here is a page you might want to read:http://www.bjornapiaries.com/gmoneonicotinoids.html
As usual, most of the discussion of late is whether certain chemicals, and practices that GMO utilizes in food production, is the result of CCD.
No single chemical can be directly blamed for all the CCD. So many stand behind that notion, that CCD is not caused by corn production or some individual chemical, and it is therefore concluded that these chemicals and practices are not harmful to bees.
Long before CCD, pesticides and chemicals used in farming were an issue for beekeepers and bees. Just because one chemical or another can not be solely held responsible for all CCD, does not mean there is not a real harmful effect on the bees.
And not all effects of chemicals results in outright death of a colony overnight. But it may play a part in lower honey production, smaller clusters to survive the winter, and a host of other impacting items that may result in a colony death.
One study has claimed to debunk any responsibility of CCD or harmful effects of certain chemicals by showing that bees can "recoup" and repopulate any lost bees and brood. Like that is what any beekeeper wants....a hive constantly losing half of it's bees, and not able to produce honey. And the study did not continue into the winter to track hive loss. They simply said "Hey look! This colony only lost half it's bees, and was able over time to repopulate it's numbers, so any hive loss is not this chemical or pesticides fault". And if the colony died later due to low winter cluster numbers or the bees eating stored tainted pollen, it was not noted or realized.
Beekeepers and their inability to organize, fight, influence, or do much other than be sheep being led to slaughter, means you as an individual needs to find better locations to keep your bees. And in some areas, beekeeping simply is not an option. Location, location, location....is more important than ever.