Researchers Uncover Multiple Sources of Bias in GMO Risk Assessments

The GMO risk assessment process claimed to protect the public acts instead to protect industry. Scientists Hartmut Meyer and Angelika Hilbeck reviewed Monsanto’s rat toxicology studies on GM maize NK603 and identified flawed methods that bias results in industries’ favor. One such method is the use of multiple unrelated ‘pseudo-controls’ that make aberrant results look normal. Pseudo-controls have become a common component of other GMO risk studies, not only feeding trials. Meyer and Hilbeck also found that GMO studies routinely fail to use procedures like randomized selection of animals and blinded experiments, both of which guard against biased and inaccurate results. When they examined the written judgements of government-appointed regulators, however, Meyer and Hilbeck found such methodological flaws were criticized only when studies reported results unfavorable to industry. Thus systematic bias originates from both flawed GMO research methodology and the double standards of GMO regulators.

Meyer and Hilbeck’s recent analysis adds further weight to the argument that widespread industry-favorable bias exists within the GMO risk assessment process (from research, to publication, to regulation).


Meyer, Hartmut, and Angelika Hilbeck. “Rat feeding studies with genetically modified maize – a comparative evaluation of applied methods and risk assessment standards.” Environmental Sciences 25 (2013): 33. [This reference has been added to the Bioscence Resource Project Biotechnology Resource Page.]

Creating Unbiased and Scientific GMO Risk Assessment Procedures:

Heinemann, Jack A., Sarah Zanon Agapito-Tenfen, and Judy A. Carman. “A Comparative Evaluation of the Regulation of GM Crops or Products Containing dsRNA and Suggested Improvements to Risk Assessments.Environment international 55 (2013): 43-55.

Hilbeck, Angelika, et al. “Environmental risk assessment of genetically modified plants-concepts and controversies.” Environmental Sciences Europe 23.1 (2011): 1-12.

Freese, William, and David Schubert. “Safety Testing and Regulation of Genetically Engineered Foods.” Biotechnology and Genetic Engineering Reviews 21.1 (2004): 299-324.

The political origins of unscientific and industry-friendly regulatory policies in the U.S.:

Pelletier, David L. “FDA’s regulation of genetically engineered foods: Scientific, legal and political dimensions.Food policy 31.6 (2006): 570-591.

Allison Wilson, PhD, Science Director, The Bioscience Resource Project