> any guesses on what was by far the most common pair of chems? - Fluvalinate & amatraz the two most widely used varroa mitacides in the WORLD. In the 1987 book "The varroa Handbook" which listed the top 100 chemicals which were known at the time to control varroa those were the two deemed the safest as far as honey contamination and safe for the bees. Both had been in use for a few decades before then. If your hypothesis was true Brian then why are millions of hives around the world doing just fine on comb which has those levels of those chems? Randy Oliver and I have pondered the question and it seems to me that bees can tolerate a very high PPM of those chems. Also what I was told by Beltsville. Not keeping control of varroa and not keeping a handle on nosema has killed far more hives in the U.S. over the last decade than comb contamination from fluvalinate than amatraz. If you had been with me the last decade looking over my shoulder you would believe the same but you have not so we will have to agree to disagree! the beekeeper which you speak of main mistake was not to contact me first instead of Beltsville. When we did speak Beltsville was his source of information. I would have set the test up very different than they did. Not a single control hive on foundation! I believe he has a comb problem but also believe its caused by something other than the high levels of fluvalinate and amatraz found in his comb. When he said he was going to radiate his comb (asked me if I wanted some comb done) i advised to do as BELL Honey had done and replace comb. He chose to listen to Beltsville. Bell Honey burned comb in Florida (with permits) for two months solid. Three and a half million frames . Now he is back to square one as the money spent to radiate the comb seems now (at least to me ) a waste. If he had torched the inside of those boxes and started on new foundation those package bees I believe he would not be having the problem. I have never been attached to old dark 30 year old comb but I have got friends which will not replace comb. In spring in Texas you can warm yourself by the frame bon fires of Darrel Ruford and other large operators. I do not have frames of comb on which fluvalinate of coumaphos have been used and the bees look great. However I can take a ride across town and show you hives of bees which look as good as mine and the beekeeper has only used chemical strips for the last two decades. bob -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean. **************************************************** * General Information About BEE-L is available at: * * http://www.honeybeeworld.com/bee-l/default.htm * ****************************************************