Vapourising Oxalic Acid

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Thank you Hivemaker for your latest posts, one of which contains info that has been seen before, except for those who are biased care to not read and understand what is put in front of them. Frankly I doubt that the non believers in sublimation of oxalic will ever accept the posts you have provided or anybody else views where it doesn't coincide with their own biased outlook. I just wish they wouldn't embroider their views with scaremongering - as did the Chairman of my BKA last year when he said "there had been fatalities by oxalic sublimation of beekepers in Germany". I didn't have the nerve to correct him in public - after all he is a master beek - but I did copy him the links within your previous posts and elsewhere and asked for his evidence in support of his irrational comment. Silence naturally!!!
 
Results from the trials have not been officially published, but Prof Francis Ratnieks told the Telegraph that in the most effective format – a vapour at a particular concentration – the treatment was 97 to 98 per cent effective.


This is the LASI study that I was able to discuss with the researchers at the LASI open day last summer.
It is the study where they ensured, by brood culling, that there was nowhere for varroa to hide and escape treatment.
The results then showed a very small increase in efficiency (fractionally more varroa, and fewer bees, killed) compared to trickling.
Both were better than spraying Oxalic (like Lactic) - which I have never heard of anyone actually doing in this country.
Without the brood culling, the influence of any sealed brood would mask the small difference in treatment efficacy.

The researchers were insistent that respect for the danger of Oxalic vapour required the use of proper personal protective equipment.
They even had their gas mask on display on the table.

And they were extremely impressed by the pennies that could be saved on each hive, by the reduced consumable cost of crysals versus syrup. As they pointed out, with a few hundred hives, the cost of vaporising kit and PPE would be quickly recovered ...

In conversation they were in full agreement that the fractional benefits did not justify the outlay for the hobby beekeeper with a couple of hives.
However - and I do not disagree in the least - they felt that the speed (reduced man-hours) with the effectiveness fully justifies the use of the method for commercial operations with large numbers of hives.
And it should also be noted, the researchers' enthusiasm for trickling, as a method for the hobbyist, was such that they were demonstrating how to make up the solution. The actual researchers involved (as opposed to Ratniek's press release) were {ADDED quite happy with trickling.}

In summary, I agree with those LASI researchers that, using proper PPE, sublimation is an appropriate technique for large-scale or commercial beekeepers with isolated apiaries, and that it is utterly inappropriate for the hobbyist with a couple of hives in an urban setting.
There is a valid discussion to be had as to what the cross-over point might be.
My estimate would be that the crossover is somewhere around the 20 hive mark. Definitely not at 2 hives.
And that the technique is not appropriate for the beekeeping beginner.


Incidentally, the researchers thought that it might be a good idea for Associations to invest in the kit (and PPE), and lend/hire it to members.
When asked about the legal liabilities involved, they admitted it wasn't something they had considered.
 
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It is the study where they ensured, by brood culling, that there was nowhere for varroa to hide and escape treatment.
The results then showed a very small increase in efficiency (fractionally more varroa, and fewer bees, killed) compared to trickling.

Without the brood culling, the influence of any sealed brood would mask the small difference in treatment efficacy.

Of course, not much difference in either treatment if brood present, but the general idea in the winter treatment is that the bees are broodless, but if not, they can be treated two or three times 5 to 7 days apart, to cover this period using sublimation, not recommended using the trickle method because of the harm it does. Both carry on working for several days, but from observations the effective kill rate drops off rapidly in colonies with brood after around six days.
 

There are other quotations that are relevant from the paper linked.

The technical rule for hazardous substances „TRGS 900“ of German „Bundesministerium für Arbeit und Sozialordnung“ limits the concentration of oxalic acid in the air at working places to 1.0 mg/m3 [4].
Note that this is HALF the exposure limit that Randy Oliver (scientificbeekeeping.com) quotes.

And the researchers did NOT conclude that NO masks were required!
This is what they said
Therefore direct skin contact with oxalic acid solution has to be avoided by wearing water- and acidproof gloves. The direct, frontal impact of oxalic acid particles on the mucous membranes of the eyes must be prevented by wearing safety-goggles. In addition, the beekeeper must protect himself against irritation of the respiratory system through temporarily higher concentrations of oxalic acid in the air. Thus, it is advisable to wear a protective mask. The company Andermatt Biocontrol AG, manufacturer of the Varrox-evaporator, recommends a protective mask of the type „FFP3 SL“. This protects in accordance with the European standard „DIN EN 149“ against solid and liquid particles in concentrations up to 50 times the exposure-limit. The presented results prove however that a protective mask of the quality „FFP2 SL“ is completly sufficient since this protects against solid and liquid particles up to 10 times the exposure-limit and such high concentrations were never reached. The 20 participating beekeepers largely used the provided protective masks „FFP3 SL“. Others used their own protective masks of varying qualities.
None used no mask whatsoever.
 
Itma, can you provide any research papers/statistics on the numbers of beekeepers that have died, injured, directly as a result of treating their bees with oxalic acid sublimation...list of beekeepers names, in this country or others, actual facts.

Bit like the statistics that can be found on alcohol abuse, road deaths ect.
 
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Itma, can you provide any research papers/statistics on the numbers of beekeepers that have died, injured, directly as a result of treating their bees with oxalic acid sublimation...list of beekeepers names, in this country or others, actual facts.

Bit like the statistics that can be found on alcohol abuse, road deaths ect.

The trouble is that the impact of exposure to such inoccuous airborne chemicals is not always discovered ... or indeed, correctly attributed. It was nearly 10 years after the event that I discovered that the neurological condition which I had been experiencing was 'probably' the result of over exposure to free isocyananates during a single night of spraying polyurethane paints with the wrong grade of respirator (in the absence of any other explanation). There is also the possibility of compounded exposure where a single exposure does not cause harm but several over an extended period of time has an effect.

I'm not averse to using toxic substances and I'm not scaremongering or biased - if OA sublimation is your chosen miticide that's fine with me. My comments reflect my own stupidity in the past and its subsequent consequences ... I'm just suggesting caution - you won't be affacted by using appropriate PPE (apart from the financial implicaations) but you COULD be affected by not using appropriate PPE. It's a no brainer in my book; in comparison to what the vapourisers cost the respirator and eye protection are a small price to pay for your health.
 
respirator and eye protection are a small price to pay for your health.

Chemical warefare mask, £30 of course it makes sense.

The trouble is that the impact of exposure to such inoccuous airborne chemicals is not always discovered ... or indeed, correctly attributed.

Or diesel particulates etc...lol.
 
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Itma, can you provide any research papers/statistics on the numbers of beekeepers that have died, injured, directly as a result of treating their bees with oxalic acid sublimation...list of beekeepers names, in this country or others, actual facts.

Not as such.

There are safety limits, and sensible precautions.
I dare say that if you were questioning them, you'd go and dig into the research that lead to those safety limits being imposed.
I'm prepared to believe that this is a chemical that is nasty for humans - particularly as an inhaled vapour - without thinking that it is "scaremongering".
This is a chemical used outside beekeeping.
And in the wider world, there are guidelines for exposure limits.
Beekeepers are not so special that they are immune to the dangers that are acknowledged without question in 'real life'.

I don't have access to any statistics as to how many beekeepers ignore sensible safety precautions and what the numbers might be for long and short term consequences.
But then, I also don't have any statistics for how many people deliberately stick their hands into fires because they don't believe it is dangerous.


Treated with respect, and sensible safety equipment, the risk of harm should be minimal.
But treated casually, it is not just unpleasant, it is harmful - and potentially the consequences could be fatal.
It deserves respect.
It absolutely is not scaremongering to ask people to take great care when using it.
 
It absolutely is not scaremongering to ask people to take great care when using it.

I never thought that you were scaremongering Itma, and i also always advise others to use the appropriate protective gear.
 
I use a varrox vapouriser and have never had a problem.
I made my first vapouriser out of a travel kettle lol.

Common sense is needed as with any chemical treatment.

The large scale commercial vapourisers are a different item all together and need more safety equipment.

The biggest danger with a varrox as i can see is not cooling the pan before putting more OA into it. Thats why it tells you to dip the hot pan into a bucket of water after each treatment.

OA is dangerous and MUST be treated with respect but if used correctly is a very good way of dealing with varroa.

When i have treated my bees it says "leave the hive sealed for 10 mins" what i have found is after 10 minutes there is little or no vapour to escape as at normal temperatures the OA turns back into crystals.
 
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:iagree: Ditto to N.Coll above - Follow the instructions - stopwatch and bucket of cold water to cool unit between applications - simplicity itself. Can be a bit of a problem with some hive designs leading to having to place unit below floor mesh floor - manageable ...
 
However, advising people to ignore all standard safety advice and vaporise Oxalic without any person protection equipment whatsoever is the sort of thing that, outside internet forums, gets people sued.

:iagree:

Stupid and irresponsible I'd call it
 
you won't see the long term affects until it's too late and you end up carrying an oxygen bottle, or worst a member of your family has to carry it for you for your stupidity. Believe me that stuff makes you ill
 
you would REALLY have to work at it to harm yourself vapourising OA.

Don't believe that! Remember, 50% are below average.

Beekeeping is a basically simple affair, but look at how many that can muff it up!
 
I suppose my point is beekeeping is an outdoor activity and the vaporization is taking place in a sealed hive. So you have to work on getting a lungful, including leaving the mask off. But I can see the effects of such lungful might be nasty and permanent
 
Key point to remember here is that most "masks" would be ineffective.

They are usually designed to filter solids, (ie saw-dust) NOT Gaseous Poisons!
 

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