Fresh Ideas: Pesticides: The allure and danger of nicotine on honeybees

Since the European Commission in 2013 banned the use of certain neonicotinoids (chemicals related to nicotin) on flowering plants because of their “high acute risks” to bees as determined by the European Food Safety Authority, it has been sued by the two major producers of neonicotinoids, Syngenta (Swiss) and Bayer CropScience (German).

The legal case still is pending, but in the meantime, the European Academies Science Advisory Council has published more than 100 peer-reviewed papers, and here are a few of their conclusions:

Pesticides have “severe effects” on a range of organisms, including insects categorized as predatory, such as parasitic wasps and ladybugs. These “predatory” types serve as pollinators as well as nature’s pest controls.

Pesticides also have a “severe effect” on earthworms which improve soil productivity.

A new, unexpected and disturbing finding, this one conducted by British and Irish researchers, concludes both honeybees and bumblebees, if given a choice between plain sugar water and sugar water laced with neonicotinoid pesticides, prefer the one with the neonicotinoid — even though the bees ate less and were more likely to die.

There had been theories suggesting bees would avoid pesticide-treated plants because they would “taste bad,” but additional studies by the researchers showed bees were unable to taste the pesticide, but consume it anyway because it affected their brains.

We have already known these pesticides cripple honeybees’ memories and navigational abilities because they can not find their way home. The idea, however, bees are just as vulnerable to nicotine’s “addiction” as we humans are, is unsettling, as well as (maybe) surprising.

Another recent study published in the Swedish journal Nature has found both wild bees and bumblebees foraging in pesticide treated fields are less likely to reproduce and they gain less weight. We know from studies done in the U.S., the honeybee colony collapse disorder reflects those same results regarding reproduction and general malaise. The Swedish study shows what is true for honeybees is also true for the other bee varieties which strengthens the case against pesticides even more, especially since there are more than 20,000 different species of bees in the world. In the past, the only studies done were on honeybees because an estimated 75 percent of “air traded” crops rely on honeybees for pollination.

These findings occur at a time when many farmers are increasingly switching from spraying fields to seeds that are already impregnated with neonicotinoids, so any insect which sucks or chews on the plant is poisoned while eating. Not only is the pesticide harmful to the pollinators, but to the pest controlling insects as well.

The manufacturers of pesticides, however, continue to say “if used properly,” their pesticides are safe for bees and other pollinators. They also dismiss scientific studies, saying that poisoning risks in the “real world” are smaller.

On this issue, our EPA (Environment Protection Agency) has not been as aggressive in its regulations against pesticide producing manufacturers as has been the European Union. But this past April, it did warn pesticide makers it was unlikely to approve new uses for the neonicotinoid class of pesticides. That ruling (which has raised the hackles of manufacturers) may have come about because of the national Pollinator Health Task Force established last year by President Obama, and/or because in March of this year, opponents of neonicotinoid use presented more than 4 million signatures to the White House calling for stronger action to protect pollinators.

Ursula Carlson, Ph.D., is professor emerita at Western Nevada College and credits David Jolly and Michael Wines of the New York Times (April 9 and 23, 2015) for the factual data in this column.