Glyphosate and the glyphosate-based herbicide Roundup disrupt the gut microbiome by the same mechanism by which the chemical acts as a weedkiller, and these effects happen even at low doses that regulators claim to be safe, a newly published study has found.

The new study was conducted by an international team of scientists based in London, France, Italy, and the Netherlands, led by Dr Michael Antoniou of King’s College London. It is published today in the journal Environmental Health Perspectives.

The study is the first to describe a mechanism by which glyphosate and Roundup affect the function of the gut microbiome (bacterial populations and biochemical function) in rats, which are the standard model that regulators use for assessing the human health risks of chemicals. The study found that glyphosate disrupts the rat gut microbiome through the same route by which it kills weeds – inhibition of the shikimate biochemical pathway.

Humans and animals do not have the shikimate pathway (pg. 23), enabling industry and regulators to claim that glyphosate is nontoxic to humans. However, some strains of gut bacteria do have this pathway, leading the researchers on the new study to investigate whether Roundup and glyphosate could affect the gut microbiome. Imbalances in gut bacteria have been linked to an ever-growing array of diseases, including cancer, Type 2 diabetes, obesity, and depression.

The researchers found that both Roundup and glyphosate affected the microbiome at all doses tested, causing shifts in bacterial populations.

Moreover, by measuring molecular composition profiles in the blood and gut, the new study also showed that the Roundup formulation tested (MON 52276, marketed as Roundup BioFlow) was more disruptive than glyphosate alone. Rats consuming this Roundup formulation developed signs of oxidative (reactive oxygen) stress in their blood, which was not as evident with glyphosate alone.

This is a concern as oxidative stress can not only damage cells and organs, but also DNA, which can lead to serious disease such as cancer.

“Safe” doses not safe after all

In the study, glyphosate and Roundup (at the same glyphosate-equivalent dose) were fed to the rats in their drinking water to give a daily intake of 0.5 mg/kg, 50 mg/kg and 175 mg/kg of body weight per day (mg/kg bw/day), which respectively represent the EU acceptable daily intake (ADI), the EU “no observed adverse effect level” (NOAEL), and the U.S. NOAEL.

The ADI is the dose that regulators judge safe to ingest on a daily basis over a lifetime and the NOAEL is the dose that is claimed to show no visible adverse effects in industry tests submitted to regulators.

The study reveals those assumptions to be unreliable, in that the doses tested were found to cause adverse effects. Some of these effects were found at all doses, though in general, stronger effects were seen with Roundup than from glyphosate, especially on the blood.

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Via https://childrenshealthdefense.org/defender/roundup-weedkiller-disrupts-gut-microbiome-new-study