The Science Behind GMOs

What does the science say about the risks of GMOs for human health, animal health, and our environment?

Until 2012, there had been no lifetime feeding trials of GMOs to animals. And there remain a paucity of long-term studies. Most studies are done by scientists working for the biotech companies or who receive grants from them, creating significant bias.


Recent Studies and Publications

January 2014: A new study analyzed three groups of soybean samples: 1) genetically modified (GMO) soybeans, 2) non-GMO soybeans grown conventionally (with chemicals), and 3) non-GMO soybeans grown organically. Results showed that the organic soybeans had the healthiest nutritional profile and less saturated fat than the conventional and GMO soybeans. In addition to being less nutritious, the GMO soybeans also contained significant levels of glyphosate (the herbicide used on Roundup Ready crops) and Aminomethyphosphonicacid (AMPA). Click here for the full study.

June 2013: Farmers have shared numerous studies about digestive and reproductive problems in livestock that is fed genetically engineered or modified (GM) grains. A group of Midwestern farmers collaborated with scientists from around the world to conduct a scientific study to see whether these stories were well-founded. Pigs, whose digestive tract is very similar to humans, were fed a diet of GM soy and corn for five months while a control group was fed non-GM soy and corn. This is the first independent long-term feeding trial of GM to livestock that we are aware of. Click here for Dr. Judy Carman’s summary of the study.

The results are deeply concerning for anyone who suffers from or has a loved one who suffers from digestive problems, food allergies, or fertility challenges. Read the full study: A long-term toxicology study on pigs fed a combined genetically modified (GM) soy and GM maize diet.

September 19, 2012: The first peer-reviewed lifetime feeding trial of Roundup Ready corn to lab animals has been published, and the results are very disturbing! Read more about the long-term effects, including a link to the study and rebuttals to the criticisms.

June 7, 2011: Roundup and birth defects: Is the public being kept in the dark? by Michael Antoniou et al.


The New Pathogen Linked with GMOs

In January 2011, one of the nation’s senior scientists alerted the federal government to a newly discovered organism that may have the potential to cause infertility and spontaneous abortion in farm animals, raising significant concerns about human health. Dr. Don Huber, professor emeritus at Purdue University, believes the appearance and prevalence of the unnamed organism may be related to the nation’s over reliance on the weed killer known as Roundup and/or to something about the genetically engineered RoundupReady crops.

In a January 2011 letter to Secretary of Agriculture Tom Vilsack, the professor called on the federal government to immediately stop deregulation of roundup ready crops, particularly roundup ready alfalfa. You can read the letter here.

Dr. Huber wrote a second letter, in March 2011, to European officials, explaining the issue in more depth. Click here to read the second explanatory letter. 

In May 2011, FARFA worked with Food Democracy Now! on an interview with Dr. Don M. Huber to understand the science behind the pathogen found in GMO crops that has been associated with widespread plant diseases and high levels of infertility and spontaneous abortions in livestock. Watch the full interview with Dr. Huber.


Overview Articles

GM Crops – Just the Science, Non-GMO Project, 2009
A concise view of the effects of GMO crops on soil, plants, and animals from the Non-GMO Project. For further scientific studies, see articles listed below.

Don Lotter, The Genetic Engineering of Food and the Failure of Science – Part One, International Journal of Society of Agriculture & Food, 2008
Telling research by Agro-ecologist Don Lotter on the conflict evolving between science, agriculture, and big business.

Don Lotter, The Genetic Engineering of Food and the Failure of Science – Part Two, International Journal of Society of Agriculture & Food, 2008
As Don Lotter suggests in the abstract, “discussed are [the] increasing science community and university dependence on private industry funding and on development of proprietary technologies.”

Arpad Pusztai and Susan Bardocz, Potential Health Effects of Foods Derives from Genetically Modified Plants: What Are the Issues?, TWN Biotechnology & Biosafety Series 14 (2011).


Animal and Human Health Impacts

Genetically Modified Foods: Are They a Risk to Human/Animal Health?,, June 2001
A concise view of Dr. Arpad Pusztai’s view on the concerns of GMOs (article also available in Spanish).

Long term toxicity of a Roundup herbicide and a Roundup-tolerant genetically modified maize, Food and Chemical Toxicology, August 2012
Séralini, et al. studied the health effects on rats (over a period of 2 years) of a Roundup-tolerant genetically modified maize (from 11% in the diet), cultivated with or without Roundup, and Roundup alone (from 0.1 ppb in water).

Maternal and fetal exposure to pesticides association associated to genetically modified foods in Eastern Townships of Quebec, Canada, Reproductive Toxicology, doi:10.1016/j.reprotox.2011.02.004, February 2011
A Candian study by A. Aris and S. Leblanc that found that the metabolites of glyphosate and another GM-related pesticide were found in the blood of pregnant women and fetuses.

Roundup and birth defects: Is the public being kept in the dark? Earth Open Source, June 2011
Scientific research published in 2010 showed that Roundup and the chemical on which it is based, glyphosate, cause birth defects in frog and chicken embryos at dilutions much lower than those used in agricultural and garden spraying.

A Comparison of the Effects of Three GM Corn Varieties on Mammalian Health, International Journal of Biological Sciences, 2009
French researchers discuss the effects of various GMO corn on rats.

How Subchronic and Chronic Health Effects can be Neglected for GMOs, Pesticides or Chemicals, International Journal of Biological Sciences, 2009
Séralini, et al. discuss the need for further testing of GMO products based on the rise of various health related issues in humans, especially young people.

Time- and Dose-Dependent Effects of Roundup on Human Embryonic and Placental Cells, Archives of Environmental Contamination and Toxicology, November 2006
Study shows the results of testing the toxicity and endocrine disruption potential of Roundup (Bioforce) on human embryonic 293 and placental-derived JEG3 cells, but also on normal human placenta and equine testis.

BT Brinjal Event EE1: The Scope and Adequacy of the GEAC Toxicological Risk Assessment: Review of Oral Toxicity Studies in Rats, November 2010.
A review of the studies of the toxicity of GMO insecticide-producing crop, commissioned by the Indian government, by L. Gallagher.

Genetically modified crops safety assessments: present limits and possible improvements, Environmental Sciences Europe, 2011, 23:10. 
A review of GMO feeding trials, by G. Seralini et al., which concluded that the trials were not conducted for a long enough time to determine if eating GMOs could cause chronic diseases, particularly in the liver and kidneys. The review also found that the studies used “controversial protocols” and ignored statistically significant results.


Studies on Glyphosate (the active ingredient of Roundup Ready)

Compositional differences in soybeans on the market: glyphosate accumulates in Roundup Ready GM soybeans, Food Chemistry, January 2014
A study analyzing three groups of soybean samples: 1) genetically modified (GMO) soybeans, 2) non-GMO soybeans grown conventionally (with chemicals), and 3) non-GMO soybeans grown organically.

GMOs, Glyphosate, and Tomorrow, Acres USA, May 2011
An article from Dr. Don Huber, Professor Emeritus of Plant Pathology at Purdue University, detailing his concerns with GMOs.

Are We Shooting Ourselves In the Foot With a Silver Bullet?, No-Till Farmer, March 2010
Martha Ostendorf provides a condensed version of Dr. Don Huber’s findings on the adverse effects of glyphosate.

Glyphosate and glyphosate-resistant crop interactions with rhizosphere microogramisms, European Journal of Agronomy, June 2009
Robert J. Kremer (University of Missouri) and Nathan E. Means (Columbia College) discuss their findings on problems associated with glyphosate-resistant crops.

Glyphosate effects on diseases of plants, European Journal of Agronomy, April 2009
D.M. Huber and G.S. Johal, from the Department of Botany & Plant Pathology at Purdue University, discuss their research on the adverse effects of using too much glyphosate on crops.

Influence of glyphosate on Rhizoctonia and Fusarium root rot in sugar beet, Pest Management Science, 2006
This study tests the effect of glyphosate application on disease severity in glyphosate-resistant sugar beet, and examines whether the increase in disease is fungal or plant mediated.


Contamination of, and Damage to, Non-GMO Crops

Blowing in the Wind: Dealing with Roundup Herbicide Drift.  An article by FARFA Board member, farmer, and author, Eric Herm, on the realities for non-GMO farmers.

A Guide to Genetically Modified Alfalfa, Western Organization of Resource Councils (WORC), 2008
Toolkit for avoiding the environmental, agricultural, and economic risks Roundup Ready alfalfa poses to U.S. farmers, ranchers, and consumers. WORC hopes the Guide will aid discussions and activities surrounding Roundup Ready alfalfa by offering evidence and action steps to avoid the problems that would come with widespread adoption.

Frequency of Pollen Drift in Genetically Engineered Corn, ISB News Report, February 2005
B.L. Ma discusses the concern of GM corn drift contaminating non-GMO corn.