CRIIGEN 2012 study: Long-term health impacts of GM and Roundup

On 19 September the independent team at the CRIIGEN lab at the University of Caen published the findings of a two-year feeding trial of rats using Monsanto’s NK603 Roundup tolerant maize and Roundup (the brand name weedkiller containing glyphosate many GM crops are designed to resist).

The work sparked a storm in scientific, political and regulatory circles worldwide. This page outlines the findings of the study and the fallout in 2012. There is a separate page with information about the controversial retraction of the study in 2013.

Study findings and attacks on the research team

The research found:

  • Death rates in rats fed GM maize was 70% in females and 50% in males compared to the 20% and 30% in control animals.
  • Female death rates were 2-3 times higher than controls.
  • Mammary tumours were the most common cause of death in females.
  • Treated male rats showed increased liver and kidney problems.

The researchers suggest the observed effects are due to the hormone-disrupting effects of Roundup and the impacts on metabolism of the GM trait that makes the maize tolerant to Roundup.

Feeding trials used to assess the safety of GM crops and herbicides, such as Roundup, do not normally last longer than 90 days, and GM Freeze and others have for many years called for more thorough safety tests to be performed to determine the long-term effects of eating GMOs and the chemicals used with them.

The study has been attacked by pro-GM voices, and Monsanto's response is here, but GM Watch has a good summary of the players here. The team has defended its work, and an international petition is inviting support from other scientists. The European Network of Scientists for Social and Environmental Responsibility (ENNSER) issued a statement on 5 October discussing Questionable Biosafety of GMOs, Double Standards and, Once Again, a "Shooting-the-Messenger" Style Debate.

Monsanto's GM Roundup Ready maize currently enters the UK mainly as animal feed from North and South America. Meat, milk and dairy products from GM-fed animals are not labelled to show where GM feed is used, and GM Freeze is pressing supermarkets to use voluntary non-GM fed labels to help shoppers avoid unwittingly adding GM to their shopping trolleys.

You can learn more about this study by:

  1. EXCLUSIVE. Yes, GMOs are poisonous! (this is the original breaking story in translation) - Le Nouvel Observateur, 19 September (French original here)
  2. Monsanto Roundup weedkiller and GM maize implicated in 'shocking' new cancer study - The Grocer, 19 September
  3. First Peer Reviewed Lifetime Feeding Trial Finds "Safe" Levels Of GM Maize And Roundup Can Cause Tumors And Multiple Organ Damage - HeraldOnline, 19 September
  4. French study finds tumours in rats fed GM corn - Reuters, 19 September
  5. France to probe cancer link to genetically modified corn - Herald Sun, 20 September
  6. Russia suspends import and use of American GM corn after study revealed cancer risk - Daily Mail, 25 September
  7. Study linking GM maize to cancer must be taken seriously by regulators - Guardian environemnt blog, 28 September

Learn about the controversial retraction of the study in 2013 here.

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ACT NOW: Please visit our action page for advice on writing to your MP today demanding more thorough safety testing of GM food and feed.