Hi!
I have actually never thought of this and i am not sure if i am preaching truth here (so fellow members, DO correct me when im wrong), but orchids are growing in the amazon, where discus originated from. However, the concentration of scent in the air of your room will probably be much higher...
I think (let me stress: THINK) that if you are not going to be using artificial scents and or plants that release toxic pollen you should be fine.
I am actually curious what the actual scientific answer is, so tag me when you get it!