Researchers in Ireland conducted an experiment to determine whether the herbicide glyphosate contaminates the nectar and pollen of crops and wild plants. To achieve this they surveyed seven fields of oil-seed rape crops and the blackberry/bramble growing in the surrounding hedgerows.
A glyphosate-based product was applied to the crop, and pollen and nectar were extracted from the oil-seed rape and blackberry flowers at various intervals. Pollen loads were also collected from honeybees and bumblebees foraging on the crop. The glyphosate and aminomethylphosphonic acid (AMPA) residues were determined using a liquid chromatography tandem mass spectrometry (LC-MS/MS) method.
Glyphosate was only detected in the blackberry nectar and pollen within one week of the application on the crop as a desiccant (used to dry the crop before harvest). Glyphosate was not detected in the nectar or pollen of the oil-seed rape when used as a pre- or post-emergence spray, or in the blackberry sampled at other times. The metabolite AMPA was not detected in any samples.
Other researchers have also found residues of compounds used as crop desiccants in wild plants, the environment and even honeybee matrices like honey and comb pollen, highlighting the risk of non-target exposure.
Application timing of the glyphosate product in the seven fields and the respective detections in the collected samples.
Copyright: Authors: Elena Zioga,Blánaid White & Jane C. Stout. Publication: Heliyon. Publisher: Elsevier. Date: December 2022.
Licensed under CC BY 4.0 https://creativecommons.org/licenses/by/4.0/
Read the full paper:
Zioga, E., White, B. & Stout, J.C. (2022) Glyphosate used as desiccant contaminates plant pollen and nectar of non-target plant species. Heliyon.https://www.sciencedirect.com/science/article/pii/S2405844022034673
Honey bee (Apis mellifera) on oilseed rape flowers.
Copyright: Gilles San Martin. Licensed under CC BY-SA 2.0 https://creativecommons.org/licenses/by-sa/2.0/