Hi Aaron and All

> Continuing to shake the slim branch I'm on, I believe that honey more
> readily dissolves/absorbs/is contaminated by coumaphos and beeswax
> more readily is/absorbs/is contaminated by Apistan.

Hmmmn ... to a degree, but it is just safer to say that the usual acaricides
prefer to move into the wax but might be in the honey too.  As always, a
reference, it is just the way I was brought up ...

http://www.apis.admin.ch/english/pdf/BeeProducts/Acaricides_e.pdf
A 47kb file, for which you will need a PDF reader.

To try to distill the report, fluvalinate (Apistan) prefers brood comb over
honey/feed by a ratio of between 1800 and 10,000 (to one).  The other
chemical of interest here is coumaphos (Perezin) which prefers comb to
honey/feed by 300 to 2000 (to one).

When Apistan was permanently left in, a plateau of about 50 mg/kg in brood
combs was reached compared to an average of about 2 mg/kg when treated
normally.  Honey combs generally had 5-fold less than the brood combs for
fluvalinate, 10-fold less for coumaphos.  Some more facts: wax recovered
from comb slightly concentrates the contamination, and propolis from treated
hives has higher (3.4-fold) levels than the equivalent wax.

Although levels in extracted honey were very low, there was concern that the
strict German and Italian thresholds for coumaphos (0.01 mg/kg) would be
breached.

One more piece of data: the trend of acaricide contamination in wax samples
was followed over years.  Withdrawn acaricides were only slowly flushed from
the system.

What are the lessons?  Use properly and the residues in the honey will be
low.  Use or sell honey in the comb and there is more of a problem.  But
surely the greatest risk is to the image of honey if we put such things in
our colonies?

Gavin.