August 31, 2016
Many stories have been published regarding the effects of neonicotinoid pesticides and how they negatively impact honeybees and other pollinators. So far have studies and stories gone that some companies and state governments are phasing out these pesticides and regulating how much they can be used, respectively. However, a recent study offers the counter claim that while neonic pesticides are harmful to bees in large doses and should be used with caution, they may not be as major a cause of the enigmatic colony collapse disorder (CCD) as many believed in the past.
Regarding the scrutiny and criticism neonicotinoids have faced due to their supposed effects of disrupting bees’ sense of direction, the new Washington State University study, published in the Journal of Economic Entomology, shows that the chemicals within the pesticides pose small risk to honeybees in real-world settings because the bees aren’t exposed to enough to cause much harm.
With the help of 92 WA beekeepers, the team of entomologists studied apiaries in urban, rural, and agricultural areas across the state. The team collected samples of stored pollen from 149 apiaries, and during their one-year trial, the researchers looked at potential honeybee exposure to neonicotinoids due to pollen foraging. According to the study, residues were detected in fewer than five percent of apiaries in rural and urban landscapes. Two common neonicotinoids—clothianidin and thiamethoxam—were found in roughly 50 percent of apiaries in agricultural areas, but the amounts were considerably less than what other studies have shown to not affect honeybee colonies.
“Based on residues we found in apiaries around Washington state, our results suggest no risk of harmful effects in rural and urban landscapes and arguably very low risks from exposure in agricultural landscapes,” said Allan Felsot, a professor of entomology and environmental toxicology who co-authored the study. Beekeepers around the state, like Matthew Shakespear who manages a honey business and 15,000 hives on the West Coast, have not been surprised by the study's results. “I don’t really feel like [neonicotinoids] are an issue,” Shakespear said. “I know there are other beekeepers who disagree with me on that point, and all I can say is for our operations, I have not seen [that neonicotinoids] are a problem.”
“I think sometimes the pesticides are blamed when it’s not exactly pesticides; it’s a management issue. The only way to fix that is to be honest about what’s going on,” Shakespear also said. However, pesticides do remain a concern. While exposure levels were small in the WSU study, lead author Timothy Lawrence said it’s still important to be careful when using neonicotinoids and to follow product label directions. “While we found that bees did not have chronic exposure to adverse concentrations of neonicotinoids, we are not saying they are not harmful to bees—they are. People need to be careful with pesticide use to avoid acute exposure.”