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Thread: Video lecture about risk profile of neonicotinoid insecticides

  1. #11
    Administrator gavin's Avatar
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    Thanks Alex, interesting comments. Here are some more of mine:

    Almost any biological effect of a compound increases with increased exposure time. There is nothing special about this. As I indicated before, imidacloprid does *not* bind irreversibly to acetylcholine receptors according to the literature, which makes his comparisons to carcinogens entirely spurious.

    The declines in biodiversity are huge issues and, as Alex pointed out, complex. Man is stressing the natural environment in many different ways. Pesticides could easily be part of that, but if we are to understand that it requires high quality unbiased science. It seems to me that Dr Tennekes has come to a personal conclusion that he knows the main reason for the losses he so rightly deplores, and is trying to marshal arguments that support that case. If what he does obscures the fact that the real reasons are complex and multifactorial, then he is doing everyone a disservice.

    Log-log plots. These are common devices to get straight lines out of biological data. I use them myself for other topics. There is no link to the action of carcinogens from that analysis.

    Ground water concerns: absolutely! There were concerns expressed in the US about groundwater contamination by imidacloprid, in New York I think. I remember commenting on them on Bee-L. Regulators that allow uses of toxins at such a rate as to contaminate their environment so completely are failing in their duty of care. You just shouldn't be allowed to use such compounds on such a scale on golf courses or whatever was contaminating groundwater in the US and in the Netherlands, in commercial bulb farming or potato growing or wherever the contamination is coming from.

    Surface water in the Netherlands. Why is Dr Tennekes citing 5,000 times the MTR in some samples - is that real? The map is scary enough, but that only shows 'over five times' the MTR. The MTR is 13 ppb, so is already close to the level which could harm wildlife, and five times that level indicates a serious problem that needs sorting right now!

    So my interpretation of this is that there sounds like there is a real underlying problem, maybe a really serious one, but unfortunately Dr Tennekes' intervention is not helping. Blow the whistle by all means, but don't do it by misunderstanding the issue and invoking spurious arguments.

  2. #12
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    [QUOTE=gavin;4220] Why is Dr Tennekes citing 5,000 times the MTR in some samples - is that real? The map is scary enough, but that only shows 'over five times' the MTR. The MTR is 13 ppb, so is already close to the level which could harm wildlife, and five times that level indicates a serious problem that needs sorting right now![QUOTE]

    I did not sit through the whole video but could the comma in the 5,000 have been the equivalent of our decimal point?

    Rosie

  3. #13
    Administrator gavin's Avatar
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    Hi Steve

    Good idea but not correct I'm afraid. The axis on the graph didn't use a comma. Three examples were cited showing 'factor above MTR' of around 700, 1700 and 4700. In the video he said 'nearly five thousand times' at one named location. It sounds like that level of contamination may be real, but I wonder what kind of surface water was involved.

    It seems to be the case that, because imidacloprid has low mammalian toxicity, it has been overused. I'm assuming that the Dutch Water Boards were conducting their analyses properly, but it would be good to know more.

    all the best

    Gavin

  4. #14

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    Hi All
    There seems to be a very strong pro pesticide opinion in this thread.

    Eric

    Rosie/Steve wrote:
    I did not sit through the whole video but could the comma in the 5,000 have been the equivalent of our decimal point?
    Gavin wrote:
    It sounds like that level of contamination may be real, but I wonder what kind of surface water was involved.
    Eric wrote:
    Surface water is surface water and as such it eventually discharges into the network of waterways.



    Eric wrote:
    Rachel Carson was the first to go into print about the burgeoning, destructive situation relative to pesticides – focusing in DDT. She came under vicious attack from vested interest in the pesticide industry; continuous attempts were made to destroy her and her credibility but ultimately DDT was banned


    Is Imidacloprid Harmful to Bees?
    by Eric Zeissstoff

    R. Schmuck in his report describes the following analysis results. Residues of 10 ppb at a soil
    depth of up to 10 cm correspond to a chemical burden of 45g Imidacloprid per hectare.
    "The evidence indicates that over a period of 6 years a relatively low level of Imidacloprid will
    be achieved [in the soil], namely 0.030 mg/kg". This corresponds to a level of 60g/ hectare.
    The persistent Imidacloprid soil residues of 45-60g/hectare have the ironic consequence for
    agriculture, that it is no longer necessary to apply new dressings of the pesticide to oilseed
    rape, since there is enough already in the soil from previous years to kill all earthworms and
    invertebrates.



    Jon wrote:
    There is not a single field study carried out anywhere in the world which has demonstrated that neonicotinoid pesticides are harmful to bees - and by God a lot of people have been motivated to try and demonstrate this.

    .................................................. .............................
    Alex wrote: In a meta-analysis of fourteen published studies of the effects of imidacloprid on honey bees under laboratory and semi-field conditions that comprised measurements on 7073 adult individuals and 36 colonies, fitted dose–response relationships estimate that trace dietary imidacloprid at field-realistic levels in nectar will have no lethal effects, but will reduce expected performance in honey bees by between 6 and 20%.’


    Zeisstoff wrote:
    It was further noted that no pollen was collected in the field where the rape had been treated
    with Imidacloprid, however in the test colonies in the untreated fields pollen was collected in
    large quantities. The evaluation of the test has indicated that bees affected by Imidacloprid
    suffer problems with orientation. Bees with a particular level of Imidacloprid contamination at 500 metres from the colony did not return to the hive at all.



    .................................................. ......................
    Eric wrote: I guess Zeisstoff walks with God!
    If you or I were either eating this stuff or feeding it to our livestock and getting this level of fall off - would we continue using it? No way! End of story! There is a glaring need for tighter regulations relative to world wide application of all pesticides. Instead of allowing the chemical multis to kill/maim or worse - the poor of the 3rd World, who are encouraged to apply this stuff as if it were snow or rain!

    ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
    Gavin wrote:
    Regulators that allow uses of toxins at such a rate as to contaminate their environment so completely are failing in their duty of care. You just shouldn't be allowed to use such compounds on such a scale on golf courses or whatever was contaminating groundwater in the US and in the Netherlands, in commercial bulb farming or potato growing or wherever the contamination is coming from.
    Surface water in the Netherlands. Why is Dr Tennekes citing 5,000 times the MTR in some samples - is that real? The map is scary enough, but that only shows 'over five times' the MTR. The MTR is 13 ppb, so is already close to the level which could harm wildlife, and five times that level indicates a serious problem that needs sorting right now!

    So my interpretation of this is that there sounds like there is a real underlying problem, maybe a really serious one, but unfortunately Dr Tennekes' intervention is not helping. Blow the whistle by all means, but don't do it by misunderstanding the issue and invoking spurious arguments.
    .................................................. ........

    Tenneke wrote: 'virtually irreversible blockage of postsynaptic nicotinic AcetylCholine-Receptors (nAChRs) in the central nervous system of insects.'
    Gavin wrote: I I found comments on the binding of imidacloprid to receptors, and it seems that you can wash off the imidacloprid within 20 mins with saline.
    .................................................. .........
    Talk about Ronald Reagan and “Bedtime with Bonzo” ! How about bath time for bugs?
    .................................................. ..
    C. Maus wrote:
    ‘After 10 years of research (C Maus et al Bulletin Insectology 2003 number 56, pages 51-57), it seems unlikely that imidacloprid was responsible for the French bee deaths.
    .................................................. ....
    Eric wrote:
    On the paper itself it is stated that Maus et al work for Bayer, the manufacturer of imadicloprid, in Germany and France. Form your own opinions!


    ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
    Last edited by Eric McArthur; 27-02-2011 at 06:35 PM.

  5. #15
    Senior Member chris's Avatar
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    Quote Originally Posted by Eric McArthur View Post
    Eric wrote:
    On the paper itself it is stated that Maus et al work for Bayer, the manufacturer of imadicloprid, in Germany and France. Form your own opinions!
    Eric, who do you think financed Bonmatin?Was it Teddy Goldsmith? Greenpeace? Maurice Mary?Would that make his work less honest?

    Mudslinging is not truth.It's certainly not worthy of someone who claims he is gravely concerned about the future of the world .

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    Senior Member Jon's Avatar
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    Quote Originally Posted by chris View Post
    Eric, who do you think financed Bonmatin?Was it Teddy Goldsmith? Greenpeace? Maurice Mary?.
    My guess would be Borderbeeman!! He never shut up about Bonmatin's ten year old study in spite of the fact that thare are many more recent studies which do not support his preconceived ideas, or Eric's either for that matter. The other obsession was the fact that Bayer in its previous incarnation made Zyklon B. Oops, nearly let the cat out of the bag about Bonmatin's sponsor. Mentioned it once but I think I got away with it.


  7. #17

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    Eric,

    I’ve read the Eric Zeissstoff article you kindly translated which contains a few ‘yet unanswered’ and ‘could possibly be higher at point of harvest’…. if you have any source articles alluded to in the report I would be glad if you could post them (or email).

    Apart from ending with a plug for a book the Tennekes pdf attachment doesn’t really add much to the debate other than raising questions about the Dutch Water Board’s management of what is presented as contamination of epic proportions. Given the slides’ contain data from 2006/2007 I would have expected a serious environmental debate to have ensued in Holland and across Europe by now on the back of that information. I don't want to appear dismissive, perhaps I was expecting something more rigorous in tying species decline to neonicotinoids.

    In terms of the honeybee debate I think we need to decide on what we mean as ‘harmful’ otherwise we will go round in circles. I believe from your posts that you use, or have used, Oxalic Acid and perhaps miticides to treat your bees. In that vein, beekeepers are happy to pour Oxalic Acid into their hives which can have a harmful physiological effect on their stock and in the same season use miticides (Apistan, ApiLife Var etc) which are reported to reduce drone sperm production without any real adverse comment. Do you consider these harmful to honeybees?

    Neonicotinoids will have an effect on non target invertebrates such as honeybees; from what I can gather these affects in field trials are classified as sub-lethal e.g. disorientation. Does that make them ‘harmful’ in terms of mortality to honeybees and other species? There are very many reports supporting the sub-lethal hypothesis when neonicotinoids are used correctly. I’m not saying it’s a satisfactory situation but may be a risk humankind will have to accept when considering food production.

    I’m not pro anything, I’m just not convinced by the information I’ve been presented with to-date for the immediate banning of neonicotinoids. What I have noted is the implied lack of humanity for our flora, fauna and environment if I do not accept without question the anti-pesticide argument. In an ideal world we wouldn’t need pesticides; that world hasn’t existed for some millennia.

    If this thread can be kept on track I'm sure we'll all learn a lot about the use and effect of neonicotinoids as well as the informed opinions of beekeepers here and abroad.

    Keep up the good work,

    Alex

    p.s. apologies for the incorrect spelling of the dreaded pesticide in my earlier posts, and being new to the internet forum scene please tell me if my posts are too long or rambling.

  8. #18
    Senior Member Jon's Avatar
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    Alex. I think more in depth analytical posts are exactly what is needed in this debate. Some parties are open minded, but some have already made up their minds and are unlikely to change their views no matter what evidence is presented.
    I also have difficulties with Tennekes claims - as he seems to imply that because the decline of some bird species broadly coincides with the introduction of neonicotinoids, the former must be caused by the latter. It's pretty obvious to me that there are many factors such as general habitat decline which could also be major factors. Notwithstanding other risk factors, modern agriculture/monoculture, including excessive pesticide use is likely to be stressing many species. A recent UK Government discussion document looked at ways of increasing food production without bringing more land into general agricultural production and reducing habitat even further.

  9. #19

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    Jon,

    I agree there's so much emotion generated around the topic that much of the common sense debate gets buried in a smokescreen of emotion; you're video clip was spot on.

    While I'm capable of carrying out my own research (albeit with no background in genetics, biochemistry or toxicology) I'll undoubtedly miss some of the finer detail, context or links between important pieces of work. In that respect I'm ever hopeful that those who are more knowledgeable and experienced will stick their head above the parapet and get involved.

    Alex

  10. #20
    Senior Member Jon's Avatar
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    Those who shout the loudest are not necessarily right, in fact their words often turn out to be complete hubris.
    I instinctively mistrust anyone who tries to reduce a complex issue to tabloid soundbites.
    It's important to get at the truth - and not be swayed by those who just 'know' they are right even though the available evidence does not support their position.
    There is good debate to be had re. pesticides on this forum, the Irish forum, the Bbka forum and the Bee-L forum.

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