600+ published safety assessments

It is frequently claimed that GM foods are not properly tested, or asserted that few independent studies have been published to establish their safety. Another similar claim made is that the food regulatory agencies rely exclusively of corporate information to decide whether GM food and feed are safe. The further claim is made that very few independent tests relating to GM food safety are done.

This conventional 'wisdom' is wrong.

The modern scientific literature shows that these commonly held opinions are merely myths.  Academics Review website comprehensively shows that many of these myths are merely baseless rumours and misinformation.

Currently there are near 2000 peer-reviewed reports in the scientific literature which document the general safety and nutritional wholesomeness of GM foods and feeds.

Citations to 400+ of these published studies are provided at the searchable GENERA Database accessible here. A longer 600+ list is here.
 (see also explanatory comment Making sense of lists of studies by Karl Haro von Mogel on 25 October 2013)


GENERA’s mission is to be a searchable database of peer-reviewed research on the relative risks of genetically engineered crops that includes important details at-a-glance. This database is intended to be comprehensive, to include all of the relevant research, and to accurately report the outcomes of each study as reported by the authors. To increase transparency, the funding sources of each study are listed, which requires contacting the authors of any paper that does not report this information. By including and reporting important details about all of the relevant peer-reviewed scientific studies – not just those that fit a pre-determined conclusion – GENERA will allow members of the public to easily compare large amounts of research to form their own conclusions about the relative risks of genetic engineering.
Biology Fortified, Inc.

GENERA is a project of Biology Fortified, Inc. (BFI), an independent non-profit organization incorporated in Middleton, Wisconsin, USA. The Atlas concept, layout, and programming was conceived, designed, and implemented by BFI, which maintains the Atlas as a free public resource. BFI is independently funded.

GENERA release announcement here. 50 percent of studies are independent.

The team at BFI is already seeing patterns in the research. Out of the first 400 randomly-selected studies available in the GENERA beta test, half of them are funded entirely by government agencies and independent nonprofit organizations. Before the project began, rough estimates placed them at just a third of the research. And the government-funded research is worldwide in scope – concentrated in Europe and Asia, followed by North America and Australia. These findings should turn the heads of people who thought it was skewed to private, U.S.-based laboratories.

Curious about the industry funded GMO studies?…see Marc Brazeau at Biology Fortified

  • A recent review on the general GM safety topic, in agreement with the above statement and mentioning 1783 papers, is this:
An overview of the last 10 years of genetically engineered crop safety research.
[This data set is available from the first author .]
Nicolia A, Manzo A, Veronesi F, Rosellini D. Crit Rev Biotechnol. 2013 Sep 16. [Epub ahead of print]
The technology to produce genetically engineered (GE) plants is celebrating its 30th anniversary and one of the major achievements has been the development of GE crops. The safety of GE crops is crucial for their adoption and has been the object of intense research work often ignored in the public debate.
We have reviewed the scientific literature on GE crop safety during the last 10 years, built a classified and manageable list of scientific papers, and analyzed the distribution and composition of the published literature. We selected original research papers, reviews, relevant opinions and reports addressing all the major issues that emerged in the debate on GE crops, trying to catch the scientific consensus that has matured since GE plants became widely cultivated worldwide. The scientific research conducted so far has not detected any significant hazards directly connected with the use of GE crops; however, the debate is still intense. An improvement in the efficacy of scientific communication could have a significant impact on the future of agricultural GE.
Our collection of scientific records is available to researchers, communicators and teachers at all levels to help create an informed, balanced public perception on the important issue of GE use in agriculture.

From Nicolia 2013
Table 1. Classification of 1783 scientific records on GE crop safety published between 2002 and 2012. 
Topic                                                                          No. of papers 
General literature (GE gen)                                                   166  
Interaction of GE crops with the environment (GE env)      847  
Biodiversity                                                                             579  
Gene flow                                                                                268  
Gf – Wild relatives                                                                 113  
Gf – Coexistence                                                                    96  
Gf – Horizontal gene transfer in soil                                      59  
Interaction of GE crops with humans and animals
(GE food and feed)                                                               770  
Substantial equivalence                                                         46  
Non-targeted approaches to equivalence assessment   107  
GE food/feed consumption                                                 312  

Traceability                                                                            305 

Note also that by December 2010, 15 years, 81 projects, 400 teams and at least €130 million had been spent by European Union taxpayers on issues relating to GMO safety or GMO acceptance. (This is  documented in December 2010 at another GMO Pundit posting, and is described at a comprehensive European commission website.).

A summary report on this major project is available as a pdf file:EUROPEAN COMMISSION 2010 A Decade of EU-funded GMO research 

Animal feeding characteristics is another indicator of food wholesomeness. The following website provides access to many studies:


The GM Feed Consumption Database contains data from the comparision of health and productivity on livestock animals fed with GM and non-GM feed for specified period of time. Data have been collected through controlled feeding studies carried out by various organizations and research teams.Each database record represents single measurement of different parameters of livestock animals in relation of their growth, health or productivity. The record contains 25 attributes describing the animal, the characteristics of the GMO in the feed, the type of feed, the duration of the trail, the measured parameter and the observed statistical differences as stated by the authors and the reference and link to the original publication.

Listing papers is clearly only a start to discussions of crop safety. Carefully considered peer-reviewed safety assessments based on such published papers are needed to reach conclusions about safety of transgenic crops. Three such reviews that do this are the following. (Several others are given in links that follow, down the page.)

A good place to start reading is at the first article, by Alan McHughen, recently posted at the GLP website

GMO Safety and Regulations
Alan McHughen | December 16, 2014 | University of California
Calls for increased regulation do not account for the robust review already in place. The safety of GM food and crops is not in question in the scientific community. The current regulatory program ensures their safety both in the farm field and for consumers.

  • Every major scientific body in the U.S. and around the world has reviewed independent research related to GM crops and food and has concluded they are as safe as food and crops developed from other methods in use today.
  • New non-genetically engineered (GE) foods and crops are continually being added to the marketplace. None of these non-GE crops undergo safety testing and review prior to commercialization even though the potential exists for changes that could be harmful, while GE crops and foods must meet rigorous standards of safety.
  • GM crops and foods are regulated at every stage of production from research planning through field-testing, food and environmental safety assessment, and after commercial use.
  • GM crops and foods have been in use in the U.S. for 30 years with no evidence, despite allegations, that they cause any harm.
  • GM foods contain the same nutritional attributes as like foods produced with non-GM crops (although some may contain added nutritional benefits, such as vitamin enhancements). Any GM food with significantly lower nutritional attributes would be rejected in the regulatory process
  • In decades of testing in the lab and in field trials, a transferred gene has never been known to produce a new allergen, toxin or anything functionally different from what was expected.
(Read much more at the above link.)

  • A comprehensive broad examination became available May 17, 2016 from the US National Academy of Sciences:
Distinction Between Genetic Engineering and Conventional Plant Breeding Becoming Less Clear, Says New Report on GE Crops

WASHINGTON – An extensive study by the National Academies of Sciences, Engineering, and Medicine has found that new technologies in genetic engineering and conventional breeding are blurring the once clear distinctions between these two crop-improvement approaches. In addition, while recognizing the inherent difficulty of detecting subtle or long-term effects on health or the environment, the study committee found no substantiated evidence of a difference in risks to human health between current commercially available genetically engineered (GE) crops and conventionally bred crops, nor did it find conclusive cause-and-effect evidence of environmental problems from the GE crops. However, evolved resistance to current GE characteristics in crops is a major agricultural problem.
A tiered process for regulating new crop varieties should focus on a plant’s characteristics rather than the process by which it was developed, the committee recommends in its report. New plant varieties that have intended or unintended novel characteristics that may present potential hazards should undergo safety testing -- regardless of whether they were developed using genetic engineering or conventional breeding techniques. New “-omics” technologies, which dramatically increase the ability to detect even small changes in plant characteristics, will be critical to detecting unintended changes in new crop varieties...

  • The comprehensive GRACE EU Wistar rat feeding study is also available:

(full Archives of Toxicology GRACE article here pdf file)

Assessment of GE food safety using '-omics' techniques and long-term animal feeding studies.
Ricroch AE. N Biotechnol. 2013 May 25;30(4):349-54. doi: 10.1016/j.nbt.2012.12.001. Epub 2012 Dec 17.
AgroParisTech, Chair of Evolutionary Genetics and Plant Breeding, 16, rue
Claude-Bernard, 75005 Paris, France.

Despite the fact that a thorough, lengthy and costly evaluation of genetically engineered (GE) crop plants (including compositional analysis and toxicological tests) is imposed before marketing some European citizens remain sceptical of the safety of GE food and feed. In this context, are additional tests necessary? If so, what can we learn from them? To address these questions, we examined data from 60 recent high-throughput '-omics' comparisons between GE and non-GE crop lines and 17 recent long-term animal feeding studies (longer than the classical 90-day subchronic toxicological tests), as well as 16 multigenerational studies on animals. The '-omics' comparisons revealed that the genetic modification has less impact on plant gene expression and composition than that of conventional plant breeding. Moreover, environmental factors (such as field location, sampling time, or agricultural practices) have a greater impact than transgenesis. None of these '-omics' profiling studies has raised new safety concerns about GE varieties; neither did the long-term and multigenerational studies on animals.
Therefore, there is no need to perform such long-term studies in a case-by-case approach, unless reasonable doubt still exists after conducting a 90-day feeding test. In addition, plant compositional analysis and '-omics' profiling do not indicate that toxicological tests should be mandatory. We discuss what complementary fundamental studies should be performed and how to choose the most efficient experimental design to assess risks associated with new GE traits. The possible need to update the current regulatory framework is discussed.

Assessment of the health impact of GM plant diets in long-term and multigenerational animal feeding trials: a literature review.
Snell C, Bernheim A, Bergé JB, Kuntz M, Pascal G, Paris A, Ricroch AE.2 Food Chem Toxicol. 2012 Mar;50(3-4):1134-48. doi: 10.1016/j.fct.2011.11.048. Epub 2011 Dec 3.

The aim of this systematic review was to collect data concerning the effects of diets containing GM maize, potato, soybean, rice, or triticale on animal health. We examined 12 long-term studies (of more than 90 days, up to 2 years in duration) and 12 multigenerational studies (from 2 to 5 generations). We referenced the 90-day studies on GM feed for which long-term or multigenerational study data were available. Many parameters have been examined using biochemical analyses, histological examination of specific organs, hematology and the detection of transgenic DNA. The statistical findings and methods have been considered from each study. Results from all the 24 studies do not suggest any health hazards and, in general, there were no statistically significant differences within parameters observed. However, some small differences were observed, though these fell within the normal variation range of the considered parameter and thus had no biological or toxicological significance. If required,  a 90-day feeding study performed in rodents, according to the OECD Test Guideline, is generally considered sufficient in order to evaluate the health effects of GM feed. The studies reviewed present evidence to show that GM plants are nutritionally equivalent to their non-GM counterparts and can be safely used in food and feed.
A database in spreadsheet format is available from the corresponding author on request.

"These field data sets representing billions of observations did not reveal unfavorable or unexpected trends in livestock health and productivity. The available health indicators from US livestock suggest that these rates actually improved over time despite widespread adoption of GE crops in US agriculture and increasing levels of GE content in livestock diets. There was no indication of worsening animal health after the introduction of GE feed, and productivity improvements continued in the same direction and at similar rates as those that were observed before the introduction of GE crop varieties in 1996."

These above mentioned reviews focus of scientific evidence, but the perceptions of safety rests on broader aspects of human behaviour and culture. Economist AJ Stein does a very good job briefly touring those issues here:

Conflict of interest involvling affiliations of author's with biotechnology companies is sometimes a reason to doubt safety assessments. THis has been evaluated:
  • Conflict of interests and evidence base for GM crops food/feed safety research

...In terms of COIs, we found that a majority—406 out of 698 reports (58.3%)—have no financial or professional COIs, as the authors were not affiliated with companies that develop GM crops and also declared that the funding sources did not come from those companies. Overall, 180 out of 698 articles (25.8%) had COIs either in terms of the author affiliation or declared funding source. The distribution of COIs across categories is uneven. Over 70% of reports related to three out of the eight categories (allergenicity potential, processing and unintended effect; Table 1) show no COIs (financial or professional). Overall, research carried out by scientists unrelated to companies that develop GM crops, but for which the authors did not provide funding information, represented 15.9% of the total reports (111 articles; Table 1)....
Miguel A Sanchez Nature Biotechnology 33, 135–137 (2015) doi:10.1038/nbt.3133


Need even more nitty-gritty details?

  • Here is a summary of individual safety assessments in a pdf file at the Website GMO Answers:

Safety assessment of genetically modified plants with deliberately altered composition
Nigel G. Halford, Elizabeth Hudson, Amy Gimson, Richard Weightman, Peter R. Shewry and Steven Tompkins 2014.
 Plant Biotechnology Journal  Article first published online: 16 APR 2014 DOI: 10.1111/pbi.12194

The development and marketing of ‘novel’ genetically modified (GM) crops in which composition has been deliberately altered poses a challenge to the European Union (EU)'s risk assessment processes, which are based on the concept of substantial equivalence with a non-GM comparator. This article gives some examples of these novel GM crops and summarizes the conclusions of a report that was commissioned by the European Food Safety Authority on how the EU's risk assessment processes could be adapted to enable their safety to be assessed.

The conclusions about extensive testing is further confirmed by the UK Biochemical Society Statement 2011:

"Genetically modified" crops, feed and food
All our current crop plants, and domestic and farm animals, are the result of deliberate cross breeding, which leads to genetic reshuffling, followed by selection of desirable characteristics. Although breeders have successfully practised these activities for thousands of years, it was only during the past century that we have gained a detailed understanding of the genetic and biochemical changes, which make these new breeds both genotypically and phenotypically very different from their ancestral forms.
Plant breeding, together with agrochemicals, irrigation and mechanisation, has led to dramatic increase in crop yields, which have kept pace with the burgeoning increase in global population in recent years. However, we now realise that this 'Green Revolution' put unprecedented pressure on the environment and on biodiversity. To ensure food security and adequate nutrition for a population of 9 billion by 2050 - with most of them living in the developing world-in a sustainable and environmentally friendly manner, we will need to double productivity on essentially the same area of land. At the same time, we need to address concerns about modern high input agriculture, regionally declining water availability and to adapt to man-made climate change .
During the past few decades, the world has seen a revolution in our understanding of how living organisms function at the molecular, biochemical and physiological levels, culminating in the complete genome sequences of an ever increasing range of organisms, from viruses to man. This information is a vital resource for addressing many challenges: combating disease, improving human health and well-being, and enhancing food supply.
As part of this revolution, we have seen the development of plant genetic modification (GM), which allows the transfer of desirable genetic properties from one plant species - or from other organisms - into another plant species. All GM crops are subject to extensive selection testing and characterisation mandated by an elaborate regulatory regime in order to exclude any potential adverse health and "environmental" consequences before they are licensed to be grown commercially.
The majority of GM crops currently grown have been modified to provide resistance to insect pests or tolerance to benign herbicides. This enables a more targeted and efficient use of agrochemicals together with the associated benefit of 'conservation tillage'. Other GM traits that are currently being developed for regulatory approval include further improvements in resistance to pest and disease; improving the efficiency of nutrient use; tolerance to temperature extremes, drought and flooding; and biofortified crops with enhanced micronutrients to combat nutritional deficiencies, which have a dramatic effect on the health of women and children in the developing world, and are a major cause of death and disease.
The Biochemical Society recognises that GM crops are not a magic bullet that will feed the whole world or eliminate poverty. However, the application of molecular biology will allow more targeted, precise, predictable and controllable improvement of crops, and can be used in two major ways: marker-assisted breeding to develop new varieties faster and GM to introduce new traits into crop plants. These technologies must not only be applied to improve food production in major crops but also to orphan crops those of minor economic significance, and so perhaps overlooked in commercial developments, but nevertheless of great importance for specific populations, often very poor ones in the developing world eg.Cassava,Sorghum), which are a vital resource for farmers in the developing world. As a scientific society, we have a responsibility for fully evaluating and deploying these technologies where appropriate, and thus contributing to the security of future generations; unfortunately, time is not on our side.
The Biochemical Society supports the view that, while it is indeed proper to maintain a reasonable level of regulatory control, a wealth of experience and experimental data from national academies, governments and regulatory authorities has shown that the use of GM techniques presents no particular or novel hazards beyond those already encountered in agriculture. This view has just been clearly endorsed in an EU report : "According to the projects' results, there is, as of today, no scientific evidence associating GMOs with higher risks for the environment or for food and feed safety than conventional plants and organisms".

The Biochemical Society wishes to thank Chris Leaver CBE FRS FRSE Emeritus Professor of Plant Science and Emeritus Fellow of St Johns College, Oxford for his work in producing this position statement.
  United Nations (Economic and Social Affairs) 2004 'World Population to 2300'
  Royal Society October 2009 'Reaping the Benefits: Science and the sustainable intensification of global agriculture'
  Europa December 2010 'Commission publishes compendium of results of EU-funded research on genetically modified crops'

  • The US FDA reports a lot of consultation and analysis of GM crop safety here:

Completed Consultations on Bioengineered Foods 
The inventory at this link. lists all completed consultations on bioengineered foods evaluated under FDA’s 1992 Statement of Policy: Foods Derived from New Plant Varieties. More information about this inventory is available on the Introduction page to the FDA List of Completed Consultations on Bioengineered Foods. We will update this information within about one month of completing a consultation. 

As part of this current GMO Pundit collection there are numerous independent published studies of GM food safety (Exhibit 2). Food and genetic technology regulatory agencies such as OGTR and FSANZ  in Australia and EFSA in Europe access all this publicly available safety literature as part of their assessment process for the safety of GM foods and feeds.

In contrast there is no strongly documented scientific validation of the safety of many conventional foods in the scientific literature -- especially relatively novel conventional foods such as kiwi fruit. There are numerous safety issues raised by conventional foods, and food safety has to be judged by comparison against this starting point, not an unattainable concept of absolute safety, whose pursuit actually can increase real harms to people. This viewpoint of the unavoidable risks from conventional food is well documented, appearing in an authoritative textbook of toxicology (C. D. Klaassen 2008, Editor. Casarett and Doull's Toxicology 7th Edition, Chapter 30, Food Toxicology).

As Drs Chassy and Tribe argue at Academics Review, for effective  Food Safety: Focus on Real Risks, Not Fake Ones
Disease microbes, nutrient shortages and lack of access are greatest threats, not biotechnology. Contamination of fish and meat with parasites, or grains with mold toxins, are also significant food health hazards (Chassy and Tribe 2010).
To quote further from a recent review: Knudsen, I., Søborg, I., Eriksen, F., Pilegaard, K., Pedersen, J., Risk Management and Risk Assessment of Novel Plant Foods: Concepts and Principles, Food and Chemical Toxicology (2008), doi: 10.1016/j.fct.2008.01.022
Direct quote:
"During the last two decades a lot of attention has been paid to the safety assessment of genetically modified organisms used as food. Several international reports have indicated that the safety assessment strategy recommended for genetically modified foods to a large extent also could be used for other kinds of novel foods. Another conclusion from many of these reports is that very little is known about the potential long-term health effects of any traditional food (e.g. FAO/WHO 2000). Nonetheless, most traditional foods are treated as being safe because no widespread occurrence of acute severe adverse effects is reported after their consumption. Their safety has, however, rarely, if ever, been established. While it has been commonly accepted that for example food additives should be thoroughly tested for safety prior to use in the food production in order to secure that their level in the final food product would not constitute a human health risk, foods from new plant lines or new exotic fruits and vegetables have not been evaluated to the same extent for their potential adverse effects on human health although there are several examples of risks connected to such foods."
In other words, GM foods are more rigorously assessed for safety than many conventional foods, or other new types of foods such as kiwi fruit, and exotic foods that are new to certain communities (such as quinoa from South America or nangai nuts (Canarium indicum) from Micronesia). GM crops are more highly regulated than new breeds of cereals, potatoes, or tomatoes that contain fresh germplasm from wild-plants that is often introduced into our food by conventionial breeders to provide pest resistance.

To further redress the misinformation about safety testing of GM foods and feeds, four major Exhibits relating to GM food and feed safety are collected below:
  1. Key review articles on testing of GM food and feed safety, and on animal feeding trials with GM food and feed. 
  2. Link to a summary of affiliations of scientists publishing on food safety, to enable their degree of independence to be scrutinised, plus links to original papers where available.
  3. A collected list of 600+ published primary research articles including GM animal feeding tests, and papers relating directly to experimental testing of GM food safety and wholesomeness.
  4. Base-line studies on variability, risks and unpredictable outcomes from conventional breeding (relocated to a separate Baseline crop safety page) 
Exhibit 3 is a large document, but the point of presenting so many papers is to refute assertions that such studies are seldom published.

Important papers are bolded in the lists below.

As far as discussing GM food safety myths, Academics Review is highly recommended. Genetic Roulette, a book by Jeffrey Smith, has 65 myths in full display. The results of investigating the claims in Genetic Roulette were published in March 2010 here

Some people worry about DNA in our food. Here is a simple discussion of it.

One particularly important soon to be available GM crop is vitamin A fortified rice or Golden Rice. Safety issues about this crop are discussed here:

Frequently asked questions on Golden Rice
Here are answers to common questions about Golden Rice and links to relevant scientific resources from organizations working on vitamin A deficiency, plant breeding, and genetic modification.

A related topic the GMO safety is the safety analysis of double-stranded silencing RNAs. That is covered in GMO Pundit's RNAi Reader page.

Exhibit 1.
KEY GMO Pundit Posts:
Safety, safety, safety, and more GM food safety. 
(Collected professional reviews on GM food and feed safety, including an impressive septet from Food and Chemical Toxicology Journal.) 
Gene-chips prove transgenes are clean genes.
(Collected papers on transcriptomics, metabolomics, proteomics and other comprehensive profiling approaches showing transgenic insertions are clean)

RNA related safety issues (collected papers and posts, also accessible via black bar at top of blog).
Timely WHO report on glyphosate herbicide's potential for causing cancer by the dietary intake route (May 2016; Relevent to GMOs as herbicide tolerance is a widely used trait, raising the issue of glyphosate residue safety

Key Quote WHO 2016:
The Meeting concluded that glyphosate is unlikely to be genotoxic at anticipated dietary exposures. Several carcinogenicity studies in mice and rats are available. The Meeting concluded that glyphosate is not carcinogenic in rats but could not exclude the possibility that it is carcinogenic in mice at very high doses. In view of the absence of carcinogenic potential in rodents at human-relevant doses and the absence of genotoxicity by the oral route in mammals, and considering the epidemiological evidence from occupational exposures, the Meeting concluded that glyphosate is unlikely to pose a carcinogenic risk to humans from exposure through the diet
Molecular profiling review.

Food Safety Authority (UK)

G02006: Metabolome technology for the profiling of GM and conventionally bred plant materials

Major new joint EU scientific report on GM food safety 
10th Sept 2008. The European Commission's Joint Research Centre released a new study entitled "Scientific and technical contribution to the development of an overall health strategy in the area of GMOs".

Its key messages are (direct quotes from Executive Summary):

  1. No demonstration of any health effect of GM food products submitted to the regulatory process has been reported so far, yet, little is known about the potential long term health effects of any food, including novel food.
  2. The safety of a GMO derived product is established relative to its conventional counterpart and is, therefore, not absolute. Conventional food is often evaluated on the base of its history of safe use.
  3. The assessment of potential toxicity commonly includes the search for similarities between the primary structure of the protein(s) introduced by genetic modification into the host organism and the structures of known toxic proteins using bio-informatics methods. In addition, the susceptibility of the newly introduced protein to conditions of food and feed processing, as well as digestion, can provide an indication of the likelihood that the consumer will be exposed to the intact protein.
  4. Repeated-dose feeding of new proteins in a subchronic experiment (e.g. for 28 days), are recommended. However, in a number of dossiers that have already been notified for regulatory approval in the EU subchronic 90-day wholeproduct feeding studies in rodents (rats) have been provided. Such studies should not be done on a routine basis, but only if there are indications to do so, such as substantial differences observed in the compositional analysis between the GM and its non-GM comparator.
  5. With respect to allergenicity a weight of evidence approach is recommended combining the outcome of various assessment methods. Various studies published in scientific literature focus on the possible allergenic effects of the market-approved GM crops. Sera binding or skin reactions have not been observed for GM crops that have been allowed onto the European market.
  6. Genes of bacterial origin in GM plants may theoretically be capable of being taken up by bacteria in the food chain. Horizontal gene transfer risks have been raised with respect to antibiotic resistance genes which may devolve to pathogenic micro-organisms thereby impairing antibiotic therapy. However, the chances of acquiring the same gene(s) from other bacterial species in the environment rather than from GMOs are considered much greater.
  7. Two points are of paramount importance to consider possible consequences for human and animal safety in the rare cases of uptake of DNA from food by mammalian cells. First, DNA sequences of various origins (plant, animal, microbia, virus) are always present in human food and farm animal feed. Therefore, most sequences to be found in GM crop plants will have entered the mammalian gut before present time. Second, it is clear that uptake is very much more probable for somatic cells (particularly those of the gut and immune systems) than for germ line cells. This may account for the almost complete lack of evidence for sequences of plant origin in mammalian genomes. Somatic cells of the gut lining have a rapid turnover, such that the most likely fate of most modified cells is to be lost in the faeces. These considerations make deleterious consequences improbable.
    Unintended effects are those not directly linked to the targeted genetic modifications (disruption in the natural function of genes); this may also occur in conventional crop breeding.
  8. Changes in the nutrient composition of GMO product may impact on human and animal nutrition; in such case in vivo feeding trials may be decided depending upon the knowledge available on those nutrients.
  9. GM crops which are metabolically engineered to produce nutrients (or other products) of interest are likely to be prone to unintended effects besides the modification of interest. In such case, advanced omics technologies can be used to identify the substance(s) linked to the transfonnation. Comparison with a conventional counterpart is used, taking into account natural background variations. Generally, it is considered that the routine application of these techniques in regulatory risk assessment requires additional harmonisation and validation, as well as development of databases for the data on background variation.
  10. Precaution is the reason for the comprehensive pre-market safety assessment and follow-up by post-market monitoring currently applied to GMOs, in order to reduce the uncertainty regarding any potential health effects of GM technology to a minimum.
  11. Current experience with long term testing of GMO carried out in the fonnal regulatory approval context, point with an appropriate : degree of certainty to the absence of potential health effects. The data evaluated for submitted GM dossiers do not indicate any harm caused by these GMOs.
  12. Most of the multigenerational feeding studies perfonned with laboratory rodents show no significant effect on testicular spennatocytes (GM soya beans), on fertility (GM potatoes), cell ultrastructure (GM soya beans) and only diet-related changes with GM canola. No uptake of transgenic DNA from gastrointestinal tract has been observed. Human experiments with GM tilapia fish showed no differences in cytological and biochemical blood composition.
GMO Pundit agrees with these judgements, and this post and others at this site provide abundant documentation of their validity.

CropLife Database of the Safety and Benefits of Biotechnology

OTHER KEY REVIEW resources on GM food nutritional safety evaluation. 


The GM Science Review Panel has concluded its work and published a first and a supplementary second report. These have been formally submitted to: Margaret Beckett, Secretary of State for the Environment, Food and Rural Affairs, Allan Wilson MSP at the Scottish Executive, Carwyn Jones AM at the National Assembly for Wales, and Mrs Angela Smith Parliamentary Under Secretary of State at the Northern Ireland Office, to help inform government's decision making on GM crops and food. 

An open review of the science relevant to GM crops and food based on the interests and concerns of the public


Herman, Rod A. William D. Price 2013 Unintended Compositional Changes in Genetically Modified (GM) Crops: 20 Years of Research. J. Agric. Food Chem., DOI: 10.1021/jf400135r

Mycotoxin content and safety of GM foods.

The benefit of Bt [GM] corn’s reduction of mycotoxin damage has been virtually ignored in policy debates anywhere in the world. As adoption of agricultural biotechnology continues to increase on a global scale, policy makers worldwide should consider the economic and health impacts of this secondary benefit of transgenic pest-protected crops. A superb recent paper by F Wu remedies deficiency in policy debate, and the following draws very heavily on F Wu's important scholarship. Reduction of mycoxin contamination is a clear parameter for food and feed safety, particularly in developing countries. Further details and extensive discussion in a GMO Pundit Post here.
  • Mycotoxin reduction in Bt corn: potential economic, health, and regulatory impacts
Genetically modified (GM) Bt corn, through the pest protection that it confers, has lower levels of mycotoxins: toxic and carcinogenic chemicals produced as secondary metabolites of fungi that colonize crops. In some cases, the reduction of mycotoxins afforded by Bt corn is significant enough to have an economic impact, both in terms of domestic markets and international trade. In less developed countries where certain mycotoxins are significant contaminants of food, Bt corn adoption, by virtue of its mycotoxin reduction, may even improve human and animal health. This paper describes an integrated assessment model that analyzes the economic and health impacts of two mycotoxins in corn: fumonisin and aflatoxin. It was found that excessively strict standards of these two mycotoxins could result in global trade losses in the hundreds of millions $US annually, with the US, China, and Argentina suffering the greatest losses. The paper then discusses the evidence for Bt corn’s lower levels of contamination of fumonisin and aflatoxin, and estimates economic impacts in the United States. A total benefit of Bt corn’s reduction of fumonisin and aflatoxin in the US was estimated at $23 million annually. Finally, the paper examines the potential policy impacts of Bt corn’s mycotoxin reduction, on nations that are making a decision on whether to allow commercialization of this genetically modified crop.
Keywords Bt corn - economic impacts - health impacts - mycotoxin reduction - regulatory policy

Felicia Wu
Environmental, Occupational Health, Graduate School of Public Health, University of Pittsburgh, 130 DeSoto St.,
Pittsburgh, PA, 15261, USA
Transgenic Research (2006) 15:277–289 Springer 2006
DOI 10.1007/s11248-005-5237-1
Two earlier reviews by Wu reviews of fumonisin reduction in Bt-corn, see Felicia Wu et al., The Economic Impact of Bt Corn Resulting from Mycotoxin Reduction, 23 J. TOXICOLOGY, TOXIN REVS. 397 (2004) , and Felicia Wu, Mycotoxin Risk Assessment for the Purpose of Setting International Regulatory Standards, 38 ENVTL. SCI. & TECH. 4049 (2004). 

  • Compositional differences between near-isogenic GM and conventional maize hybrids are associated with backcrossing practices in conventional breeding.

Here, we show that differences between genetically modified (GM) and non-GM comparators cannot be attributed unequivocally to the GM trait, but arise because of minor genomic differences in near-isogenic lines. Specifically, this study contrasted the effect of three GM traits (drought tolerance, MON 87460; herbicide resistance, NK603; insect protection, MON 89034) on maize grain composition relative to the effects of residual genetic variation from backcrossing.
Important features of the study included (i) marker-assisted backcrossing to generate genetically similar inbred variants for each GM line, (ii) high-resolution genotyping to evaluate the genetic similarity of GM lines to the  corresponding recurrent parents and (iii) introgression of the different GM traits separately into a wide range of genetically distinct conventional inbred lines. The F1 hybrids of all lines were grown concurrently at three replicated field sites in the United States during the 2012 growing season, and harvested grain was subjected to compositional analysis. Proximates (protein, starch and oil), amino acids, fatty acids, tocopherols and minerals were measured. The number of statistically significant differences (α = 0.05), as well as magnitudes of difference, in mean levels of these components between corresponding GM variants was essentially identical to that between GM and non-GM controls. The largest sources of compositional variation were the genetic background of the different conventional inbred lines (males and females) used to generate the maize hybrids and location. The lack of any compositional effect attributable to  GM suggests the development of modern agricultural biotechnology has been accompanied by a lack of any safety or nutritional concerns.
Venkatesh TV(1), Cook K, Liu B, Perez T, Willse A, Tichich R, Feng P, Harrigan GG. Plant Biotechnol J. 2015 Feb;13(2):200-10. doi: 10.1111/pbi.12248. Epub 2014 Sep 4.

Drew L. Kershen
FOOD DRUG LAW JOURNAL, v. 61 # 2 (June 2006) pages 197-236) published 27th June.
(A hyperlink to a full pdf copy of the review will follow within a few days courtesy of Professor Kershen)

Genetically modified plants as fish feed ingredients

(Discusssed here

Genetically modified (GM) plants were first grown commercially more than 20 years ago, but their use is still controversial in some parts of the world. Many GM plant varieties are produced in large quantities globally and are approved for use in fish feeds both in Norway and the European Union. European consumers, however, are skeptical to fish produced by means of GM feed ingredients. Concerns have been raised regarding the safety of GM plants, including potential toxicity and (or) allergenicity of the novel protein, potential unintended effects, and risk of horizontal gene transfer to other species. This review will present the current state of knowledge regarding GM plants as fish feed ingredients, focusing on fish performance and health as well as the fate of the GM DNA fragments in the fish, identifying limitations of the current work and areas where further research is needed.

Nini Hedberg Sissener, Monica Sanden, Åshild Krogdahl, Anne-Marie Bakke, Lene Elisabeth Johannessen, Gro-Ingunn Hemre

a National Institute of Seafood and Nutrition Research (NIFES), P.O. Box 2029 Nordnes, 5817 Bergen, Norway.
b Norwegian School of Veterinary Science, Department of Basic Sciences and Aquatic Medicine, Aquaculture Protein Centre, N-0033 Oslo, Norway.
c National Veterinary Institute, P.O. Box 750 Sentrum, N-0106 Oslo, Norway.
Published on the web 23 February 2011.
Canadian Journal of Fisheries and Aquatic Sciences, 2011, 68:(3) 563-574, 10.1139/F10-154

  • Glyphosate herbicide carcinogenicity:

Greim, H., D. Saltmiras, V. Mostert, and C. Strupp (2015). Evaluation of carcinogenic potential of the herbicide glyphosate, drawing on tumor incidence data from fourteen chronic/carcinogenicity rodent studies. Rev. Toxicol. A new scientific publication examining 14 separate cancer studies in rats and mice conducted over the last several decades concludes that there is no evidence that glyphosate, the active ingredient in Roundup branded herbicides, causes cancer. The article, in Critical Reviews in Toxicology, evaluated the data from these long-term studies to determine whether there were any patterns to suggest humans exposed to glyphosate would have any concern about developing cancer. Other scientifically relevant information such as expert regulator evaluations, human dietary exposures and epidemiological studies were also discussed. The clear and consistent view across more than 30 years of relevant information continues to support the first expert opinions from the 1980s, that glyphosate does not cause cancer.

Sorahan, T. (2015). Multiple Myeloma and Glyphosate Use: A Re-Analysis of US Agricultural Health Study (AHS) Data. J. Environ. Res. Public Health Summary: A new look at data from the US Agricultural Health Study (AHS) clarifies that there is no relationship between glyphosate use and the risk of multiple myeloma, a type of cancer. The article considered data collected from over 57,000 pesticide applicators to determine whether a relationship exists between multiple myeloma and glyphosate exposure. These results contradict the outcome of a previous analysis of AHS data that relied on a restricted data set to reach a different conclusion. This reanalysis of the full AHS data set for multiple myeloma is consistent with other epidemiological and laboratory research that demonstrated glyphosate does not cause cancer.

 Kier, L. D. (2015). Review of Genotoxicity Biomonitoring Studies of Glyphosate-Based Formulations. Rev. Toxicol. 
Summary: Human and environmental genotoxicity biomonitoring studies involving exposure to glyphosate-based formulations (GBFs) were reviewed to complement an earlier review of experimental genotoxicity studies of glyphosate and GBFs (Kier and Kirkland, 2013). The results of the biomonitoring studies do not contradict an earlier conclusion derived from experimental genotoxicity studies that typical GBFs do not appear to present significant genotoxic risk under normal conditions of human or environmental exposures.

 Kier, LD and DJ. Kirkland (2013). Review of genotoxicity studies of glyphosate and glyphosate-based formulations. Rev. Toxicol. 43:283. Summary: An earlier review of the toxicity of glyphosate and the original Roundup -branded formulation (Williams et al., 2000) concluded that neither glyphosate nor the formulation poses a risk for the production of heritable/somatic mutations in humans. The present review of subsequent genotoxicity publications and regulatory studies of glyphosate and glyphosate-based formulations (GBFs) incorporates all of the findings into a weight of evidence for genotoxicity. Glyphosate and typical GBFs do not appear to present significant genotoxic risk under normal conditions of human or environmental exposures.

 Mink, P., J. Mandel, B. Sceurman, J. Lundin (2012). Epidemiologic studies of glyphosate and cancer: A review. Toxicol. Pharm. 63:3. A review of 21 epidemiological studies found no causal relationship between exposure to glyphosate and cancer in adults or children. This observation is consistent with conclusions from regulatory authorities that glyphosate is unlikely to pose a risk to human health based on previous toxicology studies.

 Niemann, L., C. Sieke, R. Pfeil, R. Solecki (2015). A critical review of glyphosate findings in human urine samples and comparison with the exposure of operators and consumers. Consum. Protect. Food Safety. Summary: The German Federal Institute for Risk Assessment reviewed seven existing biomonitoring studies where trace amounts of glyphosate were found in human urine samples. The authors concluded that at the levels of glyphosate found, there is no concern for human health. After oral intake glyphosate is not metabolized significantly by humans and is rapidly excreted in urine. By measuring urine levels it is possible to calculate internal exposure levels. They concluded that realistic exposures are low and are well below the worst-case assumptions used by regulatory agencies.

Kathryn Z Guyton, Dana Loomis,Yann Grosse, Fatiha El Ghissassi,Lamia Benbrahim-Tallaa, Neela Guha,Chiara Scoccianti, Heidi Mattock,Kurt Straif, on behalf of the International Agency for Research on Cancer Monograph Working Group, IARC, Lyon, France Carcinogenicity of tetrachlorvinphos, parathion, malathion, diazinon, and glyphosate.  International Agency for Research on Cancer, Lyon, France. Published online March 20, 2014

"In March, 2015, 17 experts from 11 countries met at the International Agency for Research on Cancer (IARC; Lyon, France) to assess the carcinogenicity of the organophosphate pesticides tetrachlorvinphos, parathion, malathion, diazinon, and glyphosate. These assessments will be published as volume 112 of the IARC Monographs... There was limited evidence in humans for the carcinogenicity of glyphosate. Case-control studies of occupational exposure in the USA, Canada, and Sweden reported increased risks for non-Hodgkin lymphoma that persisted after adjustment for other pesticides. The AHS cohort did not show a significantly increased risk of non-Hodgkin lymphoma. In male CD-1 mice, glyphosate induced a positive trend in the incidence of a rare tumour, renal tubule carcinoma. A second study reported a positive trend for haemangiosarcoma in male mice. Glyphosate increased pancreatic islet-cell adenoma in male rats in two studies. A glyphosate formulation promoted skin tumours in an initiation-promotion study in mice..."

Jessica S. A. de Araujo, Isabella F. Delgado and Francisco J. R. Paumgartten Email author
Open Peer Review reports
A study in frog and chicken embryos, and reports of a high incidence of birth defects in regions of intensive GM-soy planting have raised concerns on the teratogenic potential of glyphosate-based herbicides. These public concerns prompted us to conduct a systematic review of the epidemiological studies testing hypotheses of associations between glyphosate exposure and adverse pregnancy outcomes including birth defects.
A systematic and comprehensive literature search was performed in MEDLINE, TOXLINE, Bireme-BVS and SCOPUS databases using different combinations of exposure and outcome terms. A case–control study on the association between pesticides and congenital malformations in areas of extensive GM soy crops in South America, and reports on the occurrence of birth defects in these regions were reviewed as well.
The search found ten studies testing associations between glyphosate and birth defects, abortions, pre-term deliveries, small for gestational date births, childhood diseases or altered sex ratios. Two additional studies examined changes of time-to-pregnancy in glyphosate-exposed populations. Except for an excess of Attention Deficit Hyperactivity Disorder - ADHD (OR = 3.6, 1.3-9.6) among children born to glyphosate appliers, no significant associations between this herbicide and adverse pregnancy outcomes were described. Evidence that in South American regions of intensive GM-soy planting incidence of birth defects is high remains elusive.
Current epidemiological evidence, albeit limited to a few studies using non-quantitative and indirect estimates and dichotomous analysis of exposures, does not lend support to public concerns that glyphosate-based pesticides might pose developmental risks to the unborn child. Nonetheless, owing to methodological limitations of existing analytical observational studies, and particularly to a lack of a direct measurement (urine and/or blood levels), or an indirect estimation of exposure that has proven valid, these negative findings cannot be taken as definitive evidence that GLY, at current levels of occupational and environmental exposures, brings no risk for human development and reproduction.

Attention deficit hyperactivity disorder Pesticides Birth defects Congenital anomalies Abortion Teratogenicity Reproductive toxicity Occupational exposure Agricultural workers Fecundity

A 2012 paper from Seralini/CRIIGEN/Uninversity of Caen/Auchan/Carrefour published in Food and Chemical Toxicology** has attracted a lot of attention to the topic of GM food safety. It was finally retracted by the journal in November 2013

A good readable explanation of this paper is here:

Ashley Ng. (2012) Genetically modified corn and cancer – what does the evidence really say?, The Conversation 25 September 2012, 6.18am AEST, 

The PR-spin used to manipulate the findings is analysed here:
R. Roush and D. Tribe (2012) Modifying the message: how tricks masked home truths about anti-GM science, The Conversation 25 September 2012, 6.18am AEST , 

For serious investigators of the questions posed by this CRIIGEN report, a series of letters to the Editor in response to the intitial G -E Seralini / CRIIGEN scientific article about rat feeing tests on GM maize are now available via the  links provided at the journal’s In-press page: and at this blog's CRIIGEN page. 

Exhibit 2.

GMO Pundit post on institutional affiliations of scientists who publish test results are listed in a GMO Pundit post hyperlinked here, which also has links to the original papers where available.

GMO Pundit post collecting independent published tests of GMO food and feed safety demonstrating Rosemary Stanton's claims on lack of tests are wrong. 

Exhibit 3.

[Citation list of 600 papers that test GM food safety in animal tests or directly and systematically measure or define safety parameters, such as allergenicity or potential toxin fingerprinting. Replaced by the now live GENERA database mentioned above.]

Exhibit 4

Baseline studies providing comparative data, and assessment of on variability and unexpected outcomes from conventional breeding.(separate webpage)