I wouldn't suggest eating it unless you were positive of what it is. There are mushrooms out there that could make you seriously ill or make you expire completely.
It's also possible if you use too much fertilizer on the plants, they can react like this. In effect "burning" the leaves in a way.
If you haven't used any then of course that wouldn't be the reason. Greenfairy has a good point about watering them too. If you are in a really hot environment you may not be watering them regularly enough.
I want one! Well not really but it's a novel idea. They need customizable scents that you could control from a windows app! "Computer..please mix me Aqua Ocean with 30 sunscreen aroma"