Proposal of a dose-response relationship between aluminium welding fume exposure and effect on the central nervous system.

Exposure to high levels of aluminium can affect the human central nervous system. Abnormalities of psychomotor function have been observed among haemodialysis patients with mean aluminium concentrations in serum of about 60 micrograms/l. According to our own data this corresponds to a urinary level of about 330 micrograms Al/l in aluminium-exposed welders without kidney failure. This post-shift urinary level of aluminium is estimated to be attained after 40 years of exposure to a welding fumes at an environmental concentration of approximately 1.6 mg/m3 of aluminium. An increased prevalence of effects on the nervous system was observed among welders exposed to aluminium fumes for more than 13 years. This finding supports the concept of cumulative toxicity due to aluminium exposure. On the basis of these observation, we suggest that the level of aluminium in welding fumes should not exceed 1 mg/m3.