A new study published in the Nature journal shows that neonicotinoids, a widely used pesticide, have an addictive effect on honeybees and bumblebees. When given the option of either a sugar solution laced with two kinds of neonicotinoid pesticides or plain sugar solutions, bees chose the pesticide solution even though they were more likely to die.
A related study published in the same journal also showed that bees foraging in neonicotinoid-treated crops were less likely to reproduce and gained less weight than their counterparts in untreated fields.
One hypothesis, from lead researcher Geraldine Wright, is that the chemicals affect reward centers in the bees’ brains in the same way that humans are affected by cigarettes.
“Like nicotine, they are essentially amplifying the rewarding properties of the sucrose solution that they are located in,” Wright told The Guardian. “The bees think it’s more rewarding so they go back to that food tube to drink more of it.”
In the United States, where the majority of corn and soybean crops are grown from seeds treated with the pesticide, its use has been rife with controversy.
Manufacturers maintain that the pesticides are safe for bees and other pollinators, dismissing evidence to the contrary. Meanwhile, the Environmental Protection Agency said this month that it “will likely not be in a position to approve most applications for new uses of these chemicals.”