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'Worrying' new research links popular weedkiller to fatty liver disease


A new study has linked the commonly used glyphosate-based Roundup herbicide with non-alcoholic fatty liver disease in rats at 'very low' doses.

The authors of the study say it is unique in that it is the first to show a causative link between consumption of Roundup at a real-world environmental dose and a serious disease condition.

The study, by Scientific Reports, an online, open access journal from the publishers of Nature used cutting edge profiling methods to describe the molecular composition of the livers of female rats administered with an extremely low dose of Roundup weedkiller over a two-year period.

The dose of glyphosate from the Roundup administered was thousands of times below what is permitted by regulators worldwide.

The study revealed that these animals suffered from non-alcoholic fatty liver disease (NAFLD). Non-alcoholic fatty liver disease (NAFLD) is the build up of extra fat in liver cells that is not caused by alcohol. It is normal for the liver to contain some fat. However, if more than 5% - 10% percent of the liver’s weight is fat, then it is called a fatty liver (steatosis).

NAFLD affects up to 25% of people in the United States.

Symptoms of NAFLD include fatigue, weakness, weight loss, loss of appetite, nausea, abdominal pain, spider-like blood vessels, yellowing of the skin and eyes (jaundice), itching, fluid build-up and swelling of the legs and abdomen, and mental confusion.

NAFLD can progress to the more serious condition, non-alcoholic steatohepatitis (NASH). NASH causes the liver to swell and become damaged.


Dr Michael Antoniou, of King’s College London, who lead the research said the findings of the study are 'very worrying' as they demonstrate for the first time a causative link between an environmentally relevant level of Roundup consumption over the long-term and a serious disease – namely non-alcoholic fatty liver disease.

“Our results also suggest that regulators should reconsider the safety evaluation of glyphosate-based herbicides.”

The new results demonstrate that long-term consumption of an ultra-low dose of Roundup at a glyphosate daily intake level of only 4 nanograms per kilogram of bodyweight per day, which is 75,000 times below EU and 437,500 below US permitted levels, results in NAFLD.

Regulators worldwide tend to accept toxicity studies in rats as indicators of human health risks, so the results of this study may have serious implications for human health.

'Bad Science'

In responce, Monsanto has said that the study has been rejected by the wider scientific community due to a flawed scientific approach.

"This latest study was conducted by infamous researchers, including Robin Mesnage and Gilles-Eric Seralini, who have a history of using bad science to link Monsanto’s products to health issues.

"Similar past studies from these researchers were classified as ‘pseudoscience’ and lacking ethical conduct by the international science community," it said.

Online Editors