Not only do we need to know exactly which chemicals we are dealing with but also honest assessments of exposure levels as well. These of course will vary from event to event or track to track. As eddie stated, everything is toxic depending on the dose (among numerous other things). We can post all of the "data" we want about how harmful certain stuff is at certain levels, but the comparison can only be made when we know the exposre levels we experience.
Martin Crisp's reactions to paragon, though certainly unfortunate and alarming, seem to be the exception rather than the norm. Again like Eddie said... probably an allergic reaction.
I would feel comfortable saying that the norm is no short term or noticable adverse effects. I only say this because so many tracks use paragon and so many people are exposed for 8 or more hours every weekend. But even if the norm is some sort of adverse reaction I'd venture to say its the infamous paragon headache. Headaches alone though don't mean the stuff is harmful. I get headaches from certain smells, things not listed as harmful.
So to ask that everything be banned based not upon hard data, but rather one good guy's unfortunate reactions is a little over the top imo. It would be a decision rooted in emotion rather than logic and fact, which is understandable since Martin seems to be a well liked and certainly respected racer. Popular decision, perhaps, but not the right one. Get the data then make a decision.