I think all of the above comments about reasonable precautions when using toxic chemicals are right on. I used Pyro as my LF developer for some time, until I got married and had kids running around. I was fortunate that I was trained in the safe use of hazardous chemicals and worked with things much more hazardous and in greater quantities than one ever would in a darkroom. What I find interesting about this discussion is that there are some very clear knowns about the chemical. First, it IS toxic. It has a high degree of oral toxicity with the lowest known lethal human dose being roughly 4.5 grams for a two hundred pound individual (if I did the math right). Second, it is a skin irritant, but probably not lethal. What does that mean to us? As it can be absorbed through mucous membranes (nose) and is a dermal irritant in its dry form, it is inherently safer to work with it in liquid form wearing gloves and if you chose protective eyewear. What is not clear in the studies is how long it remains in the body and develops a cumulative effect. If it remains potent in the body for thirty days your exposure risk to powdered pyro is greater if you mix developer on a daily basis. In either case if you work following a safe protocol the toxicity of the chemical should not be a significant risk factor to the average photographer.
for even more info to muddle the discussion
http://www.psi-net.org/msds/pages/pyrogallol.pdf
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