Science & Nutrition

Pesticide toxicity vastly understated, claims new Séralini study

Last updated the 31-Jan-2014 at 15:58 GMT - By Oliver Nieburg+
 A new study by French scientist Gilles-Eric Séralini says that pesticides are more toxic to humans than recognised levels.
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Major pesticides are more toxic to humans than their declared active principles, according to a new study by divisive French scientist Gilles-Eric Séralini.

The study due for publication in BioMed Research International questions how acceptable daily intakes (ADI) for pesticides are measured. It claims that ADIs exclude adjuvants in the pesticides that have the potential to seriously amplify the toxicity of the active principle in commonly used pesticides.

“Adjuvants in pesticides are generally declared as inerts, and for this reason they are not tested in long-term regulatory experiments. It is thus very surprising that they amplify up to 1000 times the toxicity of their active principle in 100% of the cases where they are indicated to be present by the manufacturer,” said the study.

Definition of adjuvants ‘nonsense’

It continued: “The definition of adjuvants as ‘inerts’ is thus nonsense; even if the US Environmental Protection Agency has recently changed the appellation for “other ingredients”, pesticide adjuvants should be considered as the first toxic "active" compounds.”

To reach these conclusions, the researchers tested the toxicity of nine commonly used pesticides, comparing active principles and their formulations on three human cell lines (HepG2, HEK293 and JEG3).

“Despite its relatively benign reputation, Roundup was by far the most toxic among the herbicides and insecticides tested. Most importantly, 8 formulations out of 9 were several hundred times more toxic than their active principle.”

‘Huge economic interests’

The study suggested that the standard to measure ADIs was motivated by financial gain.

“This inconsistency between scientific fact and industrial claim may be attributed to huge economic interests, which have been found to falsify health risk assessments and delay health policy decisions.”

FoodNavigator contacted The European Food Safety Authority (EFSA), which is responsible for scientific reviews on ADIs. The organization said it was aware of the new paper and would review it in due course.

ECPA shuns findings

The European Crop Protection Association (ECPA) said in a statement that the study did not meet basic 21st century standards for scientific enquiry and was therefore irrelevant for the safety evaluation of pesticide products on human health.

“The testing model used by the authors is inappropriate for drawing any conclusions regarding real life toxicity relevant to humans.  The authors’ direct exposure of in vitro cultured human cell lines to pesticide formulations circumvents the body’s most effective natural protective barrier, the skin, and does not reflect relevant in vivo exposure conditions which take into account the absorption, distribution, metabolism and excretion of a product within the body. “

It added that the pesticides evaluated in the study were already approved by the EU on the basis of in vivo toxicity studies and said adjuvant co-formulants were already part of the EU regulatory assessment.

Calls to reinstate rat study

French researcher Professor Gilles-Eric Séralini published a study in September 2012 linking Monsanto's GM maize and Roundup products to cancer in rats. The finding was heavily criticised and the Elsevier journal Food and Chemical Toxicology later moved to withdraw the research claiming it was not ‘scientifically sound'. EFSA also said the study failed to meet scientific standards.

This week 41 scientists and experts demand reinstatement of the rat study.  In a separate initiative from December 2013, over 860 scientists worldwide condemned the retraction in an open letter and announced a boycott of Elsevier journals.

BioMed Research International (In Press)
‘Major pesticides are more toxic to human cells than their declared active principle’
Authors: Mesnage R., Defarge N., Spiroux de Vendômois J, Séralini G.E.

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