The EU's food safety agency definitively rejected Wednesday a bombshell French report linking genetically modified corn to cancer, saying it failed to meet "acceptable scientific standards."
"Serious defects in the design and methodology of a paper by Seralini et al. mean it does not meet acceptable scientific standards," the European Food Safety Authority said in a statement.
"Consequently it is not possible to draw valid conclusions about the occurrence of tumours in the rats tested," the agency said.
EFSA, which reviews the use and authorisation of GMOs (Genetically Modified Organisms), added that it "finds there is no need to re-examine its previous safety evaluations of NK603," the genetically modified maize developed by US agribusiness giant Monsanto.
That same conclusion had been reached in separate and independent assessments of Gilles-Eric Seralini's work carried out in six European Union nations, the agency added.
Seralini's research team at France's University of Caen issued a report in September concluding that rats fed on NK603 corn, or exposed to one of Monsanto's weedkillers used with the corn strain, and containing glyphosate, developed tumours.
The study's conclusions, illustrated by horrific images of cancer-ridden rats, caused worldwide alarm.
NK603 is resistant to the Monsanto herbicide Roundup, enabling farmers to use the weedkiller just once in the crop's life-cycle and make substantial savings.
Seralini and his team said their experiment in GM food was the first to follow rats through their lifespan, as opposed to just 90 days.
But many experts quickly questioned its methodology, results and relevance to humans.
The EU agency said its final assessment took into consideration evaluations carried out in Belgium, Denmark, France, Germany, Italy and the Netherlands.
"EFSA noted the emergence of a broad European consensus," it said, stating that the six countries too found Seralini's conclusions "were not supported by the data presented in the study."
It listed weaknesses of the French study as "unclear study objectives, the low number of rates used in each treatment group, a lack of detail on the feed and treatment formulation, key information missing on the statistical methods employed."
In a first response last month, EFSA dubbed Seralini's study "inadequate" and urged him to provide additional information before a second, final review was completed.
But the scientist responded that he would not give EFSA additional information until it first detailed the basis of its own assessment.
"It is absolutely scandalous that (EFSA) keeps secret the information on which they based their evaluation" of NK603 and the pesticide, he said at the time.
"In any event, we will not give them anything. We will put the information in the public domain when they do," Seralini told AFP.
His research group, Criigen, this month issued a list of almost 200 scientists from more than 30 countries who back the study.
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