
Honeybee deaths linked to seed insecticide exposure - llambda
http://www.physorg.com/news/2012-01-honeybee-deaths-linked-seed-insecticide.html
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ars
Maybe it's a poorly written summary, but I see no link.

I see findings of insecticide, and I see bee deaths, but I see no finding of a
link - I don't even see a correlation.

To show a correlation you have to compare rates of bee deaths in various
locations, and rates of insecticide use. Then establish they move together.

Even that is not a link, but it's something. To actually establish a link you
have to manipulate insecticide usage and watch bee deaths change.

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keithflower
A "link" and "correlation" is already well-established[1][2][3][4], and the
toxicity of clothianidin in honeybees is not the issue here. The LD50 for the
substance and many other chemicals is very well-known for honeybees.

The paper investigates _routes of exposure_.

Reading the actual paper may help:

[http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjourna...](http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0029268)?

"In terms of acute toxicity (based on the oral LD50 of 2.8 ng/bee [23]), the
amount of clothianidin on a single maize seed at the rate of 0.5 mg/kernel
contains enough active ingredient to kill over 80,000 honey bees. However, the
overall level of risk has been more difficult to quantify, as there has not
been a clear mechanism whereby honey bees could be exposed to high levels of
these compounds – once the treated seed is planted, opportunities for honey
bee exposure to concentrations of neonicotinoids over a wide area should drop
dramatically (although see [19]). Our results suggest that of the factors we
quantified in this study, used talc exhausted during and after planting (the
latter would occur during routine cleaning of planting equipment) stands out
as potential routes for exposure that should be prioritized for further
quantification and remediation."

"Detection of clothianidin in pollen, both in stored pollen in cells and in
pollen traps is a critical finding because clothianidin is even more toxic
when administered to bees orally, with an LD50 of 2.8–3.7 ng/bee. Given an
average weight of 80–100 mg/bee, some of our pollen sample concentrations
exceed the oral LD50. This, combined with the result that our samples of dead
and dying honey bees consistently demonstrated the presence of clothianidin,
suggests that the levels of both clothianidin and thiamethoxam found in our
sampling of stored pollen in May of 2011 may have contributed to the deaths of
the bees we analyzed. However, our analytical methods do not allow us to
determine what fraction of the pesticide is on the surface of bees (contact
toxicity, due to drift of soil or planter exhaust) vs. inside the body (oral
toxicity, due to ingestion of contaminated pollen or guttation droplets). A
combination of these exposure modalities is not unlikely.

[1] US Environmental Protection Agency, Office of Pesticide Programs.
Factsheet Clothianidin (2003) EPA Publication 7501C;
www.epa.gov/opprd001/factsheets/clothian​idin.pdf.

[2] National Agriculture Statistics Service (NASS), online database: Crop
production 2010 summary (2010) Available:
[http://usda.mannlib.cornell.edu/MannUsda​/viewDocumentInfo.d...](http://usda.mannlib.cornell.edu/MannUsda​/viewDocumentInfo.do?documentID=10471).
Accessed 2011 July 10.

[3] Laurino D, Porporato M, Patetta A, Manino A (2011) Toxicity of
neonicotinoid insecticides to honey bees: laboratory tests. Bull Insectol 64:
107–113. FIND THIS ARTICLE ONLINE

[4] US Environmental Protection Agency, Office of Chemical Safety and
Pollution Prevention (2011) PC Code: 044309. Memorandum: Clothianidin
registration of Prosper T400 seed treatment on mustard seed and Poncho/Votivo
seed treatment on cotton. (2010). Available:
www.epa.gov/pesticides/chem_search/clear​ed_reviews/csr_PC-044309_2-Nov-10_b.pdf
Accessed 2011 Aug 1.

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tantalor
Do they expect me to believe that insecticides might be killing insects?

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mxavier
There's a 2009 Documentary called Vanishing of the Bees that covers this. It
was quite alarming to see the impact it had on beekeepers in the US. If you
have netflix, the doc is available for streaming and is well worth the watch.

~~~
rdtsc
I watched "Colony" also on Netflix which related the problem as well. But
dramatized a bit too much by focusing on this one family.

Regardless, it was interesting to see how beekeepers were basically positioned
against the legal team and the lobbyists of the chemical companies. The
position of the chemical companies was basically to answer the problem with a
question "Why would we knowingly damage agriculture in this country, we want
agriculture to do well long term as well, right?". A very clever PR trick.
They also said they conducted their experiments but found no positive results
that links honeybee deaths to their insecticides (big surprise there).

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anamax
There have been lots of explanations for honeybee deaths.

Here's another recent one - [http://news.yahoo.com/blogs/sideshow/parasite-
turns-honey-be...](http://news.yahoo.com/blogs/sideshow/parasite-turns-honey-
bees-zombies-212258832.html) .

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jsundquist
If this is true, then what about the honey they produce? Wouldn't the honey
have high levels of these toxic substances? Then in turn consumers would be
getting a heavy dose of these chemicals. Scary stuff.

