re: toxins in wax - I'm not the expert either but spend some time thinking about this
the toxins could be carried in on the pollen, the trees having been sprayed with something would necessarily have it on the flowers ergo pollen, which the bees then pack into the wax cells MAYBE over time would accumulate in the wax
The fact that the bees eat the pollen would suggest that lethal doses are likelier that way - if at all -
re: collapse disorder in general - my new hypothesis is that the commercial/industrial use and treatment of the bees is its' own worse enemy. Trucking bees thousands of miles has to be a major stressor on the bees. When they arrive at the new destination, possibly a place with pests and diseases they are not prepared for might be an incubator for diseases and the transmission thereof. Bees have to be intermixing with bees of other hives from other states etc which would be like putting your kid in school - which are major disease factories.
add to that the chemical treatments of diseases and you've done an awful lot of stressing to the bees. Add enough stressors and a black swan event could easily take down a hive, or thousands of hives exposed to the same set of precursor stresses.
OR
I'm full of excrement. All things are possible