03
Nov
Bee Die-Offs Linked to Pesticide Mixtures, Window of Exposure
(Beyond Pesticides, November 3, 2009) Research by scientists at the University of Florida (UF) links Colony Collapse Disorder (CCD), the widespread disappearance of honey bees that has killed off more than a third of commercial honey bees in the U.S., to larval exposure to a cocktail of frequently used pesticides. Led by UF Institute of Food and Agricultural Sciences bee specialist Jamie Ellis, PhD, the researchers have finished a first round of testing on bee larvae exposed to the pesticides most commonly found in bee hives. The results were presented on October 22 at a meeting of the North American Pollinator Protection Campaign (NAPPC), which funded the study.
The work gives insight into how the larvae react to these pesticides, which are usually only tested on adult bees, and sets the stage for the researchers to test the bees’ reaction to combinations of these pesticides. Just like mixing the wrong medications can have deadly and unpredictable results in humans, chemical mixtures pose a quandary for the bee industry. Bees are commonly exposed to multiple pesticides that are either applied to or nearby their hives.
“Beeswax, honey and pollen can contain low mixtures of fungicides, insecticides, and herbicides. The larvae develop in the presence of and consume these mixtures,” Dr. Ellis said. “Any one of these pesticides may not be that harmful to the developing larvae. However, it is possible that combinations of the pesticides can interact.”
The work is among the first to look at such combinations of chemicals introduced at the larval stage. The study examines the individual effects of herbicides, fungicides and insecticides commonly found in bee hives (chlorothalonil, mycobutanil, simazine, glyphosate, chlorpyrifos, coumaphos, fluvanlinate, imidacloprid and amitraz). To study these pesticides, the researchers transferred individual larvae to special containers where they were given a typical diet containing a dose of the pesticide.
Some of the pesticides yielded surprising results. For example, the bees seemed to show an erratic response to coumaphos and fluvalinate, which are commonly used to kill hive-infecting Varroa mites. This could mean that some bees have become resistant to the pesticide while others have not, said Mike Scharf, PhD, a UF entomologist and co-primary investigator on the project.
“There’s a really complex and unpredictable interaction of chemicals and genetics at play,” Dr. Scharf said. Even more so, he added, when the bees are exposed at the larval stage. Pesticide exposure at this developmental stage could have significant effects on the adult bees.
Later research will reintroduce these adult bees into the hive to see how the pesticide-exposed bees react to common stressors, such as Varroa mites and bacterial infections.
“It is going to be a lot of work to run through all these scenarios, but at the end of the day, it’s the only way to really find out how all these factors come together,” Dr. Ellis said. “It’s worth the work. Bees are a fundamental part of our ecosystem and our food chain.”
Dr. Ellis says the research will be submitted for publication by the end of the year.
Research is ongoing as to the cause of the CCD phenomenon, but pesticides, especially neonictinoids, such as imidacloprid, have been implicated. CCD can be especially devastating since honeybees are essential pollinators of crops that constitute over one third of the U.S. food supply or $15 billion worth of food. For more information on pollinators and CCD, read our factsheet: Pollinators and Pesticides: Escalating crisis demands action.
Beyond Pesticides believes that pesticides are likely to be a part of the CCD equation and a precautionary approach must be taken. Solutions to the loss of bees and human productivity are clearly within our reach if we engage our communities and governmental bodies. We know how to live in harmony with the ecosystem through the adoption of sustainable practices that simply do not allow toxic pesticide use. Because our survival depends on healthy pollinators, we must do everything in our power to solve this problem.
Read other Daily News Blog postings on pollinators and pesticides.
Take Action: Email EPA Administrator Lisa Jackson and tell EPA to take a precautionary approach regarding pesticides that kill or have sublethal impacts on bees and other pollinators.
The key in this article that most people will miss is that coumaphos, fluvanlinate, and amitraz are all BEEKEEPER applied chemicals.
Thats right folks!
I have not seen this study yet but Maryann Fraziers work at Penn State showed these materials were the 2 or 3 most common chemicals in beehives in overall quantity by weight.
Meanwhile beekeepers blame Bayer and anyone else for their ills. Kind of hypocritical eh?
November 4th, 2009 at 12:02 amWhat about neonicotinoids and genetic insecticides being transferred to non-food plants that bees also pollinate? Could bees be killed by these plants?
November 21st, 2009 at 12:18 amThere is no such thing as a genetic insecticide that I am aware of so I’m not sure what your point is…..
As far as neonicotinoids are concerned they are used on crops like pumpkins, oranges and rapeseed. So unless border plants are oversprayed there is no way those materials are going to spread miles away to nonfood plants.
There is a lot of peer reviewed published data that shows the typical level of neonicotinoids that bees encounter on treated crops are far below levels proven to be harmful to honeybees.
Thats why there is such a controversy. A small and less educated group of beekeepers keep insisting that neonicotinoids are the source of their problems but there is no data even in new studies to back that claim up.
These same vocal beekeepers are mostly made up of huge industrial feedlot beekeepers who move their bees around a lot and also use a lot of miticides. Its a very hypocritical situation in my view. What’s even more bizarre is guess who makes a legal miticide that is proven to be poisonous to honey bees but beekeepers use it anyhow? Its called checkmite and contains the active ingredient coumaphos. BAYER!!!!
DOn’t beleive me? do a search on coumaphos and honey bees. Also the scientist author L. Burley as a keyword with coumaphos and honeybees to find the damning study that DOES show sublethal and lethal affects to honeybees from long term exposure.
So these beekeepers use a nasty organophosphate insecticide in their hives made by Bayer and then turn around and claim Bayer is killing their bees via neonicotinoid. What a joke!
November 24th, 2009 at 12:07 am