Groundbreaking research on the health impacts of GMOs
Groundbreaking research on the health impacts of GMOs

Groundbreaking research on the health impacts of GMOs

3 min read
Written by Taarini Chopra

Genetically-Modified Organisms (GMOs) are in the news again. A team of French researchers has just released the results of a groundbreaking new study on the health effects of Monsanto’s GM Roundup Ready corn, NK603. The team, led by molecular biologist and endocrinologist Professor Gilles-Éric Séralini, studied the effect of feeding rats the herbicide resistant corn grown with and without the herbicide Roundup. The study was conducted over a two-year period (the average lifespan of laboratory rats), and this is what makes this research so significant — similar feeding trials have been conducted for 90-day periods in the past, but scientists have argued that this is insufficient to adequately observe long-term health impacts.

The results are startling. The researchers found that amongst the females, mortality of those being fed with the GM corn was 2–3 times higher than controls. Females also developed mammary tumors sooner and more often than males, and suffered from other organ and hormonal damage as well. Males developed severe kidney and liver damage and also developed tumors sooner and more frequently than controls. Most of these impacts were observed after the 90 day period when past studies have ended. The results are being published in the peer review journal Food and Chemical Toxicology.

The implications of the study are profound. The Canadian government does not conduct specific safety tests on GMOs. Monsanto’s NK603 corn, for instance, was approved for human consumption based solely on data submitted by the company itself. This data is not publicly available and scientists have not been given the opportunity to review its results. This current regulatory approval process goes starkly against the recommendations of the Royal Society’s Expert Panel on the Future of Food Biotechnology.

Perhaps unsurprisingly, given the history of attacks on scientists who have found negative impacts in GM feeding trials, the study has been the centre of much controversy. It has been criticized, for example, for using a breed of rats that are susceptible to tumors. However, this breed — Sprague-Dawley rats — are the most commonly used in feeding trial of this kind. In fact, they are the same breed used in Monsanto’s 13-week feeding trial of NK603, the results of which were also published in Food and Chemical Toxicology. Significantly, this study was conducted four years after the corn had been approved for human consumption in Canada.

The study underlines the inadequacies of current regulatory processes for GMOs, in Canada and around the world. Seralini and his team call for a review of all GM products that have already been approved and are on the market, both as food for humans, and in feed for animals. At the very least, their study highlights the need to conduct feeding trials that are sufficiently long to show accurate results, for every new GM crop, and for these results to be peer reviewed by independent experts. At a more fundamental level, however, it poses another important challenge to the claim that genetic modification is a safe and smart way to approach the future of our agricultural and food systems.

Seralini et al’s study can be found here:

For a summary of the study, a comparison with other studies, and its regulatory implications, visit:

A letter from independent scientists responding to criticisms of the study is here: