A microgram is 1 millionth the size of a gram. A milligram is 1 thousandth the size of a gram. Rounding 8 micrograms to a milligram seems like a stretch to meQuote:
Originally Posted by WLC
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A microgram is 1 millionth the size of a gram. A milligram is 1 thousandth the size of a gram. Rounding 8 micrograms to a milligram seems like a stretch to meQuote:
Originally Posted by WLC
When comparing the weight of a bee to a 150 lb person, micrograms are real numbers.Quote:
Originally Posted by Solomon Parker
The biggest reduction in contaminants is, of course, to not dump chemicals in your hives. The best approach to minimizing contaminants, on the other hand, is to not put anything in your hives that may contain toxins that could affect the bees.
In addition, toxicity to humans for a variety of chemicals is in the microgram range.
The LD50 of many of these wax contaminants is 2ng/bee.
I am comfortable going from ng/g to ppb, etc. . The 1st paper showed amounts in the ppm range for individual contaminants.
What we need to know is how much wax (in grams) is used to coat a plastic frame (or contained in a sheet of foundation) to get an idea of how close to the LD50 you get.
I think it's pretty close per frame. I would also note that synergistic effects have been shown to occur when different pesticides are combined.
The second paper showed lower pesticide amounts and had some useful median values as well.
I suppose someone could take out a calculator once all the values are known to see how bad things can get when using wax foundation or coated plastic.
It's a useful way to compare the pesticide burden in wax foundation/wax coated plastic frames vs foundationless.
Why guess?
From the emotion being posted on this topic, I get the idea that there are a lot of people watching this thread that are losing sleep over this. To their horror they've realized that they are using plastic frames in their hives and that they have given their bees a death sentence from vast (i.e. microgram) amounts of toxic sludge found in the wax coating of their frames.
Just want to offer a sanity check here. We are talking about the thin layer of wax coating on the frames and it's level of contamination was at a concentration that was habitable to previous hives. That coating wax is minuscule compared to the actual clean wax that they will draw out on the frames over top of this and use.
How much wax is used to coat a set of 10 frames? Is it even a grams worth used to coat a full set? The actual amounts of wax that gets harvested by melting down completely drawn out frames is nothing (and thats for full drawn out comb not the wax coating).
are you suggesting that individual bees are ingesting micrograms of the toxins? I wouldn't necessarily think that the 60,000 bees concurrently living in the hive (or even a year's worth of subsequent bee generations) would be collectively consuming micrograms of toxins.Quote:
Originally Posted by SantaFeBeek
Based on what WLC said above, that the LD50, which means that 50% of the bees will die at that concentration, is 2 nanograms per bee. That means one bee would only need 2 or 3 1000ths of a microgram to die. I don't doubt that there are various detrimental effects to the bees systems at lower dosages than that.
Another problem that I can see with wax contaminant accumulation is that as foundation is used and more contaminants are collected in that wax, then the wax is recycled for more foundation, the contaminant concentrations would logically be getting higher and higher over time. That would be an interesting study, as well.
Good discussion! I hadn't thought about a lot of these issues this critically before.
There's alot of information in both papers. They're worth looking over at least a few times.
However, I don't think that a gram or 2 of wax per plastic frame is an exageration. Also, wax foundation probably comes in at alot more than a gram per sheet.
I'd say that a sheet of wax foundation can easily have 10-100 ug of pesticides.
PS-Don't forget that the fungicides can interfere with pollen/nutrition, etc. .
Here is another thought. As a beginner would you rather be choose a method that involves picking out the right kind of foundation among dozens of choices, choosing the right size, wire or no wire, maybe getting an extractor, monitoring for diseases and then choosing a chemical treatment that may or may not work and then determining the right time to use it,
Or,
Being told just to buy all medium boxes and medium frames, coming up with a guide and then just dumping the bee's in there and basically ignoring all the the terrible things that you hear about effecting hives until fall where you simply pull out your frames, cut out the comb and strain the honey in a plastic bucket. If your hives die then your not a failure, your just removing bad genetics.
Even assuming none of this is actually true, which method sounds the most appealing?
Its the same reason people by Apple (computer) products. Simplicity is perhaps the most appealing trait that a product can have.
O-oo, I am sorry. Try this:Quote:
Originally Posted by rweakley
http://www.plosone.org/article/info%...l.pone.0014720
it is the same as WLC's a few posts above. It would be really great if you could evaluate it. To me it sounds OK and experimental part is fine with me, but I am not experienced in beekeeping, so I could not tell if any flaw in bees part of the experiment.
I have two beehives in urban environment for 10 month. These bees are survivors. They never saw any "treatment" on purpose. They were the same way for 2 more years before I inherit them. They used to have some occasional frame with foundation. Now they are 95% foundation free. One hive recently swarmed (my mistake) and small (one deep) in comparison to another - nest occupies 3 mediums and 3 more medium full of honey on top, total 6 mediums. This gigantic one has a stable mites count of 50, which I guess considered to be high, but bees are living with this for 10 month with me and 2 years before. There is no evidence of complication from mites. I never was introduced to her Majesty, but it looks like they are flourishing. I never did a deep inspection of the nest and could not tell to you how much, for instance, pollen they have... In Los Angeles we have quite a big movement towards a natural beekeeping. I do not think that "natural" is the same as "treatment-free". The idea of letting bees die by "natural cause" seems to me ridiculous - we bring them from Europe by force, placed them in unnatural conditions and now, like God, imposing the "unnatural selection" on them ... I would help my bees to survive if I could - same way as I would help any animal, who is in trouble. The problem is that as with any wild animal, how to know what is good for them? Do not do more damage. This is a real challenge. With bees - they teach me what is good and what is bad for them. I am a good learner so far. I wish you bees be happy and healthy! SergeyQuote:
Originally Posted by WLC
Is the LD50 rating based on bees ingesting the 2 nanograms of toxin, vapor exposure to the toxin, or is it based on skin contact? I'm assuming the rating is based on ingesting it in a water-based food solution which is much different measurement than exposure of it residing in buried wax.Quote:
Originally Posted by SantaFeBeek
Again if the LD50 was based on a bees exposure to the toxin in wax, it would have killed off the original hive that had its entire comb containing the concentrated toxins well before it reached that level.
Table 4 in the second paper is a good place to look at the range of various pesticides found in wax relative to their LD50s.
There is an average of 12.4 ug of various pesticides per gram of wax.
As for how all of these various pesticides can impact a hive...
It's not just in the wax.
Googling I found that some beekeepers who roll their own wax on waxless frames use roughly 2 pounds for 100 frames. If you go with that as a baseline that converts to about .3 grams of wax to coat the 2 sides of a frame. I would speculate that the frame companies are even more efficient when applying wax, so the standard store bought frames would likely use less than .3 grams.Quote:
Originally Posted by WLC
If i can extract my deeps and mediums I'm sure you will be able to move your hives without too much trouble.Quote:
Originally Posted by BeeGhost
The only thing missing was the exact methodology of how they extracted the pesticides and such from the wax, what kind of standard material did they use, did they use an internal standard (another chemical that is put in with the standard sample and the sample being tested, helps remove equipment noise and such.) I will assume from the overall professionalism of the rest of the paper that the other methodology was probably correct as well. Sounds like they were using better equipment than I used when I was in a lab. My machines were almost as old as me. I didn't read the whole thing yet, just enough to get the jist of things.Quote:
Originally Posted by cerezha
Did anybody take arithmetic in the middle school? 1 pound is approximately 450 grams times 2 = 900 grams divided by 100 = 9, nine! grams of wax per frame!!!! Is this number manipulation done purposely? To confuse people? SergeyQuote:
Originally Posted by BayHighlandBees
SantaFe,Quote:
Originally Posted by SantaFeBeek
I think for concentrations to get higher and higher from recycling wax it would require a much thicker amount to be applied to new plastic foundation than is. If you are only applying enough to coat the plastic, I don't see how that would ever move the dial on increasing the concentrations. Perhaps wax foundations might have more possibility of a cyclical effect?
Many thanks Rod. Since they sent samples to specialized laboratory for analysis, I guess, they used a standard to the field procedures. It is common practice in research papers to refer to the standard procedure instead describing in details. SergeyQuote:
Originally Posted by rweakley
my bad, I converted to Ounces :pinch:
Quote:
Originally Posted by cerezha