I got a PhD in chem. Fischer got a PhD in physics. We probably have an MD bee keeper on the list. And a lawyer. I will practice chemistry where I am educated and refrain from practicing physics, medicine and law.
Odors are very specific to the chemical structure. For instance alpha and beta napthyl amine smell somewhat alike but not identical. There is no language in the world that has decent words for odors simply because there are so many different odors you would need tens of thousands of words and still not have a good description. We all produce one product which we call honey. Yet the odors of those honeys vary widely. We still call all of them honey.
The reason to use butyric anhydride to remove bees from supers instead of butyric acid is obvious to a chemist. It only takes a very small amount of butyric acid to do the job. And temperatures vary wildly under use conditions. If you tried to use butyric acid a common result would be a bee kill like Randy saw. And an equally probable result would be far too many bees left in the supers. The reason is it would be hard to judge how much butyric acid to use. On a cool, cloudy day you would need a lot more than on a hot sunny day. The reason is butyric acid is fairly volitile and as a result its vapor pressure changes rapidly with fairly small changes in temperatures. From a chemists standpoint the obvious way to control the concentration of butyric acid the bees are exposed to is to use some type of controlled release scheme. One controlled release scheme that is less sensitive to ambient temperatures would be to simply mist a controlled amount of butyric acid over the tops of the bars. Then you have to have a mister of some type that is inert to butyric acid and mechanically durable and that does not plug when you get a bit of dirt in it. Not impossible, but likely a constant pain in the posterior to get it to work right most of the time.
An easier way is to use some reasonably safe chemical of lower volatility than butyric acid that will react rapidly with water vapor in the air or water vapor in the bees air passages and release butyric acid when it reacts with that water. You can rule out the acid chloride or acid bromide of butyric acid as both are more volatile than butyric acid and also release hydrogen chloride or hydrogen bromide upon hydrolysis which are much more corrosive than butyric acid. The obvious choice is butyric anhydride. It is considerably less volatile than the free acid and as a result its vapor pressure will be far less sensitive to temperature changes under use conditions than that of butyric acid. Under hive conditions butyric anhydride produces no products other than butyric acid which is the active ingredient you are after. The only real effectiveness question is does the anhydride have enough volatility under use conditions to be effective? The experimental answer is obviously yes. The other question is a legal issue. Namely is it acceptable to FDA? Anyone who feels it should be banned is free to contact FDA and ask them to go after the manufacturers that produce the product for bee keepers and put them out of the business. With such a request FDA is going to make a judgement if there is a food safety issue and if the judgement is no they are going to do nothing. My guess is they would do nothing. Or they might just give it a restricted use on the GRAS list.
I would expect any chemist who had any significant experience to conclude butyric anhydride would be a good butric acid source to test and determine effectiveness in removing bees from a super given that butric acid and other short chain aliphatic acids were known to do this job. I have had people report to me that had a BS or MS in physics and based on that small sample I would not expect a physicist to know enough basic chemistry to get thru that logic process. I would also not expect an MD or lawyer to know that basic chemistry either. That is why companies hire more than one technical expert to work on their projects. Companies need a variety of skills, not just one skill.
This has gotten way too far from the purpose of this list which is bees. Bee keepers do not need to be chemists. So, I will refrain from further comment on this topic.
Dick
" Any discovery made by the human mind can be explained in its essentials to the curious learner." Professor Benjamin Schumacher talking about teaching quantum mechanics to non scientists. "For every complex problem there is a solution which is simple, neat and wrong." H. L. Mencken
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On Thu, 8/4/16, James Fischer <[log in to unmask]> wrote:
Subject: Re: [BEE-L] Bee kill from fume boards?
To: [log in to unmask]
Date: Thursday, August 4, 2016, 10:59 PM
> Butyric anhydride does not react
at all with oxygen at room
> temperature and when it reacts with water there is no
> change in valence state.
Where is there a roomful of "room temperature" pure oxygen
containing with
no water vapor?
That would be a very scary room to be in, I'd be much more
afraid of a spark
than the Butyric anhydride.
I doubt that such a room would have any utility in
beekeeping.
> This [the odor] is simply an irrelevant red
herring.
On the contrary, the odor is the crux of the matter!
> The odor of butric anhydride is not expected
> to be the same as the odor of butric acid.
> They are two entirely different chemicals
> with each having its own odor.
But the admission that butyric anhydride has an odor at all
clearly
contradicts the prior flatly-made statement:
> "Butyric acid is not one of the byproducts,
> it is the only product of such hydrolysis."
The odor has to come from somewhere, and chemistry is not
magic, so if the
only reaction possible is hydrolysis, and the only product
or byproduct
produced is butyric acid, then:
1) How is there ANY odor other than the odor of butyric
acid?
2) Why is the butyric anhydride used, rather than the
butyric acid, if the
only product of hydrolysis is the acid?
3) Is some of the butyric anhydride NOT reacting with
the ubiquitous water
vapor in the atmosphere when exposed? Why?
4) How can one smell butyric anhydride in anything
other than a
moisture-free atmosphere?
An odor tends to start as a "volatile organic compound" and
VOCs tend to
have some carbons. They have to come from somewhere,
so if such flat
statements are going to be intoned as if they were
absolutes, someone has to
explain to us where all those odiferous VOC vapors come
from. The strong
odor (the only reason beekeepers even care about this
chemical) should be
explainable in terms of the reaction of the butyric
anhydride with the
ambient atmosphere, which certainly does always contain some
percentage of
water, some oxygen, some nitrogen, and so on.
One does not need to bogged down in the details of chemistry
to see that the
what is going on is more complex than described, as
otherwise, the only odor
would be that of butyric acid, and the anhydride would never
be used, as it
would provide no advantage in terms of being more
"odiferous" over butyric
acid, it would simply be "freeze-dried butyric acid - just
add water".
But 'splain it to us all - don't use "debating tactics" like
dismissing a
reasonable question as a "red herring", answer the
question.
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