • EPA, U.S. Environmental Protection Agency • FDA, U.S. Food and Drug Administration • GE, genetically engineered • GM, genetically modified • GMO, genetically modified organism • USDA, U.S. Department of Agriculture

	INTRODUCTION

TOP NOTES ABSTRACT INTRODUCTION SUMMARY AND CONCLUSIONS REFERENCES

 
GIVEN THE AMOUNT of published data, analysis, and opinions on the public acceptance and safety of transgenic crops, I will not attempt to cover these topics in depth here. Rather, my observations will highlight a few areas that I find particularly significant, based on several years of experience with an agricultural biotechnology outreach program.

One of my most memorable outreach experiences has been serving on a technical advisory committee in Boulder County, Colorado, to recommend policies for growing genetically engineered (GE) crops on county-owned land (Byrne and Fromherz, 2003). The 10 committee members were from a variety of occupations and displayed a broad range of attitudes toward GE crops. The committee included two "extremists," one at each end of the continuum. One of these members advocated nothing less than a complete ban on GE crops, while the other would not accept any restrictions on their use. During the 18 mo that the committee met, while most members engaged in give and take on the complex issues surrounding transgenic varieties, these two members never budged from their initial positions. In fact, one of them declared that no matter what he learned about GE crops, he would never change his mind about them. The result was that the extremist members did not contribute to the work of the committee, which was to craft a compromise policy that addressed valid concerns in a rational and fair-minded way (Byrne and Fromherz, 2003). This experience reinforced my belief that the zealous "pro" and "con" viewpoints that tend to dominate the public debate on transgenic crops interfere with the process of reaching reasonable decisions on how to benefit from GE crops while avoiding their pitfalls.

Public Knowledge and Attitudes About GE Foods
Looking at Hollywood's view of genetic engineering, one must conclude that the technology is a terrifying development. The films "Spider-Man," "The X Files," "Frankenfish," and "Corn" all involve the consequences of genetically modified organisms (GMO) that escape from the laboratory or cultivation as key ingredients in the plot. In the remake of "The Manchurian Candidate," the evil brainwasher started his career as a genetic engineer of tomatoes (Lycopersicon esculentum Mill.). Although the science behind these films is fuzzy, if not downright ludicrous, the impression presented is that modifying DNA is extremely risky and will inevitably lead to disaster. Images and innuendos presented by Hollywood can be especially persuasive for topics with limited public understanding, which certainly applies to genetic engineering.

Recent surveys report what many of us can state anecdotally, that American consumers' knowledge of GE food is low. For example, only 24% (Pew Initiative on Food and Biotechnology, 2003) and 31% (Hallman et al., 2004) of respondents believed that they had eaten GE foods, despite the fact that GE ingredients are present in 60 to 70% of supermarket products in the U.S. (Genetically Engineered Organisms Public Issues Education Project, 2004). Only 9% of respondents knew that the following statement was incorrect: "Ordinary tomatoes do not contain genes while GM tomatoes do" (Hallman et al., 2004). Forty-two percent believed that tomatoes engineered with catfish genes would probably taste fishy (Hallman et al., 2004).

Opinions about the safety of GE foods appear to be evenly split. In the survey by the Pew Initiative on Food and Biotechnology, 27% of U.S. consumers agreed that GE foods are basically safe, while 25% disagreed (Pew Initiative on Food and Biotechnology, 2003). A similar question in the study by Hallman et al. (2004) provided nearly identical results, with 27% approval of plant-based GE products and 23% disapproval (Hallman et al., 2004). It is noteworthy that nearly half the respondents in both surveys (48 and 49%, respectively) were either uncertain or neutral. In the Pew survey, when respondents were told that more than half of supermarket products involve some form of biotechnology or genetic engineering, opinions of food safety improved: 44% agreed that GE foods were safe, while 20% disagreed. This result provides at least some support for the regulatory process; if GE foods have been approved for sale, then almost half of consumers believe they are safe to eat.

For the record, a recent analysis of the safety of GE foods confirmed that no negative health effects due to GE foods have been documented in humans (National Research Council and Institute of Medicine, 2004). However, the report stated that unintended effects can arise from all forms of plant improvement, and therefore, that appropriate safety assessments are necessary.

Consumers are far more comfortable with genetic engineering of plants compared to modification of other organisms. On a scale of 1 to 10 (1 = very uncomfortable to 10 = very comfortable), respondents rated their comfort level with engineering of plants at 6, microbes at 4.2, animals for food at 3.8, insects at 3.6, animals for other purposes at 2.2, and humans at 1.4 (Pew Initiative on Food and Biotechnology, 2003).

Public acceptance of GE foods varies dramatically among countries. Curtis et al. (2004) considered consumers in the USA and Canada to be more or less neutral, based on their willingness to pay for or to avoid GE products. Western European and Japanese consumers tend to believe that the risks of GE foods outweigh the benefits; consumers in those countries stated that they would purchase GE foods only if they were offered at discounts of up to 50% (Curtis et al., 2004). In contrast, in China and Colombia the benefits of increased food availability and improved nutritional properties were perceived to outweigh the risks. Chinese consumers reported they were willing to pay a premium of 16 to 38% for certain GE traits (Li et al., 2002). The factors regarded as most important by Curtis et al. (2004) in determining consumer opinions were trust in government, attitudes toward science, and the nature of media coverage.

There is a very broad and deep literature on risk perception and communication (e.g., National Research Council, 1989; Sandman, 1993; Slovic, 2000). Many of the factors affecting perception of risk (Ropeik, 2004) are relevant to GE foods. Some of these factors and their rationales are as follows:

1. Natural vs. man-made: Human-generated risks elicit greater fear than natural risks.
   
2. Novelty: New technologies cause greater concern than those that have been around for a while.
   
3. Choice: If one can choose to avoid a risk, such as by utilizing information on GE food labels, it seems less dangerous.
   
4. Trust: The less trust there is in the people or institutions responsible for the risk, the more frightening it appears.
   
5. Risk–benefit trade-off: If a significant benefit is perceived from a technology, then the associated risk is felt to be smaller than if the benefit is thought to be small or nonexistent.
   

This last factor is extremely important and, I believe, has the power to trump the other factors. What, then, are the applications of plant genetic engineering that will be generally perceived to bring benefits to consumers or to society as a whole?

"Next Generation" GE Crops
Much has been written about the array of benefits that await consumers through transgenic technology (Dunwell, 1999). Although many nutritional enhancements have been proposed and researched, only a few seem to be moving toward commercialization. The most prominent of these is "Golden Rice" (Oryza sativa L.) (Ye et al., 2000), which is designed to alleviate vitamin A deficiencies and symbolizes transgenic technology's promise to address malnutrition in developing countries. Although heavily publicized by the biotechnology industry, progress toward field testing and local adaptation of the rice has been slow for a variety of reasons (Potrykus, 2001), and its eventual impact on nutritional status of the poor is uncertain. A "Golden Rice Humanitarian Board" has been established to guide further development and diffusion of the technology, and recent progress in improving Golden Rice's nutritional content is encouraging (Paine et al., 2005).

Producing oilseed crops with healthier or higher quality oil profiles is another way in which genetic engineering may benefit consumers. Lipid biochemical pathways in seeds are well characterized, many of the genes involved have been cloned, and the health benefits of specific classes of lipids have been established (Burton et al., 2004). All of these factors would seem to favor transgenic approaches. However, there are alternative, nontransgenic methods for achieving altered oil profiles, namely induced mutation and identification of naturally occurring variations (Burton et al., 2004). Therefore, except for specific lipid profiles not attainable by other methods, development of GE cultivars may not be the most cost-effective strategy, when the costs of the regulatory process are included.

Crops tolerant to drought stress are likely to be recognized as benefiting society as a whole, given the increasing demands for limited water supplies and recent memories of prolonged droughts in many parts of the world. As an example of the research underway in this area, three versions of experimental transgenic drought tolerant wheat (Triticum aestivum L.) lines have been field tested or will soon undergo such testing (Abebe et al., 2003; Bahieldin et al., 2005; Pellegrineschi et al., 2004).

Not all "next generation" GE crops are perceived as providing societal benefits. For example, "biopharm" crops, which are engineered to produce pharmaceutical proteins and have reached the field testing stage for some applications, have been greeted with more anxiety than enthusiasm (Andow et al., 2004; Colorado Institute of Public Policy, 2004; Freese, 2002). A significant difference in the response to biopharming is that some of the groups raising concerns, including farmers, food companies, and nutritionists, have been generally supportive of agricultural biotechnology in the past. To avoid a backlash against crop biotechnology in general, companies and regulators will need to proceed very cautiously with biopharming.

Broader Concerns About the Current Agricultural System
Something I've observed in dealing with the public is that unease over GE crops is not just about transgenic technology, but reflects wider concerns about an unsustainable agricultural system. In a letter to Science, Freckleton et al. (2004) expressed this sentiment well: "The debate over GM crops is just one small component of a much wider debate that needs to take place on how to develop a sustainable rural landscape for the future." Part of that debate needs to focus on the goals of our agricultural system, whether they should focus only on food production, or also include issues related to soil and water conservation, wildlife management, rural economic viability, and pleasing landscapes.

The complexities of agroecosystems are such that introducing new technology into a farming system can have unintended results. An instructive example involves sandhill crane (Grus canadensis L.) migration through the Platte River Valley of central Nebraska (Krapu et al., 2004). Each spring about 80% of North American sandhill cranes stop along the Platte and North Platte Rivers, where waste corn (Zea mays L.) accounts for over 90% of their diet. Improvements in corn harvest technology have resulted in less waste corn in the fields, accompanied by a 46% decline in fat content of the cranes since 1978. Improved profitability of soybeans, at least partly due to glyphosate tolerance, has resulted in increased soybean production and less corn production in the area. Unfortunately, soybeans are a poor source of energy for the cranes. Weed seeds, a secondary nutrient source, have also been reduced by herbicide tolerant crops. Clearly, GE crops alone are not responsible for declining food availability for sandhill cranes. However, they are part of a system that can significantly impact wildlife populations when applied over large areas. At a minimum, additional monitoring and evaluation of these altered systems are needed.

Concerns with GE Crop Regulation
Most consumers do not have the time, interest, or technical background to evaluate the food and environmental safety of GE crops. Rather, they depend on an appropriate regulatory system to investigate the issues in a rigorous and unbiased manner. Therefore, ensuring the existence of a credible regulatory process is the single most important factor in gaining public trust. Three federal agencies regulate distinct aspects of GE crops in the U.S.: the Department of Agriculture (USDA), the Environmental Protection Agency (EPA), and the Food and Drug Administration (FDA). Among the shortcomzings of the current regulatory system are the following (Committee on Genetically Modified Pest-Protected Plants, 2000; Pew Initiative on Food and Biotechnology, 2004):

1. The system operates in a reactive rather than a proactive mode, and has had difficulty keeping up with the technology and public concerns. An example of this type of shortcoming is the evolving regulatory process for biopharmaceuticals.
   
2. Authority is fragmented among three agencies, leading to concerns that some novel transgenic applications will not fall under the authority of any agency.
   
3. There is a lack of transparency, that is, information on regulatory decisions is not readily available to the public.
   
4. There are few opportunities for public participation.
   

The Pew Initiative on Food and Biotechnology recently published an extensive review of the issues surrounding the regulation of GE plants and animals (Pew Initiative on Food and Biotechnology, 2004). To their credit, the authors did not prescribe a set of measures to improve the system, but instead listed the issues that need to be addressed. A highly selective subset of their issues for environmental safety and food and feed safetyfollows.

Questions that are pertinent for regulation of environmental safety

1. Should USDA evaluate overall environmental risk of transgenic crops? Currently, their authority is limited to plant pest or noxious weed risk.
   
2. Should USDA have post-market authority, for example, to require reporting or monitoring of a product after its commercialization?
   
3. Should EPA have direct authority over grower compliance with planting restrictions, e.g., refuges planted in conjunction with Bt corn and cotton (Gossypium hirsutum L.)? The EPA's current authority applies to the seed companies, not to growers.
   
4. Should EPA play a role in regulation of plant-made pharmaceuticals? At present, EPA does not review environmental effects of biopharm crops.
   

Questions that are pertinent for regulation of food and feed safety

1. Should premarket notification of FDA be required before a food is commercialized? Such notification is not mandatory at present, although it is routinely done.
   
2. Should FDA add an affirmative finding of safety to the transgenic foods it reviews? Currently, FDA informs the developer that it has "no further questions" about the safety of the product, which is a very passive statement of food safety.
   
3. Should FDA apply food additive provisions to GE food, or to some classes of GE foods? Declaring food additive status would trigger a formal, in-depth safety review of the product.
   
4. Should there be a mechanism for early food safety reviews to minimize risks of unapproved crops undergoing field testing?
   

Hope for the Future
Several recent developments provide hope that the U.S. regulatory system may be improved and that future products of agricultural biotechnology will avoid some of the safety issues that have affected earlier products. One of these developments is USDA's intention to prepare an Environmental Impact Statement of its regulation of GMOs (Animal and Plant Health Inspection Service, 2004). Among the topics that may be evaluated are an expansion of USDA's authority to regulate additional types of transgenic organisms; establishment of a tiered system for risk-based regulation; allowance for low-level adventitious presence of controlled products in the food/feed supply; and development of a mechanism for regulation of biopharm crops grown in confined conditions.

Another positive development is the recent doubling of funding for the Biotechnology Risk Assessment Grants Program of USDA-CSREES (www.csrees.usda.gov/fo/fundview.cfm?fonum=1075; verified 27 Aug. 2005). This program is directly targeted to produce information useful to federal regulators of agricultural biotechnology. Among the funded projects are those that address pollen dispersal in corn, wheat, sunflower (Helianthus annuus L.), and creeping bentgrass (Agrostis stolonifera L.); fitness effects of transgenes in wild plant populations; biosafety of chloroplast transgenes; and transgene confinement strategies in trees. Results of these projects will help answer questions about the environmental effects of GE crops, presumably leading to more informed decisions about their commercialization.

Finally, two publications with similar themes address the need to consider safety issues at the earliest stages of GE product conceptualization. Kapuscinski et al. (2003) describe a "safety first" approach, involving public–private partnerships for "transparent development of proactive safety standards that anticipate and resolve safety issues as far upstream of commercialization as possible." The authors are optimistic about such a process because it should benefit multiple stakeholders, including biotechnology companies and those concerned with food and environmental safety. Doering (2004) also calls for more attention during the design phase of GE crops to ensure that they meet national goals for food safety and agricultural sustainability. Examples of GE crop design that incorporate safety concerns are more precise gene insertion, better control of gene expression, and elimination of unnecessary DNA sequences from the inserted gene. Crops that address sustainability goals include those that use chemicals, energy, and water more efficiently, or that are planted for phytoremediation of contaminated soils.

	SUMMARY AND CONCLUSIONS

TOP NOTES ABSTRACT INTRODUCTION SUMMARY AND CONCLUSIONS REFERENCES

 
In summary, public acceptance of GE foods in North America is holding steady, while knowledge of these foods remains low. Consumers will likely respond positively to products with improved nutritional quality, and at least a few such products may be introduced in the next several years. There is continuing unease about biopharming and the association of GE crops with corporate, and/or unsustainable agriculture. Improvements to the regulatory system are needed to address valid concerns and bolster public confidence in GE foods. For society to benefit from GE crops, the most important step forward is to move away from the polarized positions that have defined the transgenic debate so far, to positions of mutual respect that will allow a rational discussion of both the merits and risks of the technology.

	ACKNOWLEDGMENTS

 
The author acknowledges support from Colorado State University Cooperative Extension and from a USDA-CSREES-IFAFS grant related to this topic. He has benefited from discussions with many colleagues, especially Dr. Sarah Ward and Ms. Judy Harrington of Colorado State University.

	NOTES

TOP NOTES ABSTRACT INTRODUCTION SUMMARY AND CONCLUSIONS REFERENCES

 
Based on a presentation at the symposium "Transgenics in Plant Breeding: Do They Have a Future?", American Society of Agronomy annual meeting, 31 Oct. to 4 Nov. 2004, Seattle, WA.

Received for publication February 17, 2005.

	REFERENCES

TOP NOTES ABSTRACT INTRODUCTION SUMMARY AND CONCLUSIONS REFERENCES

 

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This Article Abstract Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in ISI Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via ISI Web of Science (3) Citing Articles via Google Scholar Google Scholar Articles by Byrne, P. F. Search for Related Content PubMed Articles by Byrne, P. F. Agricola Articles by Byrne, P. F. Related Collections Sustainable Agriculture Crop Genetics Ecological Risk Assessment