Does anyone have any info about the amount and type of 'rare' materials that can end up in welding supplies?
I suspect that Thorium in certain materials represents a hazard?
thorium, cadmium, chrome, nickle are the major ones, thorium is not volatile
Read what the Health Physics Society has to say:
http://hps.org/publicinformation/ate/q1593.html
welding is gives less dose than smoking.