[Evaluation of occupational exposure of copper welders]

Exposure of MMA/Plasma/Cu welders to fumes and soluble and insoluble Cu was assessed. Mean weighted concentrations of dusts/fumes and copper compounds at the welders' breathing zone were: 3.1 mg/m3 (0.7-7.6 mg/m3) for fumes; 0.08 mg/m3 (0.02-0.17 mg/m3) for soluble Cu; and 0.39 mg/m3 (0.08-0.76 mg/m3) for insoluble Cu. Correlation was found between the concentration of Cu compounds and fume/dust concentrations (r = 0.55 MMA/Plasma/Cu; r = 0.93 MMA/Cu). The mean percentage of copper in fumes/dusts was 17 (9.5-28.5%). Our results show that copper welding may pose a hazard to the welders' health. The index of combined exposure to determined agents was 1.2 (0.3-2.6), including soluble Cu (0.8) and insoluble Cu (0.4). The proportion of respirable fraction of fumes and their components varied between 40-80%. The background concentrations of the components (about 6 times lower than those in the welders' breathing zone) did not exceed the MAC value.