A bizarre study by French researchers claiming ill effects on laboratory rats fed genetically modified corn and given water spiked with herbicide has been rejected by American scientists who questioned the motives and methods of the authors.

“This study appears to be without scientific merit,” said Dr. Martina Newell-McGloughlin, director of the International Biotechnology Program at the University of California/Davis. “The problem here appears to be with the experimental design,” she said. “Whether it was deliberately devised to attain the desired outcome remains to be seen.”

“This is not an innocent scientific publication,” Dr. Bruce M. Chassy, professor emeritus of food science at the University of Illinois, said.  “It is a well-planned and cleverly orchestrated media event.  The study was designed to produce exactly what was observed and it was deliberately allowed to continue until grotesque and fear-evoking tumors developed.  The way the study was conducted, including the treatment of the animals, especially those who developed tumors as these rats are known to do, raises serious ethical concerns and profound questions of possible scientific misconduct.”

“The purpose of the study was not to produce new scientific information but rather was to negatively influence public opinion of GM crops,” Chassy added.  “This makes a mockery of science.  It is a shame that the media and the journal that published the study were so uncritical.”

The study was led by Gilles-Eric Seralini, whose book attacking biotechnology was recently re-issued.  The study claimed that rats fed a steady diet of feed made from biotech corn developed tumors.  In addition, the drinking water of the rats was continuously spiked with glyphosate, the active ingredient in many broad spectrum herbicide products.  Glyphosate has a long history of safe use in more than 130 countries around the world and favorable environmental characteristics.  It binds tightly to most soils making it unlikely to move to groundwater and degrades over time in soil and natural waters.

Scientists pointed out that numerous studies in the scientific literature attest to the fact that the particular stock of rats used in the study, lab animals known as the “Sprague-Dawley” type, are prone to develop tumors before the age of two.  The Seralini study ran for about two years.

Seralini touted the study as the first long-term feeding study ever conducted, but Dr. Newell-McGloughlin pointed out that in fact the results of numerous long-term studies have been published with none of the results claimed by Seralini.

Lack of sound science

“These studies have been carried-out using rats and other animals by scientific researchers from all over the world,” she said.  “No unexpected adverse effect has been reported.”

The design of the Seralini experiment was unusual and statistical controls lacking, scientists said.

“The incidence of tumors in rats reported over many studies and many years is the same as that reported in the paper,” Dr. Newell-McGloughlin said.  “This study does not provide any greater evidence of statistical significance above random occurrence for these animals.”

“The bottom line is, despite numerous studies in the peer-reviewed scientific literature, and substantial experience with humans and animals around the world consuming biotech crops for over 15 years, there has not been a single substantiated case of negative outcomes or a single documented health problem,” she said. 

Seralini’s previous work has been rejected by European experts.  The European Food Safety Authority (EFSA) examined a previous animal feeding study paper by Seralini and others and said: “Following a detailed statistical review and analysis by an EFSA Task Force, EFSA’s GMO Panel has concluded that this re-analysis of the data does not raise any new safety concerns.”

“The statistical analysis made by the authors of the paper did not take into account certain important statistical considerations,” the EFSA panel noted.  “The assumptions underlying the statistical methodology employed by the authors led to misleading results ... EFSA considers that the paper does not present a sound scientific justification in order to question the safety” of the biotech corn being studied.