Study Shows Roundup and Fungicide Attract Bees, Then Kill Them

January 14, 2018 at 1:27 am

Scientists Worry About Implications for Global Food Supply


With hundreds of North American bee species on the verge of extinction, a new study brings us closer to the culprits —  fungicide and herbicide that attract them and then kill them.

-Researchers at the University of Illinois found that bees prefer sugar syrup laced with the popular herbicide glyphosate (aka Roundup) and/or the popular fungicide chlorothalonil over sugar syrup alone.

The team set up several feeding stations in an enclosure allowing the bees to choose either plain sugar syrup or sugar syrup laced with one of three fungicides or two herbicides at various concentrations.

While the bees avoided Roundup and chlorothalonil at high concentrations, they seemed to “have a taste for it” at low levels. They avoided the other fungicides and herbicide altogether.

The results of the study have “unsettling implications” for global food production, a scientist told Reuter’s.

“Bees are kind of like humans in that they sometimes like things that aren’t necessarily good for them,” said University of Illinois entomology professor May Berenbaum, who led the research.

The surprising finding follows other recent studies linking fungicides to declining global bee populations. One recent study, for example, found parallels between the use of chlorothalonil and the presence of a fungal parasite in bumble bees.

“People assume that fungicides affect only fungi,” said Berenbaum. “But fungi are much more closely related to animals than they are to plants. And toxins that disrupt physiological processes in fungi can also potentially affect them in animals, including insects.”

Fungicides are among the most prevalent contaminants of honey bee hives, and it is likely the bees themselves are bringing these pesticides into the colony through their food-collecting activities, the study’s authors wrote.

In the past, scientists have argued that bees may be less susceptible to toxic agricultural chemicals because they might detect and avoid them. But a 2015 study found that European honey bees and at least one species of bumble bee actually prefer food laced with insecticidal pesticides.

The scientists said the results are “worrisome,” because the bees’ exposure to fungicides may be reducing their ability to metabolize other harmful chemicals in the environment.

The United Nations recently announced an annual World Bee Day on May 20 to raise awareness of their importance and declining numbers.