Hey,
If you had a hive out for pollination and they were all killed after a spraying, would any of the equipment be usable again?
Most of the modern insecticides are short lived. If you leave it out in the rain and sun for a month or so I would think it would be fairly safe.
I wouldn't have a problem reusing the boxes after a few weeks in the weather, but the frames and wax may still be contaminated. I'd destroy the frames. Might be overkill but frames are cheap.
Make sure you cover yourself and your equipment for loss ($$$) in your pollination contract with the grower.