Lu replicated commercial beekeeping procedures by feeding bees high-fructose corn syrup, an enzymatically treated super-sweet sugar used to give bees an energy boost. He spiked some of the syrup with imidacloprid. Many of the bees that fed on the neonicotinoid-tainted syrup left their hives in the middle of winter, a deadly mistake associated with colony collapse disorder.
"I believe one reason that commercial beekeepers are experiencing the most severe colony collapse disorder is because of the link between high-fructose corn syrup and neonicotinoids," Lu said in Wired.
But Bayer, a German chemical manufacturer that produces neonicotinoids, believes Lu used pesticide concentrations above what would be found in the field. The company states that imidacloprid residues have never been found in high-fructose corn syrup. They also contend that the imidacloprid Lu used has largely been replaced by another type of neonicotinoids.
BRIEF: Beekeepers Battle 'Perfect Storm'
Charles Benbrook of The Organic Center, an organic food research consultancy, told Wired that Lu would have gotten the same results regardless of the type of neonicotinoid the bees ate. Lu's study will be published in the Bulletin of Insectology in June.