Food – Genetic Engineering
Did You Know?
Between 90 and 100% of U.S. corn, soy, cotton, canola, and sugar beet crops are now genetically engineered (GE).
Various studies of mice and rats fed GE food have shown increase incidents of cancer, infertility, irritation of the digestive tract, and liver and kidney disease.
Many GE corn crops were bred to produce natural insecticide. Due to natural resistance that insects have developed, new GE strains now contain 2 to 4 times the toxins contained in GE corn in the 1990s.
The amount of Bt toxin contained in GE corn is 19 times the conventional topical pesticide needed to target the same pests.
Since the 1990s when GE crops were first commercialized, U.S. pesticide per acre for soy has more than doubled.
The New Gene is the New Norm (and so are its consequences)
In 2017, 60% of the estimated 470,000 square miles of food, fiber, or fuel (ethanol) producing cropland in the U.S. was planted with genetically engineered (GE) seeds.1 The vast majority of this was in major “commodity” crops (canola, corn, cotton, and soy), though GE crops are beginning to make small inroads into produce sales, and even fish. For almost all Americans, they are impossible to avoid: you are eating them, or wearing them, or driving them – usually all three.
GE crops were considered science fiction, or at least novel, in the early 1990s. GE critics of that era now seem prescient for their warnings about the human health and environmental consequences of these new technologies.
State of the Gene Report
GE seed products began commercial sales in the U.S. in the 1990s. By 2019, many of the United States’ large commodity crops had one or more GE traits: 92% of corn acres; 94% of soybean acres; 98% of upland cotton acres; and 100% of canola acres.2 Since corn and soybean derivatives are ubiquitous in processed food, the majority of the U.S. population is ingesting GE crops, at least in small quantities.
By 2017, 100% of sugar beets were also GE.3 (In 2018, beets provided half of all the domestic sugar supply in the U.S. Domestic sugar products, including cane, accounted for 73% of total American consumption.)4
Due to loose laws, and regulatory agencies that critics consider held captive by special interests, the absence of mandatory labeling, and the large share of commodity crops grown for the world market, the U.S. leads the way in GE acreage. In 2017, 40% of all GE crop acreage in the world was in the U.S.5 Contrasting this is Europe, where the percentage of GE crops grown is negligible due to public suspicion.
GE products have also made small incursions into the U.S. produce market.6
• About 6/10ths of 1% of potatoes were GE in 2017. Brands include the INNATE® Russet Burbank, Ranger Russet, Atlantic, and Snowden lines.
• About 4/10ths of 1% of U.S. apples were expected to be GE by 2019. The original brand was Arctic Golden Apples, though this was expected to expand to Fuji and Granny Smith apples as well.
(Both GE apples and potatoes are engineered to eliminate browning when the produce is cut or bruised.)
• About 77% of Hawaiian papaya was GE in 2017. However, the vast majority of papaya consumed in the U.S. was imported, so only about 2% of papayas consumed overall in the U.S. in that year were GE.7
• About 6.5% of U.S. yellow crooked neck squash was GE in 2017.
(Both GE papaya and squash are engineered to be resistant to specific viruses.)
The majority of the commodity crops are engineered for two traits. The first is to be herbicide-tolerant (HT), with the most common herbicide being glyphosate (contained in the well-known product Roundup®). The second is to be resistant to certain insects because they contain proteins of bacillus thuringiensis (Bt), a natural pesticide derived from soil bacteria used by organic farmers because it is less toxic than conventional products. Most seeds on the market have both traits. The HT varieties were sold to farmers as a convenient way to save money when eliminating weeds. The Bt varieties were sold as a cheap and safe way to eliminate pests.
The health and environmental effects of these have become increasingly apparent.
• Health advocates stated that GE foods might alter the contents of food, with possible adverse reactions.
• Opponents of HT strains warned that weeds themselves would become resistant or immune to the herbicides that crops were designed to withstand, creating the need to use greater volumes of herbicides or different herbicides.
• Opponents also warned that insects would develop resistance to Bt.
• GE critics worried that the new technologies could disrupt ecosystems.
All predictions have been borne out.
Health problems have been linked to GE food. Causes may include the increased use of herbicides (and the residues left on food) in addition to the GE crops themselves.
• A French study conducted in 2009 showed that rats fed with 3 different varieties of GE corn (one that was glyphosate resistant, and two that included Bt pesticide) had a marked effect on liver and kidney health compared to controls after only 90 days on this diet.8
• Another French study released (which included two of the same scientists) in 2014 showed rats that ingested various levels of HT corn had pronounced levels of kidney and liver disease and tumor incidence compared to control rats that ate none.9 In male rats, kidney disease increased 67-133% depending on the percentage of GE corn in their diet. Liver disease increased 150-480%. Breast tumors in female mice increased 25-88%, in large part because the herbicide raised estrogen levels.
The most revealing finding from this study was that it largely used the same methodology Monsanto, the company that created the products, had used to gain regulatory approval. However, instead of observing the rats for only 90 days as was done in the Monsanto study, the French study ran for 2 years.
• A 2008 study by the Austrian health ministry also showed harmful effects to reproduction.10 Mice fed GE corn had fewer litters, (consequently) fewer total offspring, and more females with no offspring compared to mice fed conventional corn.
• Another long-term 2-year study of mice by an Italian team of scientists in 2008 revealed that female mice fed a diet of 14% GE soy had significant liver deterioration compared to control mice.11 This followed a study conducted by some of these same scientists a few years before showing that this same GE soy percentage could influence pancreatic metabolism in mice.
• Another Italian team of scientists found that very young and very old mice (which have weaker immune systems than mature adult mice) fed GE corn with Bt insecticide had weakened immune response.12
• The Bt toxin spliced into GE crops to make them resistant to insects has been shown to provoke potent immunological reactions when fed to mice.13
• At least 2 studies showed that mice fed with GE potatoes had increased incidence of digestive tract irritation.14
• Herbicide tolerant crops have been shown to be deficient in key mineral “micronutrients” that are essential for proper nutrition, including calcium, copper, iron, magnesium, manganese, nickel, and zinc.15 The uptake of nitrogen is also altered.
Another health problem some of these crops are likely to cause is the loss of an important indicator of food spoilage. As stated previously, GE apples and potatoes are now engineered to resist browning when cut or bruised. This common indicator is now masked by “counterfeit freshness.” However enhanced the food looks cosmetically, browning has been a time-tested way people have used to avoid food that might be spoiled or contaminated.
How to Avoid GE Food
Late in 2018, the U.S. Food & Drug Administration created a GE labeling standard. After almost 3 decades of controversy, the agency partially succumbed to consumer pressure to allow buyers clear notice of foods they might wish to avoid for ethical or nutritional reasons. However, the standards have been heavily criticized by consumer advocates.
1. Though nothing precludes immediate participation by food manufacturers, producers, and marketers, labeling is not required until 2022.
2. Most processed foods have derivatives of GE crops in their ingredients (e.g., corn, soy, or canola oil; soy protein; corn starch and sugar), but these ingredients will not have to be identified as GE because the original GE DNA is supposedly destroyed when manufacturing the derivatives.
3. Even when labeling is (finally) required, it may not even have to be in the form of a label. While the “Bioengineered” label is an option, it is not a mandate. An alternative will allow food manufacturers, producers, and marketers to use the QR code on the product. Consumers with smart phones can access information electronically. However, this option can lead to frustration if there is poor or no wireless service, or if the customer does not have a phone with a QR reader application.
4. The new labeling standards may exempt newer seed and food creation techniques that are similar but not identical to the strict definition of GE, such as synthetic biology.
Customers who want to avoid GE products have other options available.
• Look for the U.S. Department of Agriculture (USDA) Certified Organic and/or the “NON GMO VERIFIED” labels. Neither certification standard allows GE products.
• If you are looking at produce, look for the 5-digit PLU code decal. If the code has a “9” at the start, it designates organic. But if it has an “8,” it means it is GE. (A 4-digit code means the produce is conventional.
• Avoid products that boast their GE origins, including Arctic apples, INATE® potatoes, and Hawaiian papayas that are not organic. Also, fish eaters should avoid AquaBounty salmon when it comes to market.
Superweeds: Many GE strains were specifically bred to withstand the herbicide glyphosate (again, the main ingredient in Roundup®). It was convenient for farmers because they could easily use the herbicide on weeds without damaging their crops. Critics warned even before these seeds were sold commercially that the products would become obsolete. They feared some of the unwanted weeds would survive the herbicide treatments and pass the survival trait on to their descendants. They would become, in effect, “superweeds.”
This has happened with a seeming vengeance. In 1996, when GE soybeans resistant to herbicides were first introduced commercially, only a small percentage of soybean acreage harbored weeds resistant to the herbicide. By 2012, nearly all soybean acreage had resistant weeds.16 These weeds can grow so tall that they leave crops in their shadows, and they compete with crops for soil nutrients and water as well as sunlight. Depending on the species and location, superweeds can decrease corn yields 15 to 91% and soybean yields by 44 to 80%.17
In 2000, there were 2 species of weeds that were glyphosate resistant. By 2012, there were 13 resistant species.18 By then, 40% of Illinois farmers had encountered glyphosate-resistant weeds; in Georgia, it was 92%.19
Charts G1 and G2 show the increase in pesticide use per acre in U.S. corn and soy crops between 1995 (the year before GE commercial seeds were sold) and 2018.20 Corn pesticide use did decrease, but has soared back due to weed resistance. Soy pesticide use has more than doubled.
Industrial agriculture’s quicksand solutions include using even more glyphosate to compensate for resistance, and using other herbicides while breeding new varieties of crops that will tolerate them. These other herbicides include dicamba, 2,4-D, and mixtures of these with glyphosate.
Superpests: Unlike herbicide use in GE plants, which has increased since they were introduced, conventional insecticide use in corn and cotton has generally fallen by huge percentages per acre since Bt varieties were created.
On closer inspection, it is easy to see why. As example in one GE corn species, the amount of Bt toxin contained is 19 times the amount of conventional topical pesticide needed to target the same pests.21
It is also easy to see how insects have developed immunity. First-generation GE Bt cotton varieties only had one Bt toxin laced in their genes. Due to insect resistance, 2nd, and 3rd generation Bt varieties are being planted that have two or 3 different types of Bt toxins in them.22 Because of these “pyramided” traits, newer GE corn varieties can have 2 to 4 times more Bt toxins embedded in the plant than original varieties developed in the 1990s.23
Pesticide danger is magnified when you consider that the U.S. Department of Agriculture data reflected in the charts above does not measure the neonicotinoid insecticide that coats the GE seeds. This is a systemic toxin that permeates the plants’ tissue.
GE as Invasive Species: (When Seeds are Weeds) – GE crops have become so common in the U.S. that they have insinuated themselves into the greater environment. In some respect, GE crops and plants have taken on the role of invasive species that crowd out existing ones.
GE crops planted in specific areas do not remain rooted to their original location. They can spread to food supplies or the general environment in at least 4 ways.
1. Contaminated Seeds – Due to accidents and improper handling, GE seeds can become comingled with non-GE seeds and organic seeds.
2. Contaminated Food – Due to accidents and improper handling, GE crops and processed food such as corn flour can also become mixed with non-GE and organic products.
3. Contaminated Pollination – GE plants cross-pollinate with non-GE plants, passing on their genetic traits to the detriment of hapless farmers and consumers, as well as the general environment.
4. Unrestrained Migration of Plants – Seed cross-contamination, cross-pollination, and asexual development allow GE plants to escape from farms and test plots to other farms and into the natural landscape.
GE food is not only difficult to avoid in the average American diet, but it has affected the food supplies even for those intentionally trying to avoid them. A study as far back as 2004 showed that 50% of non-GE corn and 83% of non-GE canola had small rates of GE contamination.24 A 2014 survey of organic farmers revealed that a third of respondents had experienced economic losses from GE contamination.25
Documented incidents of contamination in the U.S., with accompanying economic losses to farmers and contamination of the environment, have piled up since at least the year 2000 for alfalfa, canola, corn, flax, papayas, rice, and wheat, as well as turf grass.
• Alfalfa – A strain of this forage crop has been bred to resist glyphosate. In 2013, an export shipment was canceled after it was determined to be this GE variety.26 A 2015 study showed that 27% of roadside stands of wild alfalfa in California, Oregon, and Washington contained transgenic plants.27
• Canola – Escaped GE-canola resistant to herbicides is growing rampant along the roadsides of North Dakota. Since it is the state’s procedure to spray roadsides with herbicide, the canola survives where other plants cannot. A study found 46% of highway sites had wild canola growing, and 86% of the plants had GE herbicide-resistant traits.28
Canola is particularly problematic since it is in the same species (and can cross pollinate with) some vegetable crops, including broccoli rabe, Chinese cabbage and Chinese Mustard, rutabaga, Siberian kale, and turnips, among others.
• Conventional Corn – In 2000, 300 food products were contaminated with a GE variety meant for animal feed and not human consumption because it might cause food allergies. Exports to Japan fell 44% and farmers suffered huge losses.29 In 2002, experimental corn bred to produce pharmaceutical drugs contaminated 500,000 bushels of soybeans that had to be destroyed.30 Between 2001 and 2004, a GE variety unapproved for U.S. cultivation was mistakenly distributed to farmers, resulting in the rejection of exports to Japan and the EU.31 In 2014, between $1 and $3 billion in export losses occurred when China refused to accept GE-contaminated corn.32
• Ethanol Corn – The most frightening example of contamination from a GE crop comes from a plant engineered to make fuel. In 2018, 38% of U.S. corn production was used to manufacture ethanol. A new GE-corn variety, Enogen, has been created with enhanced enzyme content to assist the breakdown of corn starch to sugar, the base feedstock for the fuel. In 2018, the new seeds were planted on as much as 200,000 acres, roughly 1% of all U.S. land where corn was planted for ethanol production.33
However, this new crop is a bane to corn products edible to humans. The enzymes break down the starch, leading to crumbling corn chips, soggy cereals, messy masa, and tamales that do not bind. Stunningly low contamination levels, as low as 0.01% (1 grain in 10,000), can ruin cornflakes, and 0.25% can ruin chips. At least two incidents of this contamination (one of them documented) are believed to have occurred.34
• Flax – In 2001, Canada briefly approved GE-flax for cultivation. However, this approval was ultimately rescinded because the country was concerned about loss of the European export market, which banned or discouraged GE varieties. Even though the GE seeds were supposedly destroyed, there were enough of them left to cause crop contamination. This ultimately ruined the export market when they were discovered in 2009.35 Since 60% of the country’s exports went to the EU, the loss to farmers was considerable.
• Papaya – Most papayas from Hawaii are intentionally GE. However, pollen from GE varieties has contaminated conventional and organic varieties, and even fruit in people’s gardens.36
• Rice – In 2006, it was found that GE-rice (long-grain) had contaminated the U.S. supply. It is possible that contamination had been occurring for 5 years before it was discovered. Exports were closed in Japan and many EU countries. About 11,000 affected farmers won a $750 million settlement against the seed producer, Bayer CropScience, for financial losses.37
• Wheat – Unlike other commodity crops, GE-wheat has never been approved for commercial U.S. sales. But there have been experimental varieties, with at least 2 instances where they escaped off of test plots. One of these instances, which took place in 2013, hurt the export market to other countries that prohibited GE-wheat, motivating farmers to sue to recoup damages.38
• Escaped Turf Grass – Possibly the worst example of a GE product going rogue is the release of a modified species of bentgrass. This was engineered for landscapes such as golf courses to be glyphosate tolerant. It was originally planted in an irrigated area in isolated desert terrain in Oregon to test its growth in a way that would protect the greater environment from incursion. However, wind storms dispersed its tiny seeds off the designated site, and blew its pollen as far as 13 miles away, where it bred with conventional bentgrass and possibly other grass species as well.39
The plant was so hardy that it quickly jumped to irrigation ditches, riverbanks, and the Crooked River National Grassland in Oregon, where it crowded out native grasses to the detriment of wildlife that depended on them. By 2016, it invaded noticeable parts of 3 counties in Eastern Oregon, and it had also made incursions in Idaho. In 2017, the U.S. Department of Agriculture excused the developer of the grass, Scotts Miracle-Gro, from further liability if they did not retail the product. However, the grass can never be recalled from nature, and is considered an expensive pest by area farmers – one likely to spread.
GE-bentgrass can be partially controlled by the less-toxic herbicide glufosinate, though, in twisted irony, it is likely that the grass will eventually develop resistance to this herbicide as well.
GE Water Pollution: Run-off from topically applied pesticides in water supplies is unfortunately a common consequence of industrial agriculture. Similar effects can be expected from pesticides embedded in plant tissue. Bt toxins in these GE crops have been detected 7 months after harvest, negatively affecting nearby waterways and the aquatic life in them.40
Collateral Damage to Beneficial Insects: The chemicals associated with GE crops cause real harm to pollinators.
The most well known example is the devastation of the monarch butterfly population, which has decreased 80-90% since the 1990s.41 A big reason is the near elimination of milkweed in GE crop fields by glyphosate and other herbicides used in GE crops. It is the only plant that monarch caterpillars feed on. Besides the creature’s incredible beauty, monarch butterflies assist farmers by pollinating crops.
A U.S. Geological Survey report estimated the chances of the monarch population in the Eastern U.S. going extinct by 2036 at between 11–57%.42 Another study estimated the likelihood of the monarch population in the Western U.S. going extinct at 63% by 2037.43
Honey bee populations are also harmed. Since 2006, they have experienced average winter colony declines of 29% compared to 17-20% loss typical in the 1990s.44 One possible reason is that bees are directly exposed to glyphosate herbicides, which systemically concentrate in the flowers of various crops that they pollinate.45
Bees are also exposed to neonicotinoid pesticides, another systemic toxin, that coat GE-corn seeds. Bees have extremely adverse reactions to this class of pesticide. Corn seed dust that occurs in the planting process has been observed with 700,000 times the level lethal to pollinator bees.46
Environmental Food Rating Information
Organization that offers certification for non-GMO products. A list of certified products and retailers is on Web site.
Non-GMO Shopping Guide
The Institute for Responsible Technology is an organization dedicated to education on the dangers of genetically engineered food and vitamins. Its Web site lists food brands it believes to be free of Genetically Modified Organisms (GMOs). Not all of these foods are organic, and it is possible that some brands of GMO-free food contain additives health-conscious consumers may wish to avoid.
Image: iStock.com/ giuliano2022
1 From Note 27, Organic Food.
2 Ibid., Genetically engineered varieties of corn, upland cotton, and soybeans.”
3 Ibid., Global Status of Commercialized Biotech/GM Crops in 2017.
4 2019 Agricultural Statistics Annual, Washington, DC: U.S. Department of Agriculture, National Agricultural Statistics Service, 2018, Tables 2-16 and 2-20.
5 op. cit., Global Status of Commercialized Biotech/GM Crops in 2017, p. 6.
6 Percentages of GE produce based on Ibid., pp.12-13, compared to op. cit., “2017 acreage data as of December 1, 2017.”
7 Papaya domestic production, imports, and exports from “Crops” and “Trade” databases, U.N Food and Agricultural Organization, FAOSTAT database, for year 2013.
8 Spiroux de Vendômoi, Joël, “A Comparison of the Effects of Three GM Corn Varieties on Mammalian Health,” International Journal of Biological Sciences, V. 7, No. 5, December 12, 2009, pp. 706-726.
9 Séralini, Gilles-Eric, et al., “Republished Study: long-term toxicity of a Roundup herbicide and a Roundup-tolerant genetically modified maize,” Environmental Sciences Europe, V. 26, No. 14, January 26, 2014.
10 Velimirov, A., et al., “Biological effects of transgenic maize NK603xMON810 fed in long term reproduction studies in mice,” Vienna, Austria: Institute of Nutrition, University Clinic for Farm Animals and Public. November 11, 2008.
11 Malatesta, Manuela, et al., “A long-term study on female mice fed on a genetically modified soybean: effects on liver ageing,” Histochemistry and Cell Biology, V. 130, July 22, 2008. pp. 967-977.
12 Finamore, Alberto, et al., “Intestinal and Peripheral Immune Response to MON810 Maize Ingestion in Weaning and Old Mice,” Journal of Agricultural and Food Chemistry, V. 56, November 14, 2008, pp. 11533-11539.
13 Vázquez-Padrón, RI, et al., Intragastric and intraperitoneal administration of Cry1Ac protoxin from Bacillus thuringiensis induces systemic and mucosal antibody responses in mice,” Life Sciences, V. 64, No. 21, 1999, pp. 1897-1912.
14 Ewen, Stanley, and Arpad Pusztai, “Effect of diets containing genetically modified potatoes expressing Galanthus nivalis lectin on rat small intestine,” The Lancet, V. 354, Issue 9187, October 16, 1999, pp. 1353-1354.
Fares, Nagui and Adel K. El-Sayed, “Fine Structural Changes in the Ileum of Mice Fed on delta-Endotoxin-Treated Potatoes and Transgenic Potatoes,” Natural Toxins, V. 6, 1998, pp. 219-233.
15 Genetically Engineered Food, An Overview, 2016 Edition, Washington, DC: Food & Water Watch, 2016, p. 11.
16 “2012 ARMS – Soybean Industry Highlights,” Washington, DC: U.S. Department of Agriculture, National Agriculture Statistics Service, January 2014, No. 2014-1.
17 Superweeds, Washington, DC: Food and Water Watch, July 2013, p. 8.
18 Ibid., Figure 3, p. 5.
19 Ibid., p. 5.
20 Quick Stats Database, Washington, DC: U.S. Department of Agriculture, National Agricultural Statistics Service.
21 Benbrook, Charles, “Impacts of genetically engineered crops on pesticide use in the U.S. – the first sixteen years,” Environmental Sciences Europe, V. 24, No. 24, p. 7.
22 Vyavhare, Suhas and David Kerns, “Bt Cotton,” College Station, TX: Texas A&M AgriLife Extension, ENTO-067, March 2017.
23 op. cit., Benbrook, Charles, p. 6, Table 2.
“Pesticide use increases with GM crops,” Non—GMO Report, November 1, 2012.
24 op. cit. Genetically Engineered Food, An Overview, p. 14.
26 “U.S. Contamination Episodes Concerning Genetically Engineered Crops, Fact Sheet,” Center for Food Safety, July 2015.
27 “Transgene Escape,” The IPM Practitioner, Vol. XXXV, No.3/4, February 2016, p. 2.
28 Roseboro, Ken, “Study finds large-scale escape of GM canola in US.” Non-GMO Report, September 2010.
29 op. cit. “U.S. Contamination Episodes Concerning Genetically Engineered Crops, Fact Sheet.”
33 Pate, Mikkel, “Enogen for N.D. ethanol secured for ‘18.” AgWeek, February 26, 2018.
34 Roseboro, Ken, “GMO-ethanol corn contamination raises concerns about another “StarLink” disaster,” Non-GMO Report, February 22, 2017.
35 “Flax,” Halifax, Nova Scotia, CA: Canadian Biotechnology Action Network, accessed April 11, 2020.
36 op. cit. “U.S. Contamination Episodes Concerning Genetically Engineered Crops.”
39 “USDA: Escaped, highly invasive GE grass poses no environmental harm,” Portland, OR: Center for Biological Diversity, December 7, 2016.
Rosen, Julia, “Escaped GMO bentgrass creates bitter divide in Eastern Oregon still,” High Country News, June 25, 2018.
40 Venter, Hermoine and Thomas Bohn, “Interactions Between Bt Crops and Aquatic Ecosystems,” Environmental Toxicology and Chemistry, V. 35, No. 12, August 17, 2016, pp. 2893.
41 Watling, Eve,”Monarch Butterflies Are Going Extinct. How Can We Save Them?” Newsweek, January 26, 2019.
42 Thogmartin, Wayne, et al., “Monarch butterfly population decline in North America: identifying the threatening processes,” Royal Society Open Science, V. 4, No. 9, September 20, 2017, p. 2.
43 Zuckerman, Laura, “Monarchs in western U.S. risk extinction, scientists say,” Reuters, September 7, 2017.
44 Reiley, Laura, “This past winter saw the highest honeybee colony losses on record,” Washington Post, July 5, 2019.
45 Huber, Don, “Yet Another Suspect in CCD/Dwindling?” Asheville, NC: Center for Honeybee Research, circa August 2013.
46 “Researchers: Honeybee deaths linked to seed insecticide exposure,” West Lafayette, IN: Purdue University News Service, January 11, 2012.
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