Oh yeah, don't breath it in!!! You can feel it if you do. At the current time I spray in my bath tub with the window open, and the exhaust fan on. Not the best place, but a lot of times it is too windy or wet outside to attempt it.
Smkie, I had no idea about the markers!!! I use markers quite a bit, but they actually have no real smell (well, maybe a little bit, but its hard to notice). They are the tria letraset and prisma colour pantone markers.....I have felt light headed when using them, and normally open a window, but yikes, didn't know about the cancer causing!!