In a recent story about agricultural chemicals used as seed treatments, I learned a bit about the possible connection between neonicotinoid insecticides and colony collapse disorder in honey bees. The biggest seller in the neonicotinoid category is clothianidin, made by Bayer CropScience and marketed as Poncho among other names.
This story has been active for years starting in Europe, and more recently in the U.S. Currently, scientists believe that CCD may have a number of causes, including the variola mite and viruses spread from Asian bee varieties. Some researchers think pesticide burdens may add to stress on bees
A recent EPA memo that was leaked to a Colorado beekeeper and sent to the media (I received the memo from the Pesticide Action Network of North America) suggests that in the U.S., clothianidin was given approval for use on corn crops without strong scientific evidence that bees would not be harmed.
The 99-page memo, dated November 2 from the Environmental Fate and Effects Division, raises concerns of EPA scientists about bee health and says that the Bayer study, done in Canada on fields of canola, was not sufficient to justify the product’s registration for use on corn in the U.S. The re-examination of the study, submitted in 2007, was spurred by Bayer’s request to register clothianidin for use on cotton and mustard seed crops.
Over at Grist, ag reporter Tom Philpott has written a detailed story with a time line that shows how EPA has handled the registration of clothianidin in the U.S.
According to Bayer, Clothianidin can be safely used as a seed treatment on canola, cereal, corn, sunflower, and sugar beet seeds to protect them against a host of early-season pests, as well as soil and leaf pests such as aphids, beet leaf miners, black cutworms, corn rootworms, grubs, and wireworms.
In Europe clothiandin, along with other neonicotinoids, has been long suspected by beekeepers of contributing to honey bee deaths by creating behavioral changes in the social insects that lead to a collapse of the hives. But a strong link has not been proven. In Germany, officials reported an incident of improper application of the product to seeds which allowed the chemical to drift in large amounts and caused problems for bee keepers. But when used as intended, Bayer says that clothiandin is safe for bees. The company has posted a great deal of information and research on its website.
Leave a Reply