Genetically Engineered Crops: Experiences and Prospects
by the Committee on Genetically Engineered Crops: Past Experience and Future Prospects; Board on Agriculture and Natural Resources; Division on Earth and Life Studies; National Academies of Sciences, Engineering, and Medicine
Available for free at http://www.nap.edu/catalog/23395/genetically-engineered-crops-experiences-and-prospects
Much has been made of the results of this meta-assessment of experiences to date with and prospects for genetically engineered crops. While the commentary has largely been spun around the report’s conclusion that GE crops are generally “safe”, the report also identifies many problems and unknowns with regard to GE crops. While acknowledging at the outset that the authors’ conclusions are, in sum, positive with regard to GE crops, I read through a lot of the lengthy report and compiled a number of the authors’ concerns or questions, listed below.
Limitations of the report
I have heard people comment that the science is support of genetic engineering in agriculture is as solid as is climate science in affirming the reality of human-induced climate change. And that this report is another confirmation of that “fact”. Not so.
First off, the comparison makes no sense. Climate change is a yes or no kind of fact, and virtually every accredited scientist on the planet with expertise in this area confirms that, yes, it is happening. GE is different thing altogether. It is an optional technology with pros and cons. It makes no sense to say that, as a whole, it is “good” or “bad”. As the authors of this report say, “sweeping statements about GE crops [for or against] are problematic because issues related to them are multidimensional.” The report makes it clear that there are benefits and/or costs and these are dependent on particular circumstances that include multiple factors, such as farm size, location, weather conditions, socioeconomic conditions, environmental factors and so on.
The report generally supports the notion of GE crops but it does not support them holus-bolus. It all depends, and there is plenty of debate among the scientific community about the pros and cons of various applications in different circumstances.
The second thing to note is what an analysis of this sort leaves out. A full cost benefit analysis of GE crops would have to compare their use to various other approaches. What is the opportunity cost, the loss of potential gain from other alternatives when one alternative is chosen”? Billions have been invested in GE crop research and commercialization. What would the results have been if that investment had been put into other technologies and approaches? And to what extent does the overall structure of the global food and agriculture system influence, or is influenced by, this set of technologies or that?
The authors say, for instance,
“We received a number of broad comments that asked us to examine and make judgments about the merits of technology-intensive agriculture compared with more agroecological approaches. That would be an important comparison but was beyond the scope of the specific task given to the committee.”
Whether other approaches to agriculture, such as agroecology, holistic resource management, organic techniques would give equal or better results compared to GE, under various conditions, is beyond the scope of the report. This is not to say that the analysis is not a good one, rather that it has limitations and cannot be considered any kind of final word on whether GE crops are “good” or “bad”.
It should also be pointed out that only two traits—insect resistance and herbicide resistance—had been genetically engineered into about 10 crop species and were in widespread use in 2015. GE crops are used on about 12% of cropland worldwide.
Social and Economic Impacts
The report indicates that GE crops should not be considered a panacea. Broader issues will determine the success of the agrifood system:
“The social and economic effects of GE crops depend on the fit of the GE trait and the plant variety to the farm environment and the quality and cost of the GE seeds. GE crops have benefited many farmers on all scales, but genetic engineering alone cannot address the wide variety of complex challenges that face farmers, especially smallholders.”
The report also states that decisions around GE technology go beyond the sphere of science and require complex decisions at all levels of society:
“In addition to issues of product safety, socioeconomic issues that go beyond product safety are technology-governance issues that should be addressed by policy-makers, the private sector, and the public in a way that considers competing interests of various stakeholders and inherent tradeoffs.”
Isn’t the whole point of GE crops to improve crop yield? Surprisingly, the report actually questions whether it can be said that GE crops have resulted in an overall crop yield increase, compared to conventional breeding.
“The nation-wide data on maize, cotton, or soybean in the United States do not show a significant signature of genetic-engineering technology on the rate of yield increase.”
Individual farmers have obtained yield increases, yes, but it is not even certain that GE crops have been responsible for increasing yields, at least in the United States. Extraordinary.
“There is disagreement among researchers about how much GE traits can increase yields compared with conventional breeding. In addition to assessing detailed surveys and experiments comparing GE with non-GE crop yields, the committee examined changes over time in overall yield per hectare of maize, soybean, and cotton reported by the U.S. Department of Agriculture (USDA) before, during, and after the switch from conventional to GE varieties of these crops. No significant change in the rate at which crop yields increase could be discerned from the data. Although the sum of experimental evidence indicates that GE traits are contributing to actual yield increases, there is no evidence from USDA data that they have substantially increased the rate at which U.S. agriculture is increasing yields.”
“The quantitative contribution of GE crop traits themselves to yield in experimental plots was sometimes difficult to determine because the GE and non-GE varieties could differ in other yield-associated traits. In surveys on yield and insecticide and herbicide use in farmer fields, the different adoption rates of GE crops by farmers who had different land quality and financial resources confounded some results. There is a need for improved survey and experimental approaches that disentangle the effects of the GE trait itself from other factors that affect yield.”
And apparently, farmers are adopting GE crops without clear evidence of economic benefit. Are GE crops just a fad or trend?
“In situations in which farmers have adopted GE crops, especially those with herbicide resistance, the committee finds that nonmonetary considerations are probably driving adoption of GE crops despite the absence of a readily identifiable economic benefit related to their production.”
One claim in favour of GE crops is that their adoption would result in lower usage of herbicides. The report says this was the case at first, but decreased usage has not been sustained:
“The use of HR [herbicide-resistant] crops sometimes initially correlated with decreases in total amount of herbicide applied per hectare of crop per year, but the decreases have not generally been sustained. However, such simple determination of whether total kilograms of herbicide used per hectare per year has gone up or down is not useful for assessing changes in human or environmental risks.”
“With regard to changes in the amount of herbicide used since the commercialization of GE crops, the committee found that there were decreases in total kilograms of herbicide applied per hectare of crop per year when herbicide-resistant crops were first adopted, but the decreases have not generally been sustained.”
Also, an overall decrease in herbicide use may be meaningless; the overall risks associated with different herbicides are more relevant. Claims of decreased pesticide use are misleading the public.
“Although total kilograms of herbicide applied per hectare is often referred to in assessments of changes in risks to the environment or to human health due to GE crops, this measurement is uninformative because the environmental and health hazards of different herbicides vary, so the relationship between kilograms of herbicide applied per hectare and risk is poor.”
“Recommendation: Because of the difference in toxicity in the various chemicals used, researchers should be discouraged from publishing data that simply compare total kilograms of herbicide used per hectare per year because such data can mislead readers.”
The use of glyphosate has skyrocketed with the introduction of GE HR crops. Originally considered safer than other herbicides, this is no longer clear:
“There is disagreement among expert committees on the potential health harm that could be caused by the use of glyphosate on GE crops and in other applications. In 2015, the International Agency for Research on Cancer (IARC) of the World Health Organization (WHO) issued a monograph in which it changed its classification of glyphosate from Group 2B (possibly carcinogenic to humans) to Group 2A (probably carcinogenic to humans).” [To be fair, other studies cited downplay the glyphosate-cancer connection.]
It appears that the adoption of GE crops may have resulted in both the decrease in crop diversity and the use of crop rotation.
“Since 1987, there has been a decrease in diversity of crops grown in the United States—particularly in the Midwest—and a decrease in frequency of rotation of crops. However, the committee could not find studies that tested for a cause-and-effect relationship between the use of GE crops and this pattern.”
“For the United States and Brazil, it is clear that where GE varieties have been widely adopted by farmers, the supply of non-GE varieties has declined, although they have not disappeared. There is uncertainty about the rate of progression of that trend in the United States, Brazil, and other countries. More research is needed to monitor and understand changes in variety diversity and availability.”
While it may be possible to make a general statement that GE crops have not been shown to increase environmental problems overall, the difficulty in assessing environmental impacts make it difficult to be definitive about such a conclusion. Plus, long term implications of the adoption of GE crops for the environment remains unclear.
“Overall, the committee found no conclusive evidence of cause-and-effect relationships between GE crops and environmental problems. However, the complex nature of assessing long-term environmental changes often made it difficult to reach definitive conclusions. That is illustrated by the case of the decline in overwintering monarch butterfly populations. Studies and analyses of monarch dynamics reported as of March 2016 have not shown that suppression of milkweed by glyphosate is the cause of monarch decline. However, there is as yet no consensus among researchers that increased glyphosate use is not at all associated with decreased monarch populations.”
“If short-term profit goals lead to the expansion of crops into previously unmanaged habitats or to the unsustainable use of agricultural lands, that could result in decreased global biodiversity and undesirable variation in crop yields. Certainly, deployment of new crops in ways that increase the long-term economic sustainability of resource-poor farmers could result in improvement in environmental sustainability.”
GE Crop “drift”
The “drift” of GE seeds into the fields of non-GE farmers has been a hot topic in the news, including in Saskatchewan. This remains an area of confusion.
“In the case of GE crops, adventitious presence is the unintended and accidental presence of low levels of GE traits in seeds, grains, or foods. Preventing adventitious presence is valuable for societal reasons because farmers want the freedom to decide what crops to grow on the basis of their skills, resources, and market opportunities and for economic reasons because markets are differentiated and organic and nonorganic, non-GE crops command a price premium. Questions about who is economically responsible for adventitious presence between farms remain unresolved in the United States. Strict private standards create an additional layer of complexity because producers may meet government guidelines for adventitious presence but fail to meet contract requirements set by private entities.”
Intellectual property and innovation
GE crops are virtually all proprietary, which has many implications for farmers. Is this a good thing or not?
“With regard to intellectual property, there is disagreement in the literature as to whether patents facilitate or hinder university-industry knowledge sharing, innovation, and the commercialization of useful goods. Whether a patent is applied to a non-GE or a GE crop, institutions with substantial legal and financial resources are capable of securing patent protections that limit access by small farmers, marketers, and plant breeders who lack resources to pay licensing fees or to mount legal challenges.”
“More research should be conducted to determine whether seed market concentration is affecting GE seed prices and, if so, whether the effects are beneficial or detrimental for farmers.”
“Research should be done on whether trait stacking (that is, including more than one GE trait in a variety) is leading to the sale of more expensive seeds than farmers need.”
“Investment in basic research and investment in crops that do not offer strong market returns for private firms should be increased. However, there is evidence that the portfolio of public institutions has shifted to mirror that of private firms more closely.”
Implications for small farmers
Much has been made of the potential of GE crops to “feed the world” and improve production in low-income countries. In these countries, most farms are very small, often subsistence farms in the 1-hectare range, that provide a way of life for about one third of humanity. Have GE crops helped this group, given that it requires farmers with few financial resources to purchase external inputs such as seeds, chemicals and fertilizers?
First of all, GE crops are mainly developed for large-scale commercial farms, not for the vast majority or small-scale farmers. The sample is so small it would be impossible to say GE is a positive for such small farmers:
“At the time that the committee’s report was written, only a few GE traits had been incorporated into crops, and Bt eggplant, the only GE crop that had been specifically developed to address the needs of small-scale, resource-poor farmers, was planted by fewer than 150 farmers worldwide. However, many such traits that were designed with small-scale producers or poor consumers in mind were in development in 2015.”
The costs of adopting GE crops, which are developed by private companies to increase their profits, may be beyond most small farmers:
“For resource-poor smallholders who want to grow GE crops, the cost of GE seed may limit adoption. In most situations, differential cost of GE and non-GE seed is a small fraction of total costs of production, although it may constitute a financial constraint because of limited access to credit. In addition, small-scale farmers may face a financial risk when purchasing a GE seed upfront because the crop might fail; this may be an important consideration for small-scale farmers.”
“Although GE crops have provided economic benefits to many small-scale farmers in the early years of adoption, enduring and widespread gains will depend on institutional support, such as access to credit, affordable inputs, extension services, and access to profitable local and global markets for the crops. Virus-resistant papaya is an example of a GE crop that is conducive to adoption by small-scale farmers because it addresses an agronomic problem but does not require concomitant purchase of such inputs as fertilizer or insecticides. GE plants with insect, virus, and fungus resistance and with drought tolerance were in development and could be useful to small-scale farmers if they are deployed in appropriate crops and varieties.”
The penetration of GE crops will depend on public supports, etc. However, public investment in agriculture research is decreasing”
“Genetic-engineering technology that is of most use to small-scale farmers or farmers of specialty crops will probably have to emerge from public-sector institutions or from public-private collaborations because current intellectual-property regimes do not offer incentives for private-sector firms to pursue research in those crops. However, growth in investment in public agricultural research in the United States has been declining since the 1960s and was almost $2 billion less than private-sector investment in 2009 (NRC, 2014). In developing countries, the situation regarding R&D investment is highly variable. In some countries, investment in public sector R&D has increased substantially; in others it has not. Furthermore, there has been a rise in development assistance focused on agriculture, including investment in genetic engineering. Decreases in support for the public sector may reduce the potential diffusion of new GE crop innovations.”
Do GE crops increase food security? Questionable, because food security is a very complex matter that is not the product of any one factor.
“The committee heard diverse opinions on the ability of GE crops to affect food security in the future. GE crops that have already been commercialized have the potential to protect yields in places where they have been introduced, but they do not have greater potential yield than non-GE counterparts. GE crops, like other technological advances in agriculture, are not able by themselves to address fully the wide variety of complex challenges that face smallholders. Such issues as soil fertility, integrated pest management, market development, storage, and extension services will all need to be addressed to improve crop productivity, decrease post-harvest losses, and increase food security. More important, it is critical to understand that even if a GE crop may improve productivity or nutritional quality, its ability to benefit intended stakeholders will depend on the social and economic contexts in which the technology is developed and diffused.”
“To contribute to alleviation of hunger in food-insecure populations on and off farms, more GE crops and crop traits will need to be developed in ways that increase potential yield and protect yield from biotic and abiotic stresses, and improve nutritional quality. Even if that is accomplished, the ability of GE crops to alleviate hunger will depend on the social and economic contexts in which the technology is developed and diffused.”