From the Amazonian rainforest to the mountains of Switzerland, bees are blending poison into their sweet honey.
Neonicotinoids, the neurotoxins common in pesticides, tainted around three-quarters of approximately 200 honey samples from around the world, researchers reported today in the journal Science.
“I purchased honey from an Indian chief when I was visiting central Brazil,” said Edward Mitchell, a biologist at the University of Neuchâtel in Switzerland. “I thought, ‘I’m buying this from an Indian. It will be pure honey.’ Guess what? It has pesticides.”
The findings don’t necessarily reveal the primary cause of colony collapse disorder — when worker bees leave their hive empty and don’t return — but they provide insight into yet another environmental factor that is putting stress on the pollinators that are crucial to the food chain.
“I’m happy to accept is multifactorial,” said Mitchell, referring to theories that colony collapse has many causes. “But if there is one factor we don’t need, it’s this one.”
Thirty percent of the honey sampled had one kind of neonicotinoids of the five commonly used in agriculture and gardening that Mitchell and his colleagues tested: acetamiprid, clothianidin, imidacloprid, thiacloprid, and thiamethoxam. Forty-five percent contained two or more. Ten percent contained four or five kinds of pesticides.
And 34 percent of the honey samples had concentrations known to be harmful to bees, including lowering reproduction rates and disorienting the critters so they can’t find their way back to their hives after they’ve found nectar.