Insecticide in Iowa waters linked to bee deaths in some studies

More study needed, area beekeepers say

MOUNT VERNON — Research by the U.S. Geological Survey recently found widespread concentrations of a type of insecticide in Iowa streams, one that some other studies have linked to declines in honey bee populations.

They’re called neonicotinoids, or simply “neonics,” and they’re used widely as seed treatments in Midwest crops, according to Dana Koplin, one of the USGS researchers involved with the research.

While the USGS did find these compounds in Iowa waterways, there’s still a question of whether that discovery is in any way linked to the losses beekeepers have seen in Iowa in recent years. Either way, beekeepers we spoke with told us there’s science that proves neonics are bad for bees.

For Adam Ebert, owner of Ebert Honey, beekeeping is in his blood.

“It began when an elderly gentleman who could no longer lift bee boxes gave my dad two hives, and that was the year I was born,” Ebert told us.

Since then, the job has become more challenging. Lately, he’s seen a 25 to 40 percent yearly loss in his hives. In addition to a bee-killing mite, and increasingly harsh winters, Ebert said many beekeepers are now voicing concerns over neonicotinoids.

“Most of the corn and soybeans in the state are treated with pesticides, and many of them are insecticides,” and many of those are neonics, said Koplin. He started measuring neonic concentrations in Iowa streams and rivers early last year, to find out when and how they’re getting into the water.

“That key sensitive time is during and just after planting, when things are freshly being used and you get that rainfall on top of that, and you get those pulses going into the streams,” Koplin explained.

After they get into the water, however, Kolpin said their potential environmental impacts become less clear.

“In Europe, they put a three-year moratorium on their use until science kind of catches up and determines if these compounds are safe enough to use,” Koplin said.

Ebert said there is research linking neonics to paralysis and nervous system damage in bees, but it’s still difficult to say what comprises a lethal dose.

“Perhaps, sublethal doses cause bees to not be able to get back home,” Ebert told us.

But to figure out if the neonics found in Iowa waters are the cause of declining bee populations, or only a symptom, Kolpin said it will take more work.

“Work with our internal biologists and other toxicologists,” he said, “to really understand, what are the consequences of the parts-per-trillion levels we’re seeing in streams.”

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