Various people in recent posts have addressed the topic of sub lethal doses of pesticides.  I would like to remind everyone that there are few more meaningless phrases in the English language than sub lethal.  A surprising number of highly toxic substances simply have some lower dose where they are either no longer toxic at all or may even be essential ingredients of adequate nutrition.  Even low levels of radio activity may be good for you.  After all, epidemic studies show lower cancer rates in geographies with higher natural back ground levels of radio activity.  There is even some recent evidence that low levels of radio activity help the DNA repair chemistry work at its best.  A exact opposite finding to what common sense would anticipate.

It is quite common to think that dose response relationships are linear with amount of exposure.  The reason for this assumption is simple.  We have zero idea what the shape of the dose response curve is so linear is a simple and worst case assumption.  It is simple, worst case and probably always wrong.  It is also close to impossible to actually do experiments to determine the true shape of the response curve as it generally will follow some complex polynomial shape.  Doing actual experiments would involve so many thousands of test animals, each followed as an individual, that the time and cost would be far too high for even an academic study.  Further, even in a single species you will find each individual responding differently, at times radically differently, so in order to do a valid response test you would need to use highly inbred test animals.  Bees do not come close to fitting the inbreeding needs of an adequate test animal.

I have read several publications concerning the "irreversible binding of neonics" and find them totally unconvincing when the rest of the metabolism data known for this class of substance is also considered.  They look more like studies where authors have gone into the study with a conclusion already in mind and were very sure they would find they were right and willing to ignore anything that conflicts their idea.

Dick


" Any discovery made by the human mind can be explained in its essentials to the curious learner."  Professor Benjamin Schumacher talking about teaching quantum mechanics to non scientists.   "For every complex problem there is a solution which is simple, neat and wrong."  H. L. Mencken

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