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Thread: Was: For readers of Beesource following Stromnessbees outburst

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    Administrator gavin's Avatar
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    Default Was: For readers of Beesource following Stromnessbees outburst

    Be patient, folks. I'm tidying up this thread to move the pesticide bits here. Must leave it now for a while ....

    What you find in this thread are the pesticide-related posts that arose in the thread of the above name, started by me in the 'Everything and anything' area. The posts relating to Doris' behaviour are still here.
    Last edited by gavin; 31-05-2012 at 07:28 PM.

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    Banned Stromnessbees's Avatar
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    Jon, by Harvard study do you mean this one?

    In situ replication of honey bee colony collapse disorder

    Chensheng LU1, Kenneth M. WARCHOL2, Richard A. CALLAHAN3

    Abstract

    The concern of persistent loss of honey bee (Apis mellifera L.) colonies worldwide since 2006, a phenomenon referred to as colony collapse disorder (CCD), has led us to investigate the role of imidacloprid, one of the neonicotinoid insecticides, in the emergence of CCD. CCD is commonly characterized by the sudden disappearance of honey bees (specifically worker bees) from hives containing adequate food and various stages of brood in abandoned colonies that are not occupied by honey bees from other colonies.

    This in situ study was designed to replicate CCD based on a plausible mechanistic hypothesis in which the occurrence of CCD since 2006 was resulted from the presence of imidacloprid, one of the neonicotinoid insecticides, in high-fructose corn syrup (HFCS), fed to honey bees as an alternative to sucrose-based food. We used a replicated split-plot design consisting of 4 independent apiary sites. Each apiary consisted of 4 different imidacloprid-treated hives and a control hive. The dosages used in this study were determined to reflect imidacloprid residue levels reported in the environment previously.

    All hives had no diseases of symptoms of parasitism during the 13-week dosing regime, and were alive 12 weeks afterward. However, 15 of 16 imidaclopridtreated hives (94%) were dead across 4 apiaries 23 weeks post imidacloprid dosing. Dead hives were remarkably empty except for stores of food and some pollen left, a resemblance of CCD.

    Data from this in situ study provide convincing evidence that exposure to sub-lethal levels of imidacloprid in HFCS causes honey bees to exhibit symptoms consistent to CCD 23 weeks post imidacloprid dosing. The survival of the control hives managed alongside with the pesticide-treated hives unequivocally augments this conclusion. The observed delayed mortality in honey bees caused by imidacloprid in HFCS is a novel and plausible mechanism for CCD, and should be validated in future studies.
    http://www.hsph.harvard.edu/faculty/...e-disorder.pdf

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    Senior Member Jon's Avatar
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    Yep. That's the one. There is a draft on the internet in Google documents but it is not due for publication until later in the year. I think it is the Bulletin of Insectology, a minor journal. That is the one I was referring to when I made the analogy about making someone drink 400 pints of beer as opposed to a normal amount.

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    Quote Originally Posted by Jon View Post
    Yep. That's the one. There is a draft on the internet in Google documents but it is not due for publication until later in the year. I think it is the Bulletin of Insectology, a minor journal. That is the one I was referring to when I made the analogy about making someone drink 400 pints of beer as opposed to a normal amount.
    Drinking 400 pints of beer is not a good analogy as surely one would switch to a higher concentration (e.g. whisky) rather than fill up the bladder unnecessarily.


    Anyway, in that study I cannot see a 400 fold increase in dosage in any treatment group. Actually, the increase is only 40 fold in 3 of the four groups.


    Could it be that you were mistaken in your criticism?


    Table 1. The weekly administration of imidacloprid in high-fructose corn syrup (HFCS) to honey bee hives1.

    Imidacloprid dosages (μg/kg)


    .................................................. .....1..............2........... 3............ 4............ 5

    Initial dosage (4 weeks) ------------10.5------ 5.3 ------1.1------- 0.1----- Control
    Amount of imidacloprid (μg) --------26------- 13 ------ 2.6------ 0.26------- 0
    Follow-up dosage (9 weeks) -------400 ------200------ 40-------- 20 -----Control
    Amount of imidacloprid (μg)
    -------1038----- 519 -----103.8----- 51.9 ------0
    http://www.hsph.harvard.edu/faculty/...e-disorder.pdf

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    Senior Member Jon's Avatar
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    Whiskey or beer, that is a lethal dose of ethanol!
    The thing is Doris, the level in Nectar and pollen is usually 1-2 ppb, on occasion up to 5ppb, so basing the levels tested on 20-400 proves nothing.
    Why do you think they changed from field realistic levels half way through, ie 0.1-10.5.

    I suspect that no effects were noticed at field realistic levels so they massively increased the dose.
    It is odd that a study moved the goalposts like this half way through.
    There is no explanation given for the change.
    This really is a poor study, possibly the worst of any I have read.

    The other thing is, only half of one percent of US corn is treated with Imidacloprid so the central premise of the study that Imidacloprid is the cause of CCD is clearly erroneous.

    Catch you later. Have to do some digging on my allotment.

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    Administrator gavin's Avatar
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    You can see Dr Lu in his own words in the presentation here. The man (*) taping the presentation contributes to Bee-L and has made plain his embarassment at his club's association with the work. What you see is a man (Dr Lu of Harvard) determined to prove big Ag in the wrong, yet who understands little of bees and beekeeping (or indeed GMOs). Yet the audience are enthusiastic about it - they are uncritical, happy that 'at last' here is a scientist willing to champion their cause.

    http://worcestercountybeekeepers.com...lapse-disorder

    I've never seen such strong criticism of a piece of scientific research on Bee-L. They ridiculed the link to CCD, the way the study was conducted and the interpretations of the researcher. And the response was not any kind of conspiracy, it is what happens when thoughtful beekeepers were confronted by poor science in an area they've been thinking deeply about for years.

    (*) Lest anyone start thinking of Dean as a 'Shill', do bear in mind that he is a host of this organic beekeeping conference:

    http://www.bushfarms.com/organic_beekeeping_meeting.htm

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    Quote Originally Posted by Jon View Post
    Whiskey or beer, that is a lethal dose of ethanol!
    The thing is Doris, the level in Nectar and pollen is usually 1-2 ppb, on occasion up to 5ppb, so basing the levels tested on 20-400 proves nothing.
    Why do you think they changed from field realistic levels half way through, ie 0.1-10.5.

    I suspect that no effects were noticed at field realistic levels so they massively increased the dose.
    It is odd that a study moved the goalposts like this half way through.
    There is no explanation given for the change.
    This really is a poor study, possibly the worst of any I have read.

    The other thing is, only half of one percent of US corn is treated with Imidacloprid so the central premise of the study that Imidacloprid is the cause of CCD is clearly erroneous.

    Catch you later. Have to do some digging on my allotment.
    Having been invoved in plenty of studies myself I would say that the way they proceeded was perfectly reasonable: For the first 4 weeks of the treatment they chose very small amounts of pesticide in reasonable increments, from 0.1 μg/kg to 10.5.

    Obviously they wanted to establish if there would be any immediate reactions at these doses. It would be counterproductive to kill off all your hives at the beginning of the study.

    After 4 weeks they went up to the next range of testing, from 20 μg/kg to 200. That way they can look for immediate reactions from 0.1 to 200 μg/kg with a minimum of effort, I think that was done quite elegantly.

    What is sad is that you made an error of a factor of 10 (you said 400 instead of 40) when you interpreted the data and then rubbished a perfectly good study and declared it 'the joke of the internet'.


    Also, as clearly stated in the abstract which I quoted earlier, this study has got nothing to do with nectar or pollen.

    It's about imidacloprid that had recently been introduced to corn plants and was therefore for the first time present in HFCS, a popular feedstuff of commercial beekeepers in the US. This coincided with the first reported outbreak of CCD amongst commercial beekeepers.

    The most important message from this study is that the treated colonies didn't die immediately but after a delay of about 6 months, there were 3 months between end of treatment and the first deaths.

    94 % of the treated colonies died from CCD like symptoms and 1 out of the 4 control colonies died, but from different symptoms ('dysentery').


    - Bad science or bad interpretation of perfectly good science?

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    Quote Originally Posted by Adam View Post
    Some of the science is poor (giving 200 - 400x the dose is one example)
    Did you by chance make the same mistake as Jon?

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    Quote Originally Posted by gavin View Post
    You can see Dr Lu in his own words in the presentation here. The man (*) taping the presentation contributes to Bee-L and has made plain his embarassment at his club's association with the work. What you see is a man (Dr Lu of Harvard) determined to prove big Ag in the wrong, yet who understands little of bees and beekeeping (or indeed GMOs). Yet the audience are enthusiastic about it - they are uncritical, happy that 'at last' here is a scientist willing to champion their cause.

    http://worcestercountybeekeepers.com...lapse-disorder

    I've never seen such strong criticism of a piece of scientific research on Bee-L. They ridiculed the link to CCD, the way the study was conducted and the interpretations of the researcher. And the response was not any kind of conspiracy, it is what happens when thoughtful beekeepers were confronted by poor science in an area they've been thinking deeply about for years.

    (*) Lest anyone start thinking of Dean as a 'Shill', do bear in mind that he is a host of this organic beekeeping conference:

    http://www.bushfarms.com/organic_beekeeping_meeting.htm
    What else was supposed to be wrong with the study?

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    Quote Originally Posted by gavin View Post
    Yes, they are neurotoxins just as most insecticides are. But they are well tested and don't affect bees at the levels they are exposed to normally, and the bees can and do metabolise it they so any effects are short-lived.
    Gavin, bees don't metabolise it, the effects are long term, as proven in the study.


    What you need to know is that once bees are finished nursing there is very little metabolising going on. They are not like mammals which replace more or less all their cells within a certain amount of time. They are more like little robots whose parts cannot be renewed.

    If the pesticide isn't in rather high concentrations, as it was in Britain and France when the big die-offs happened, the adult bee is not really affected.

    It's the developing brood that is affected, resultung in adult bees with damaged nerve system (unable to ward off varroa), immune system (susceptibility to nosema), hormonal system (Roger's queen problems) and reduced lifespan (CCD).


    What the weakened colony finally succumbs to depends on other external circumstances.
    - It's like having a colony with AIDS: any adverse conditions can finish it off.

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