From Green Right Now Reports

A photo of a rat suffering a tumor from the study of GMO corn.

Two groups of rats fed genetically altered corn suffered numerous health effects, including mammary, kidney and liver tumors that shortened their lives, according to a two year study of the effects of Round Up-Ready GMO corn by French researchers.

A control group of rats — those not fed any Round-up Ready GMO corn — lived longer  on average and developed far fewer tumors  than the affected rats eating GMO corn, according to the study published today in Food and Chemical Toxicology.

Pesticide Action Network of North America, currently battling to win disclosure labeling for GMO foods in California (Prop. 37), was quick to point to the findings, which the group called out as the first long-term animal study on the health effects of eating GMOs.

PANNA staff senior scientist Marcia Ishii-Eiteman, PhD, released this statement:

“The results of this new study are troubling and deserve further investigation. To date, pesticide and genetically engineered seed corporations have suppressed and restricted research into the efficacy and health impacts of their products. No doubt the study will draw opposition from Dow and Monsanto as these corporations rush to bring new genetically engineered crops to the market, especially 2,4-D corn. Industry insists that these products are safe, but they do so on the basis of studies that have never been repeated and have other major flaws. What [researcherGilles-Eric] Séralini’s work points to is the need to take very seriously, and more rigorously understand, the risks to human health posed by genetically engineered crops and foods.”

Dow and Monsanto, major makers of genetically crops and the pesticides they’re designed to work with, have maintained that the food grown with genetically modified seeds is fundamentally no different than other food.

“Numerous peer-reviewed scientific studies performed on biotech crops to date, including more than a hundred feeding studies, have continuously confirmed their safety, as reflected in the respective safety assessments by regulatory authorities around the world,” said Monsanto spokesman Tom Helscher said in a statement.

The team of scientists performing the 2-year rat study, however, noted cellular changes in many of the rats fed a certain variety of GMO corn (Monsanto’s R-tolerant NK603) as well as those that drank water dosed with Round Up to simulate a real life situation in which agricultural pesticide residues contaminate drinking water.

Genetically modified crops are designed to withstand pesticides in the belief that this will make them easier to grow for farmers who can spray pesticides without worrying about killing their crops.

Until recently, almost all GMO crops were designed to resist Monsanto’s Round Up (glyphosate), the most used pesticide on the planet. But some weeds have become resistant to the pesticide. Now biotech firms have submitted other versions for approval to the U.S. government, asking to be allowed to release crop seeds that will resist other pesticides such as 2,4-D.

Pesticide opponents, like PANNA, object to this development, arguing that not enough is known about GE foods to be able to tell if they’re safe.

GE seeds first entered the food system in the U.S. in the mid-1990s. Today, the majority of corn and soy grown in the U.S. is genetically modified.

The study released today found that rats fed diets that were 11 percent and 22 percent GMO corn developed more tumors, earlier in life, than rats in a control group.

The scientists found that in the control group 30 percent of the male rats and 20 percent of the female rats died spontaneously before the mean survival time for their species.

But in some GMO-fed groups 50 percent of the males and 70 percent of the females died before that point.

Some of the GMO-fed rats died very early. Two GMO-fed male rates died of enlarged kidneys a year before any male control rats died and one female rat died of a breast cancer 246 days before the first control, the researchers wrote.

Female rats that died earlier developed mammary tumors and male rats developed tumors in other organs, mainly the kidney and liver.

One aberration in the findings was that a group of rats fed a 33 percent ration of GMO corn did not develop tumors to the extent of those eating the smaller percentage rations.

This third group of rats, fed the highest level of GMO corn, inexplicably did not suffer the same degree of disease as those eating lower doses of GMO corn. In some cases, those rats lived as long as the controls.

Paul Towers, media director of the Pesticide Action Network North America, suggested that the pattern of tumors may not have appeared in that group of rats because of some sort of biological reaction.

“The body can react in unique and profound ways as a result of genetically modified food and pesticide exposure. Disturbed hormone and biochemical systems behave in non-linear ways — and more likely to appear as U or G curves on graphs.  The body may react initially but then may react less and less, as certain pathways may get turned off, which in turn can create new diseases,” Towers said.

Females appeared to be far more sensitive than the male rates to the presence of RoundUp in their drinking water, which shortened their lives compared to controls.

The research, lead by Dr. Seralini of Caen University in Normandy, was conducted using humane treatment methods, with the rats being euthanized if tumors exceeded 25 percent of their body mass.