(CN) — The smallest changes in our ecosystem might go unnoticed but can still create significant consequences for the food chain. Ask the lowly water flea, which suffers significant DNA damage from even small amounts of the weed killer glyphosate over a long period of time.
The daphnia sit on the low end of the food chain, but as most school-age children learn, everything is connected in some way.
Researchers from the University of Birmingham who studied the daphnia revealed Tuesday that exposure to relatively low levels of the active ingredient in Roundup for a long period of time — levels deemed safe by the U.S. Environmental Protection Agency — caused DNA damage and other harmful impacts to a test group of plankton.
They published their findings in the journal Microbiome.
Besides the DNA damage, the researchers found glyphosate caused embryonic development failure, interfered with metabolic functions and harmed all the bacteria and protozoa that live in the gut.
Lead researcher Dr. Luisa Orsini from the University of Birmingham’s school of biosciences said research on Roundup has been controversial since it first appeared on the market as a commercial herbicide.
“Claims that it causes diseases and disorders ranging from cancer to autism stack up against industry-paid reports arguing that the product has no untoward effects,” Orsini said in a statement accompanying the study. “The problem is that much of the evidence is rooted in outdated toxicity tests which only look at the number of animals that die on exposure to extremely high concentrations of these chemicals. These tests also overlook the pathological effects arising from long-term exposure to low doses.”
For Roundup to alter an organism’s metabolism and other vital functions, especially in a species like plankton that is key to the food chain of freshwater ecosystems, means that the chemicals can harm more than just pests in a critical way, Orsini said in emailed comments.
That’s definitely alarming considering that the chemical reactions are on a molecular level that are constant across species, like humans.
The study was done in part with the U.K. Environment Agency, a nondepartmental public body that seeks to bring new standards for regulatory agencies when looking at chemicals and their impact on biodiversity.
Orsini said the research will be able to help identify the most harmful chemicals that make their way into the environment.
"We can't stop environmental contamination in one step, but by identifying the worst offenders, we can work with industrial partners in a more targeted and effective way,” said Orsini.
“Other studies have found some of the effects we document, but we take a comprehensive (system biology) approach revealing all implications of long-term exposures to low doses of the herbicide,” Orsini said by email. “We are not the only and will not be the last to show that Roundup is not safe.”
The sentiment is not a new one.
In 2015, the World Health Organization’s International Agency for Research on Cancer classified glyphosate as a probable human carcinogen. Roundup manufacturer Monsanto condemned the IARC report, pointing to regulatory bodies in the United States, Canada, the European Union, Japan, and Australia that reached a contrasting determination on glyphosate.
Monsanto — which is now owned by Germany-based chemical giant Bayer — has been in ongoing legal fights over its herbicide for years, which many plaintiffs blaming the weed killer for their cancers.
In 2019, a six-person jury awarded California resident Ed Hardeman $80 million, finding he developed non-Hodgkin lymphoma from long-term exposure to Roundup. Hardeman used the product on his lawn for years.
A federal judge later sharply reduced the jury’s award.
Talks of a settlement between Bayer and 4,000 other plaintiffs with similar claims stalled this past August, after lawyers representing half the plaintiffs told a federal judge they believed the company was trying to pull out of the $10 billion deal.
Bayer’s lawyer characterized the delay as “a slight hiccup” in negotiations.
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