Neo-nicotinoid insecticides are used to treast corn, sunflower and rape seeds offering protection against many pests. Their use has been implicated in the widespread problem honeybee colony collapse, which is threatening the survival of a major crop pollinator species.

A study using Ultra High Performance Liquid Chromatography reveals that physiological fluids of corn plants can effectively transfer these insecticides from the seed on to the leaf surface. These contaminated droplets of fluid then expose honeybees drinking the fluid to potentially toxic concentrations of the insecticides.

• Rapid analysis of neonicotinoid insecticides in guttation drops of cornseedlings obtained from coated seeds,
  Andrea Tapparo, Chiara Giorio, Matteo Marzaro, Daniele Marton, Lidia Soldà and Vincenzo Girolami,
  J. Environ. Monitor. 2011.
  DOI: 10.1039/C1EM10085H