Quantification of imidacloprid uptake in maize crops

J Agric Food Chem. 2005 Jun 29;53(13):5336-41. doi: 10.1021/jf0479362.

Abstract

The systemic imidacloprid is one of the most used insecticides in the world for field and horticultural crops. This neurotoxicant is often used as seed-dressing, especially for maize, sunflower, and rape. Using a LC/MS/MS technique (LOQ = 1 microg/kg and LOD = 0.1 microg/kg), the presence of imidacloprid has been measured in maize from field samples at the time of pollen shed, from less than 0.1 microg/kg up to 33.6 microg/kg. Numerous random samples were collected throughout France from 2000 to 2003. The average levels of imidacloprid measured are 4.1 microg/kg in stems and leaves, 6.6 microg/kg in male flowers (panicles), and 2.1 microg/kg in pollen. These values are similar to those found previously in sunflower and rape. These results permit evaluation of the risk to honeybees by using the PEC/PNEC ratios (probable exposition concentrations/predicted no effect concentration). PEC/PNEC risk ratios were determined and ranged between 500 and 600 for honeybees foraging on maize treated with imidacloprid by seed dressing. Such a high risk factor can be related to one of the main causes of honeybee colony losses.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Flowers / chemistry
  • Imidazoles / metabolism*
  • Insecticides / metabolism*
  • Neonicotinoids
  • Nitro Compounds
  • Plant Leaves / chemistry
  • Plant Stems / chemistry
  • Pollen / chemistry
  • Zea mays / chemistry
  • Zea mays / metabolism*

Substances

  • Imidazoles
  • Insecticides
  • Neonicotinoids
  • Nitro Compounds
  • imidacloprid