> none of these countries has high HMF levels in fresh honey. 
> High HMF levels occur in tropical honeys and old honey.

This side-issue argument about "fresh honey" overlooks the fact that it does
not take long at all for HMF levels to increase in honey WHILE STILL IN THE
SUPERS for very reasonable periods of time at not unreasonable/unusual
summer ambient temperatures.

Quoting a practical source of info for the commercial beekeeper
(https://airborne.co.nz/hmf.shtml):

"Honey that is traded in a bulk form is usually required to be below 10 or
15mg/kg to enable further processing and then give some shelf life before a
level of 40 mg/kg is reached. It is not uncommon for honey sold in hot
climates to be well over 100 mg/kg. This is mostly due to the ambient
temperatures (over 35°C) that honey is exposed to in the distribution
channel."

Time for 30 mg/kg HMF to accumulate (based on 3 samples):

30C (86F) 	100-300 days
40C (104F)	20-50 days

I can get 104F in a honey super with ease starting at the end of June.  So
can nearly anyone in locations where bees can overwinter without
extraordinary measures (such as wrapping hives or indoor storage).

So, by simply not harvesting until the end of July on one of my rooftops in
NYC rather than harvesting more promptly at the end of June could result in
20 days of rooftop supers of honey subjected to 104F.  I shudder to think
what the temps were in my VA hives, even with all sorts of top venting
employed.  They were higher, for sure.

It is the MAXIMUM temperature IN THE SUPERS that matters in regard to HMF.

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