Study: no evidence for Syngenta’s pesticide collapses bee colonies

A newly released study from Britain’s Food and Environment Agency with the University of Exeter shoots down the claim that Syngenta’s neonicotinoid pesticide is the cause of Colony Collapse Disorder among the world’s honeybee populations. The new study admitted that pesticides can be harmful to individual bees, but it is unlikely to cause whole colonies to collapse.

"We do not yet have definitive evidence of the impact of these insecticides on honeybees and we should not be making any decisions on changes to policy on their use,” said James Cresswell, the exotoxicologist of the British study.

France banned the use of the pesticide, Cruiser OSR, earlier this spring after French scientist Mikael Henry published an article showing the death rate of bees increased when they were fed nectar laced with thiamethoxam, the active ingredient in Cruiser OSR.

Britain’s study criticized Henry’s research because it questioned if the first used an inappropriately low birth rate and underestimated the rate at which colonies can recover from the loss of bees.

"They modeled a colony that isn’t increasing in size and what we know is that in springtime when oilseed rape is blossoming, they increase rapidly,” Cresswell told Reuters.

Another critique of the French study included the way bees were given the nectar laced with the insecticide. The dosage given was equivalent to a full day’s intake. For humans, that would translate into drinking eight cups of coffee at once rather than across a full day, Cresswell explained.

"We know that neonicotinoids affect honeybees, but there is no evidence that they could cause colony collapse,” Cresswell told Reuters. “When we repeated the previous calculation with a realistic birth rate, the risk of colony collapse under pesticide exposure disappeared.”