When harvesting I used a product called Bee Dun and a fume board on my first hive only. It worked and smelled pleasant but I noticed it had an almond smell. Since my family has nut allergies I did not want any possible nut contamination to my honey so I separated the frames from the first hive and the remainder hives. My daughter emailed the company to inquire if the product does have any type of almond or nut oils in it and we did not receive a response. I don't know if this or other similar products have ingredients that may impact individuals with severe allergies but I thought it should be mentioned. It would seem that the possibility of any contamination is slight but that all its takes to make someone with severe problems very sick.It would be very helpful if the manufactures of these products disclosed the actual content of their products so that we could be informed before using them. As for myself I have discontinued the use of any of these products until I have more information about their actual contents.