Glyphosate, the world's most common weed killer, has caused significant concerns over its potential risk to human health, animals, and the environment for several decades. Earlier this month, a US court awarded a groundskeeper $289 million who claimed Bayer AG unit Monsanto's glyphosate-based weed-killers, including Roundup, gave him terminal cancer.
Now, a new report from PNAS alleges that glyphosate may be indirectly killing honey bees around the world, a threat that could potentially also leave a major mark on the global economy.
Brandnew research from The University of Texas at Austin shows that bees exposed to glyphosate, the active ingredient in Roundup, lose critical bacterial in their guts and are more susceptible to infection and death from harmful bacteria.
The report titled "Glyphosate perturbs the gut microbiota of honey bees," was published in the Proceedings of the National Academy of Sciences of the United States of America (PNAS) on September 24. It provides enough evidence that glyphosate could be seen as the contributing factor to the rapid decline of honey bees around the world, otherwise known as Colony Collapse Disorder (CCD), a phenomenon that occurs when the majority of worker bees in a colony disappear and leave behind the queen.
“We need better guidelines for glyphosate use, especially regarding bee exposure, because right now the guidelines assume bees are not harmed by the herbicide,” said Erick Motta, the graduate student who led the research, along with professor Nancy Moran.
“Our study shows that’s not true.”
UT News of The University of Texas at Austin says that glyphosate interferes with an important enzyme found in plants and microorganisms, but not in animals, it has long been assumed to be nontoxic to animals, including humans and bees. However, the latest study reveals that by altering a bee’s gut microbiome — the ecosystem of bacteria living in the bee’s digestive tract, including those that protect it from harmful bacteria — glyphosate jeopardizes its ability to fight infection.
For this study, scientists exposed honeybees to glyphosate at normal levels found on farms. The researchers painted the bees' backs with colored dots so they could be tracked and later recaptured. Three days later, they saw that the honeybees exposed to glyphosate suffered a significant loss of bacteria in their guts and were more susceptible to infection and death from harmful bacteria.
“Studies in humans, bees and other animals have shown that the gut microbiome is a stable community that resists infection by opportunistic invaders,” Moran said. “So if you disrupt the normal, stable community, you are more susceptible to this invasion of pathogens.”
In recent times, US beekeepers have reported a massive loss of bees or CCD. Millions of bees mysteriously disappeared, leaving farms with fewer pollinators for crops. Officials have been baffled, and the media has been quite about the bee population collapse. Explanations for the phenomenon have included exposure to pesticides or antibiotics, habitat loss, and bacterial infections. The latest study now adds herbicides to the list as a possible contributing factor.
“It’s not the only thing causing all these bee deaths, but it is definitely something people should worry about because glyphosate is used everywhere,” said Motta.
And that, researchers, believe, is evidence that glyphosate might be contributing to the collapse of honeybees around the world.
The Western honeybee, the world's premier pollinator species, has been in high demand for its services on fruit, nut, and vegetable farmers.
Among the nuts, almond growers have the largest need for bee pollination. Bee pollination is worth $15 billion to the US farming industry.
Any sharp change in global bee populations could affect the beef and dairy industries. Bees pollinate clover, hay, and other forage crops. As the bee population dwindles, it increases the cost of feedstock. That forces inflation into beef and milk prices at the grocery store and ultimately hurts the American consumer. This could then lead to increased imports of produce from foreign countries where bee populations are healthy, further widening the trade deficit. Couple this with the current trade war and this particular "black swan" - or rather "black bee" - problem, may be just the tipping point that finally forces the US economy to catch down to the rest of the world.