Video lecture about risk profile of neonicotinoid insecticides

[KMBonn]

Dear fellow beekeepers,

on Frebruary 16, 2011, the dutch toxicologist Dr. Henk Tennekes gave a lecture at the Institute of Public Health, University of Heidelberg (Germany). This lecture is about "Toxicity as function of exposure time - Risk profile of neonicotinoid insecticides".

It was originally given in german, but yesterday I visited him to record an english version of his lecture for the international beekeeping community.

You can see and listen to this video on youtube:

http://www.youtube.com/watch?v=M4RIDWuCN-A

Greetings from Germany,

Klaus

[gavin]

Thanks very much for sharing this Klaus, very interesting. It certainly gives a perspective on environmental pollution that needs to be taken seriously. I guess that over the coming days and weeks we will be discussing the implications of the talk here.

Do you know where we can see the raw data or better quality slides for the Dutch Water Boards study of imidacloprid in surface water?

best wishes

Gavin

[KMBonn]

Hi Gavin,

Dr. Tennekes gave me some sheets and in the later evening I'll change it to pdf and upload it to my server. I will post a message.

Greetings, Klaus

[Stromnessbees]

Well, I know I have gone awol for a while, but for this thread it seems worthwhile to creep out of the woodwork.

For those who don't have the patience to watch the whole video I have copied the page with the conclusions (from 25:41):

Conclusions:

• The mode of action of neonicotinoid insecticides derives from almost complete and virtually irreversible blockage of postsynaptic nicotinic AcetylCholine-Receptors (nAChRs) in the central nervous system of insects.

• The toxicity of neonicotinoids to arthropods is reinforced by exposure time. Their dose : response characteristics are strikingly similar to those of carcinogens. Thus, there may not be a safe level of exposure.

• Imidacloprid is persistent and mobile in soil and prone to leaching.

• The contamination of surface water with imidacloprid is massive in some parts of Holland.

• Of the 13 components of agricultural intensification, only the use of insecticides and fungicides had consistent negative effects on biodiversity (wild plant, carabid and bird species).

• Surface water contamination with Imidacloprid correlates with reduced Diptera (Flies and Midges) abundance.

• Strong decline of butterflies since the introduction of neonicotinoid insecticides.

• Many invertebrate-dependent bird species (in very different habitats) are declining, some are now extinct.

As Gavin points out, the quality of the clip is poor, so if you want to just watch the essence of the talk rather than an extended chemistry lession, I recommend listening from 12:20, when he gets to the biological implications for insects and birds.

http://www.youtube.com/watch?v=M4RIDWuCN-A

So, as there 'may not be a safe level of exposure' to neonicotinoids, what are we going to do?

[KMBonn]

Here's a pdf given by Dr. Tennekes: http://www.farmlandbirds.net/sites/d...0English_0.pdf

Greetings, Klaus

[Stromnessbees]

Hi Gavin, could you please post the link from post 8 again, at the moment it's not working.


If we are now discussing where we all stand when it comes to peticides I would love to say that we should get rid of them all. But I can't say that as even I use them:

1. On our organic farm we give one drench of sheep wormer to the ewes at lambing time before they are moved to 'clean grazing'. Also, if lambs fail to thrive we can do a worm-egg-count and dose them if the numbers are high.

2. My cat also gets the occasional treatment with a pesticide against fleas.

3. And then there's of course my indirect use when buying food etc.

I try to minimise negative effects though by buying organic foods when I can, and the cat has to live with the occasional flea.

On the farm the choice of pesticide is very important though. Our prefered wormers for the sheep are old fashioned non-systemic ones which (as far as I could find out) do not persist in the dung and therefore won't disrupt the breakdown of the dung in the field and negatively affect wildlife.

However, the newer wormers (Avermectins) are used by many livestock farmers routinely and can have detrimental effects on arthropod numbers and therefore for example lead to a decline in bird numbers in otherwise pristine looking landscapes.

To allow farmers to make the right decisions the facts presented about pesticides need to be correct and easily available, and this is where we seem to have a major shortfall. Especially the persistency of a pesticide should be a very critical element in its evaluation.

I am also wondering why neonics wouldn't be harmful to mammals if they block receptors in synapses which are very similar in arthropods and mammals. Any explanations?

[chris]

I am also wondering why neonics wouldn't be harmful to mammals if they block receptors in synapses which are very similar in arthropods and mammals. Any explanations?

Hello Doris, I don't have the necessary scientific knowledge to answer that question, but before being allowed on the market a pesticide must undergo many tests for its possible effects on mammals. In the case of the active element fipronil, the following may be helpful ?

http://www.affaire-gaucho-regent.com...sa_summery.pdf

Regards.

[gavin]

Hi Gavin, could you please post the link from post 8 again, at the moment it's not working.

Sorry Doris, I boobed. The link is fixed now in post 8 and is also here.

[Eric McArthur]

Stromness wrote:
* The toxicity of neonicotinoids to arthropods is reinforced by exposure time. Their dose : response characteristics are strikingly similar to those of carcinogens. Thus, there may not be a safe level of exposure.
* Imidacloprid is persistent and mobile in soil and prone to leaching.
I recommend listening from 12:20, when he gets to the biological implications for insects and birds.
http://www.youtube.com/watch?v=M4RIDWuCN-A
So, as there 'may not be a safe level of exposure' to neonicotinoids, what are we going do?
.................................................. ......................
Hi Doris
What to do? Ban the offending material! As I have been advocating for many years!
Chris Connolly’s pending important research should highlight just how much Scotand’s bee are at risk for the burgeoning use of these toxic systemic neonicotinoids

Eric

[Jon]

What to do? Ban the offending material! As I have been advocating for many years!

Just remember that if you ban neonics you are in effect voting to bring back organophosphates, carbamates and pyrethroids.

Doris and Eric. I would be interested in hearing why you think it is better to use these older pesticides rather than neonicotinoid pesticides. we live in the real world and pesticide use will continue even if neonicotinoids are banned. Neonicotinoids are also known to be much less harmful to one important species - the human. Pity the 3rd world agricultural workers who are obliged to spray much more dangerous chemicals on crops and also over themselves in the process.

It's easy to get on your high horse if you don't have to live with the consequences like some others have to.

So, as there 'may not be a safe level of exposure' to neonicotinoids, what are we going to do?

Tennekes is just one opinion and it is by no means mainstream.
There is an overwhelming body of evidence which suggests that neonicotinoids are not particularily harmful to bees and other pollinating insects.
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.
We wait on the C Connolly study with bated breath, but the design looks to be much less rigorous than many which have been carried out before, so it is debatable what it might show. As Roy Keane said when he walked out of Ireland's doomed 2002 world cup campaign. Fail to prepare, prepare to fail!