[Epidemiological studies on the occurrence of lung diseases in welders].

A cross sectional study in electric arc welders revealed significant higher prevalences of simple chronic bronchitis and of nodular opacities in thorax x-rays in spite of exposure below MAC in most cases. Spirometry, flow-volume-curves and bronchial challenges with acetylcholine showed no substantial functional deterioration in comparison with controls. But there are weak dose-response-relations between symptoms as well as lung function data on the one hand and duration of exposure as well as welding fume concentration on the other hand.