Pulmonary function in aluminium smelters

Two studies were conducted at an aluminum smelter employing 113 male workers in the smelting process. Twenty one of the 111 men in the first study experienced chest tightness more often than once a week and had a higher prevalence of cough, dyspnoea, and nasal symptoms but not of positive skin test responses than symptomless men. Lung function in these men did not differ significantly from that in the symptomless men at the beginning of the working week and only marginal deterioration occurred over the week. In the second study serial spirometric measurements were obtained over several shifts in a subset of 31 men from the first study. Impairment of ventilatory function on exposure to smelting fumes was demonstrated in 18 men. Analysis of all data from the 31 subjects revealed that ventilatory function varied significantly in association with heavy exposure to potfumes and a history of recurrent chest tightness. The findings of these two studies indicate that aluminum smelting fumes can cause bronchoconstriction in susceptible individuals. The reaction is dose dependent and is more severe in those with a history of recurrent chest tightness.