New study offers more clues on neonicotinoids and bees
When it comes to bees, not all pesticides are equally toxic, federal scientists said after studying 42 common pesticides in a field trial.
With honeybee populations declining at an alarming rate, the new findings may give farmers and regulators some tools to guide pesticide applications.
The researchers found that 26 pesticides, including many (but not all) neonicotinoids, organophosphates, and pyrethroids killed nearly all of the bees that came into contact with the test pesticide sprays.
But seven pesticides, including glyphosate and acetamiprid, killed practically no bees in the tests. Glyphosate is the active ingredient in the herbicide commonly known as Roundup and acetamiprid is a neonicotinoid.
The tests, designed to simulate in-the-field conditions, yielded a few surprises. Sulfoxaflor, a pesticide recently approved by the EPA in a decision then overturned by a federal court, was found to be near the middle in terms of toxicity. The study found sulfoxaflor was less toxic to bees than permethrin, a pyrethroid insecticide that is used in agriculture, household pesticide products, flea shampoos for pets, and in head lice products for people.
“Our data, particularly the ratios of field application rates to lethal concentrations of each pesticide, provide a quantifying scale to help extension specialists and farmers with pesticide selection to maintain effective control of target pests and minimize the risk to foraging honey bees as well,” the authors wrote. The findings are published in the Journal of Economic Entomology.