As I carpenter for the past 20+ years or so, I can honestly say that most of the warnings regarding various woods appear to be somewhat overblown. Heck, for most of those years the predominant wood around here for building was redwood, and other than it staining your hands, I saw nobody in the trades who had ever had any adverse reaction to it (or any other woods, including exotics) even after being coated with it head to foot on a daily basis. And very few folks used dust masks back then either. Now that I've gotten older (and wiser, one would hope) I use a dust mask and/or respirator all the time, (and I would advise everyone else to also) when they are exposed to any kind of dust ...regardless of it's source, but the point is that wood is about as benign a material as one will encounter in this day and age.
Are some people sensitive to various woods? I suppose so. But there are plenty of more toxic chemicals in the carpet that you walk on in your house then in the majority of these purportedly 'hazardous' woods.