Bob Harrison wrote: " Researchers are puzzled that the 1ppb of imidacloprid detected in nectar & pollen could be the root of the problem. After all ppb of known higher toxic chemicals have been found and the bees *seemed* unaffected." The amounts found last summer in canola following treated potatoes were above 1 ppb. In wax it was 2 ppb which disturbs me. It also exceeded 2 ppb in honey and pollen in some samples. If the smoking gun you are looking for is dead bees at the entrance of a deadout I do not think you will find this with imidacloprid. I always am reminded of Bayer's own words when marketing imidacloprid as an ant and termite treatment: imidacloprid kills the colonies by weakening them and making them more susceptible to disease (slightly paraphrased to avoid me having to find the exact quote, which is very close). Also from Bob: "What is the problem if the problem is *not* being caused by imidacloprid" Bayer has now funded about a million Canadian dollars worth of study here and I am sure it would like to have found something to point to as the "problem". The syndrome has been documented, and I do not think that I have any mental blocks against accepting another cause or group of causes, but nothing has been proposed so far that seems plausible to me. Chris Slade wrote that viruses could be a cause of disappearing bees. I would like him to know that virus testing was part of the research and did not turn up anything there. I would like to mention that I have been told that the researchers would like to follow some of my hives this year as they move from wintering yards to blueberries to canola and if you have ideas for how to scientifically find "the smoking gun", then post them. My own thought is some test to determine which comes first, the diseased brood or the disappearance of adult bees. Hervé Logé wrote: " I was under the feeling pesticides intoxication is one more trouble bees have to face...." and ".... Or that bees could have passed through the winter if not exposed but exposure was too much for half of them." Both these paragraphs were very well expressed. I would add to his comments on pesticide acceptability for society that a pesticide with a half life of over a year cannot in my opinion be deemed acceptable. The testing here has always confirmed high residues in the soil and now shown that these residues are expressed in the succeeding crop years. The French found amounts in untreated sunflowers following treated sunflowers similar to those in treatment years in some cases, and the amounts found in New Brunswick in untreated canola following potatoes are similar to what Cynthia Scott-Dupree found in canola treated with imidacloprid in Ontario. "But I think bio-essays (i.e. proboscis extension response) to evaluate sublethal effects (that can lead to medium term disorder in the colony, or weakness that will make wintering a hazardous venture) are very recent (Pham-Delègue, 2002). " Thankyou for the reference for this Herve. If it would be possible for you to summarize the results of this paper, it would be much appreciated by me, and perhaps others who do not have access to apidologie, or have limited French. Bayer is very dismissive of some research regarding sublethal effects, but it is difficult for them to completely dismiss the research by Madame Pham- Delegue, because they have published pictures of her proboscis extension testing in their booklet on imidacloprid and bees and obvious consider her credible. Finally, I would like to make an observation after being involved with studies on imidacloprid and bees for a few years now. One problem that I see is the huge cost involved in every sample (it is about three or four hundred dollars per sample). With government cutbacks and user pay philosophy it makes it almost impossible to have research independent of Bayer funding. It should be possible to determine the ppb in a sample by using an appropriate short life span test insect instead of mass spectrometers and liquid chromatographs. So, for example, if you added known amounts of imidacloprid to diluted honey until you found the LD 50 (lethal dose for 50%) for fruit fly flies kept on that honey for two days, then why not use fruit flies to test honey samples after that. Or, maybe larder beetles could be used for pollen samples. Then, if you get samples that produce a killing dose you could measure the dilution possible to maintain the killing dose and extrapolate the ppb. In order to produce the most accurate result, the most highly sensitive organism should be chosen. I believe that some marine larvae like shrimp and lobsters are very sensitive, but they don't eat honey or pollen. Perhaps there is a winning science fair project for some young persons there! Regards Stan :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: -- Visit www.honeybeeworld.com/BEE-L for rules, FAQ and other info --- ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::