Elsevier, the publisher of the journal, Food and Chemical Toxicity, said it was pulling the study after a review of the raw data because it was inconclusive and did "not reach the threshold of publication," the Toronto Star reported.
The article, published last November, was taken up by anti-GM activists via social media, but it was panned by some scientists as well as Health Canada and The European Food Safety Authority, which called the paper scientifically unsound.
In the study, French professor Gilles-Eric Seralini of the University of Caen exposed rats for two years to herbicide-tainted water and fed them an unlimited diet of Roundup-resistant maize -- corn genetically modified to resist herbicide and marketed by Monsanto.
Seralini and colleagues said many of the female GM-fed rats grew massive mammary tumors and that the males suffered from liver damage; and that all died more quickly than rats in the control group fed a non-GM diet.
However, some scientists worldwide described the study as fundamentally flawed because the type of rat used in the study is well known to develop tumors -- especially with older rats and if fed an unrestricted diet.
The study was also criticized for using only a small control group and for not offering any explanation why females developed cancer but males appeared resistant.
In a statement emailed to the Star, Seralini threatened legal action as a result of the retraction and demanded the journal also retract an article on the same topic which he said was authored by Monsanto.
Meanwhile, Seralini's supporters doubled down and called the retraction unethical. They said the journal itself said it did not find evidence of misconduct or fraud and that the review panel had concluded only that the study was inconclusive, not incorrect, the Star said.