I see many people have mining rigs in their rooms, some with 6+ gpu's. Is the air quality bad? I know that heated solder is bad for you. So, isn't it unhealthy to breath in too much of the air coming out of a mining rig?
It really is no different than running a few computers in your home or office, same components. The miners may run a bit warmer and heat up and dry out your air, but other than that no real bad effect should come of it. As was mentioned, there may be some new component smell the first few weeks, but again that would be no different than any other new electronics in your house. If you are really concerned open up a window for some fresh air.
There may indeed be an increase in the RF noise floor which can cause some some other radio devices in your house to not function properly (RF remotes, WIFI, TV (off air) reception) but this usually only manifests once you get 20-30 GPUs running in a close area. I do not really think they will cause any health issues unless you are sleeping or living right next to a bunch of GPUs 24/7. By that I mean you would need to be within a couple of feet at all times, since RF radiation adheres to the inverse square law meaning every doubling of distance between you and the RF emitter, the power level decreases by a factor of 4. So the RF power at 2 feet will be 1/4 that of 1 foot, and the power at 4 feet will be 1/16th that and so on. If you put an obstruction in the way, such as a wall, this increases even more so just keep them in a separate room than where you spend a lot of you time.