Randy wrote: Can you (or anyone else), please now provide supportive evidence (from any study) for the irreversibility of neurological effects from any of the neonics, from which we can then begin polite discussion? I changed the thread name. This will be, I hope, the polite and open minded thread. James provided an open access paper http://ncbi.nlm.nih.gov/pmc/articles/PMC4415021/ which shows a bioaccumulation of neonics in the brain over time which would tend to support irreversibility. Beyond that what the paper says about long term damage effects to the neurons is pretty alarming. The amounts used are field relevant. 2 ppb of imidacloprid is roughly what would be found in a field of canola that was UNTREATED with imidacloprid (treated instead with thiamethoxam) but was picking up imidacloprid from the previous years soil treatment with imidacloprid on potatoes. Bees weren't dying from the dosages given, but having neurological effects. Years ago Pham-Delegue showed neurological effects in honeybees at these dosages (and not sustained), but much cruder set up (proboscis extension test). Here is a second paper. Also open access (somehow came up from google scholar, apidologie papers are not usually open access for the first five years): http://scholar.google.ca/scholar_url?url=https://hal.archives-ouvertes.fr/hal-01003656/document&hl=en&sa=X&scisig=AAGBfm1-q9-68awzEoAXiCNRqIkLl6GCsA&nossl=1&oi=scholarr&ved=0CBsQgAMoADAAahUKEwiMr8yujuLIAhWFeD4KHcRjAg8 Neural effects of insecticides in the honey bee Luc P. BELZUNCES, Sylvie TCHAMITCHIAN, Jean-Luc BRUNET from that paper: The mechanisms by which neonicotinoids impair learning and memory performances may be more complex than expected. The metabolism of certain neonicotinoids in insects and plants results in the appearance of metabolites toxic to bees. In plants and in the honey bee, imidacloprid is transformed into different metabolites such as olefin and 5-hydroxyimidacloprid, which are toxic to the bees and are suspected to bind to the nicotinic acetylcholine receptor (Nauen et al. 2001; Suchail et al. 2001, 2004). The metabolism of thiamethoxam results in clothianidin, a metabolite as toxic as thiamethoxam that has been registered as insecticide (Nauen et al. 2003; Ford and Casida 2006; Benzidane et al. 2010). The toxicokinetics of acetamiprid in bees is somewhat different and leads to the appearance of 6- chloronicotinic acid. This metabolite is toxic in chronic exposure but not in acute exposure and remains stable for at least 72 h, especially in the head and the thorax (Suchail et al. 2001, 2004; Pages 353-354 have a discussion about receptor binding sites and dissociation constants that may be relevant to our discussion, but the work is with leaf hoppers not bees. Stan *********************************************** The BEE-L mailing list is powered by L-Soft's renowned LISTSERV(R) list management software. For more information, go to: http://www.lsoft.com/LISTSERV-powered.html