A long term feeding study has found that rats fed a diet that contains a proportion of GM maize or minute residues of Roundup has resulted in significantly higher increases of cancers, kidney disease, liver damage and other negative health effects.
The study led by Professor Gilles-Eric Seralini and published in Food and Chemical Toxicology has found that both the GM maize and Roundup acted as endocrine disrupters and resulted in the females dying 2 - 3 times more than the control animals.
The females that were fed either GM maize or non GM maize with minute roundup residues, developed large mammary tumors almost always more often than and before controls. All the non control females, except for one that had ovarian cancer, had mammary hypertrophies (enlarged mammary glands) and in some cases hyperplasia with atypia (nodules in the mammary glands).
The pituitary gland was the second most disabled organ and the sex hormonal balance was modified in females fed with the GMO and Roundup treatments.
The treated males presented 4 times more large palpable tumors than controls and these occurred up to 600 days earlier. The treated males had liver congestions and necrosis that were 2.5 - 5.5 times higher than the controls as well as marked and severe kidney nephropathies that were also generally 1.3 - 2.3 greater than the controls.
This study was the first 2 year feeding trial conducted on rats designed to see the effects of GM over an animal's lifetime. Currently, no regulatory authority requests mandatory chronic animal feeding studies to be performed for edible GMOs. However, several studies consisting of 90 day rat feeding trials have been conducted by the biotech industry even though there is no requirement to do this.
Regulatory authorities use a basic chemical analysis of a GM variety and compare this with it closest non GM variety. If this chemical composition is much the same, the GM variety is declared as substantially equivalent and suitable for uncontained commercial release.
The comparison of the chemical composition of the GM maize used in this study (NK603) revealed no particular difference and consequently it was classified as substantially equivalent.
Similarly a 90 day feeding trial showed no significant differences between the controls and the rats fed the GM maize variety.
The results of the 2 year feeding study show that the current regulatory system for approving GM crops for consumption are inadequate for assessing the effects of eating these foods over a normal lifetime.
Minute Roundup Residues cause Ill Health
The other result that should be of great concern is the effect of minute Roundup residues.
No regulatory authority requests mandatory chronic animal feeding studies to be performed on the actual formulation of an agricultural chemical. The testing is done on the pure laboratory grade version of the active ingredient and not on the actual product that is used. In the case of Roundup the tests used by regulatory authorities to approve its use have been conducted on glyphosate and not on Roundup.
Roundup is composed of glyphosate and several other chemicals that are needed to make it work as an herbicide. Seralini et al stated: 'It is important to note that glyphosate is only able to efficiently penetrate target plant organisms with the help of adjuvants present in the various commercially used R [Roundup] formulations (Cox, 2004). When R residues are found in tap water, food or feed, they arise from the total herbicide formulation, which is the most commonly used mixture in agriculture; indeed many authors in the field have strongly emphasized the necessity of studying the potential toxic effects of total chemical mixtures rather than single components (Cox and Surgan,2006; Mesnage et al., 2010; Monosson, 2005). Even adjuvants and not only glyphosate or other active ingredients are found in ground water (Krogh et al., 2002), and thus an exposure to the diluted whole formulation is more representative of an environmental pollution than the exposure to glyphosate alone in order to study health effects.'
In order to determine if the health effects were caused by the GM maize or by Roundup the study had 3 treatments. GM maize treated with Roundup as part of the normal cultivation practice, GM Maize cultivated without Roundup and non GM maize where minute amounts of Roundup were added. All three treatments resulted in negative health effects compared to the control that was non GM maize without roundup. This showed that both Roundup and the GM Maize disrupted the endocrine systems of the treated rats.
Three groups of rats were fed with the control diet of non GM maize and drinking water that supplemented with different amounts of Roundup (R). These were at the level of 0.1 ppb of R (50 ng/L of glyphosate which is the contaminating level of some regular tap waters, 0.09% of R (400 mg/kg, the US MRL of glyphosate which is the residue level in some GM feeds) and 0.5% of R (2.25 g/L, half of the minimal agricultural working dilution).
All the treatment groups had a range of negative health effects however the groups treated with non GM Maize and Roundup had the highest rates of cancers, with 80% of the rats being affected. 'The R [Roundup] treatment groups showed the greatest rates of tumor incidence with 80% of animals affected with up to 3 tumors for one female, in each group.'
The Study authors noted that Roundup caused endocrine disruption and cell damage in the rats and that this was consistent with earlier studies. 'Indeed, it has been demonstrated that R [Roundup] concentrations in the range of 103 times below the MRL [Maximum Residue Limit] induced endocrine disturbances in human cells (Gasnier et al., 2009) and toxic effects thereafter (Benachour and Seralini, 2009), including in vivo (Romano et al., 2012). After several months of consumption of an R-tolerant soy, the liver and pancreas of mice were affected, as highlighted by disturbances in sub-nuclear structure (Malatesta et al., 2008a, 2002a,b).'
This study raises serious concerns about the current regulatory systems for both GMOs and agricultural chemicals. The variety of GMO maize studied by Seralini et al. had passed the standard 'substantially equivalent' test used by regulatory authorities to approve the commercial release of GMO crops. It had further been assed as safe by the non mandatory 90 day feeding trail.
However the results of the 2 year trial to assess a lifetime of exposure showed significant negative health effects.
Similarly when Roundup was tested at levels 1000 times lower that the current MRLs and at levels equivalent to those found in the drinking water in many areas, 80% of the treated animals developed cancer and other health problems.
The data in this study shows that the current regulatory systems for both GMOs and agricultural chemicals are inadequate and need to be urgently reformed. It shows that all GMOs that are used for food purposes need to be subjected to lifetime feeding trials to assess their safety. The data further shows that the actual formulations of agricultural chemical need to be tested for lifetime exposure to assess the safety of their residues in a food, water and air.
There are around 7,200 formulated chemical products that have been approved for use in agriculture in Australia and not one of these formulations has been tested, even using the current testing methodologies. Only the active ingredient has been tested, not the formulation of chemicals that are used and whose residues are commonly found in our food, water and air.
Our regulatory authorities have a legal duty of care to ensure the safety of people exposed to the chemicals and GMOs that they approve for commercial use. They should be acting on the latest scientific evidence rather than relying on methodologies that numerous studies have shown to be inadequate.
Séralini, G.-E., et al. Long term toxicity of a Roundup herbicide and a Roundup-tolerant genetically modified maize. Food Chem. Toxicol. (2012),