I think beyondthesidewalks has pretty well covered most of the physical aspects of the turbines with exception to the "stray voltage". Which doesn't exist.
They may be referencing "EMF" instead, "Electromagnetic Fields" which are present around any type of electrical transmission lines or devices. We are all exposed to far to much "EMF" including the monitor you are sitting in front of and especially high voltage transmission lines. There may or may not be significant levels of EMF associated with the turbines collectively as they are connected to the collection grid. Provided you or your bees are located in close proximity of those lines. But I doubt that a very large amount of it would be present or transmitted from each turbine individually. Or at least I should say that there wouldn't be any more of a significant amount transmitted from them in comparison to conventional power transmission lines.
Does it effect the bees, sure it does as it does every living thing. How it effects them specifically I haven't a clue. But it's certainly not something new they are coming in contact with more or less depending one where you are located.
Given their short life span I wouldn't expect the long term effects we ourselves experience "cancer". But it would be interesting to know what if any effect it may have on their abilities and physical well being? But that would require remote isolation from all power sources to make a comparison and measure the effects of EMF on them.
"Success is not final, failure is not fatal: it is the courage to continue that counts." Winston Churchill