Stan
You ask good questions, regarding the chemicals used on corn, levels in
2006, and concentrations.
I don't have the dates for the period of years over which the switch from
imidacloprid to clothianidin and thiomethozam seed treatment was made in the
US, but as you point out, the question is for 2006 when the first big CCD
event was reported.
The 2007 USDA Data Summary for pesticides found for Corn Grain (Appendix F)
reports:
For 655 analyzed samples of corn grain, there were NO DETECTABLE
concentrations of either imidacloprid or clothianidin.
For 280 samples of corn grain analyzed for thiomethoxam, there were NO
DETECTABLE concentrations of thiomethozam.
So, hundreds of samples of corn were analyzed and NONE had detectable
levels of any of the three chemicals. If there was NO detectable chemical in
the corn meal, its not going to be at toxic levels in corn syrup, even if
you question whether these chemicals break down and would be filtered out
during the manufacturing process.
I've a minor in biochemistry as part of my Ph.D. I don't pretend to know
the HFCS manufacturing process well enough to thoroughly evaluate it based
on my own knowledge, but I know enough to talk with chemists who do, and
I've talked to several - they all made the case that the processing would
eliminate any chance of any of these chemicals making it through to the
final product. That and the fact that USDA monitors pesticides in corn grain,
is probably why your HFCS supplier is not analyzing from these chemicals.
However, if you are really concerned, simply send samples to a lab such as
the USDA Gastonia lab. Roger will be happy to analyze them for you,
assuming you are willing to pay for the analyses.
You also stated: <The fact that you and I consume corn is completely
irrelevant. The allowable residue of imidacloprid in tomato paste is 1,000 ppb
so it would be totally toxic to bees. >
I agree with the concept of your statement. One can't directly compare
toxicity levels in terms of dose to a small insect and to a large mammal, and
we do have very different bodies and nervous systems.
But, that wasn't my point. Because USDA is concerned about the quality of
the food that you and I consume, they analyze foods every year. These
reports are readily available on the web.
So, if Harvard had bothered to look, they would have found the results for
corn grain from 2006. NO, absolutely NO, detections of any of the three
neonicotinics used for seed treatment. Their entire premise of CCD being
caused by these chemicals in HFCS ends right there. Their premise is based
on a false argument.
Also, FYI, the EPA allowable residue levels for these three chemicals in
corn grain IS NOT 1,000 ppb.
It is 20 ppb for Thiomethoxam, 20 ppb for Clothianidin, and 50 ppb for
imidacloprid. So, the level of concern in terms of protecting human health
from these three chemicals is not the 1000 ppb that you and I could both
agree is likely to be 'totally toxic to bees'. The level of concern for
humans is close to the range to which the Harvard folks exposed bees.
Hopefully, your worries about HFCS should also be addressed by the USDA
results. From our own analyses, the chemical to worry about in HFCS is
Hydroxymethylfurfural (HMF). That chemical is toxic to bees and can appear at
toxic levels if something goes wrong in the manufacture, handling, or
storage of the syrup. Don't store in metal containers, don't expose to heat,
and don't add fresh syrup to old in your own tanks. Clean out old syrup
before adding new.
Jerry
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