Clothianidin is an insecticide belonging to a relatively new class of pesticides known as neonicotinoids. These nicotine-based chemicals are systemic in action, meaning that they are taken up through a plant to poison all of its parts. They are of great concern to beekeepers around the world because they poison the nectar and pollen consumed by honey bees and other pollinators. Clothianidin is often coated onto the seed of crops. It is in widespread use in the United States as an insecticide on corn, the nation’s largest crop. Other crops treated with clothianidin include canola, soybeans, sugar beets, sunflowers, and wheat. While corn, a grass, provides no nectar, it does produce a large amount of pollen, which is very attractive to honey bees. The use of clothianidin has steadily increased since its conditional registration in 2003. Beekeepers have experienced heavy winter die-offs from that time to the present.
The EPA quietly presented Bayer with full registration of clothianidin in April of this year following a seriously flawed trial funded by Bayer. The trial, conducted in Canada, placed hives near canola plots treated with clothianidin and untreated control plots. Remarkably, both plots were located so close together that the honey bees had free access to both. EPA scientists questioned the validity of the trial. Others experts analyzing the trial found significant flaws in its design: corn produces much more pollen than does canola; corn pollen is more attractive to honey bees; and canola is a minor crop in the US, while corn is the most widely planted crop. The neonicotinoids, including imidacloprid, are suspected by beekeepers and many scientists as contributing to honey bee colony collapse disorder. Clothianidin is a persistent pesticide, meaning that it remains in the environment for a long time, and the pesticide is highly toxic to honey bees. You may read the report at http://www.grist.org/article/food-2010-12-10-leaked-documents-show-epa-allowed-bee-toxic-pesticide-. Without independent investigation, the neonicotinoids remain suspects in colony collapse disorder. Clothianidin is banned in Germany, France, Italy, and Slovenia. Today’s photo: clothianidin-treated corn.--Richard