Weed killer Roundup® may cause convulsions in animals

In a recent report, the Centers for Disease Control and Prevention (CDC) has provided evidence that over 80 percent of urine samples from children and adults in the United States contained the herbicide glyphosate, which is the main ingredient of Roundup®, the world’s most commonly used weed killer. Now, a team of researchers led by Florida Atlantic University (FAU) has found that the use of Roundup® can affect animals’ nervous system, leading to convulsions and other health hazards.

“It is concerning how little we understand the impact of glyphosate on the nervous system,” said study lead author Akshay S. Naraine, a doctoral student in Integrative Biology and Neuroscience at FAU. “More evidence is mounting for how prevalent exposure to glyphosate is, so this work hopefully pushes other researchers to expand on these findings and solidify where our concerns should be.” 

The researchers used C. elegans, a soil-dwelling roundworm, to test both glyphosate alone and the U.S. and U.K. formulations of Roundup® from two different time periods – before and after the U.K.’s ban on polyethoxylated tallowamine (POEAs) from 2016. The investigation revealed that all of these substances increased seizure-like behavior in roundworms, providing significant evidence that glyphosate targets GABA-A receptors (which are fundamental for locomotion and sleep and mood regulation in humans). These effects were observed at significantly less levels of glyphosate than those deemed safe by the Environment Protection Agency (EPA).

“The concentration listed for best results on the Roundup® Super Concentrate label is 0.98 percent glyphosate, which is about five tablespoons of Roundup® in one gallon of water. A significant finding from our study reveals that just 0.002 percent glyphosate, a difference of about 300 times less herbicide than the lowest concentration recommended for consumer use, had concerning effects on the nervous system,” Naraine reported.

“Given how widespread the use of these products is, we must learn as much as we can about the potential negative impacts that may exist,” added study senior author Ken Dawson-Scully, a neuroscientist at the Nova Southeastern University. “There have been studies done in the past that showed the potential dangers, and our study takes that one step further with some pretty dramatic results.”

Further research is needed to clarify how chronic exposure and accumulation of glyphosate may lead to neurodegenerative diseases such as Parkinson’s.

“As of now, there is no information for how exposure to glyphosate and Roundup® may affect humans diagnosed with epilepsy or other seizure disorders. Our study indicates that there is significant disruption in locomotion and should prompt further vertebrate studies,” Professor Dawson-Scully concluded.

The research is published in the journal Nature Scientific Reports.

In response to this study, Bayer has released the following statement: “It is important to note that this research was conducted with worms. Research with worms does not meet the scientific standards necessary to predict effects on humans or other mammals for the purposes of a pesticide safety assessment.”

“Safety scientists at regulatory agencies around the world have reviewed glyphosate and the other ingredients in glyphosate-based herbicides and specifically considered whether they can harm the nervous system based on data from high dose studies in mammals, not worms.”

“Scientists that have reviewed all of the available data have concluded that neither glyphosate nor the other ingredients in glyphosate-based herbicides will harm the nervous system at doses much greater than what any human would be exposed to.”

—

By Andrei Ionescu, Earth.com Staff Writer