Effect of layoff and rehire on respiratory variables of grain elevator workers.

A group of 77 grain elevator workers was examined at monthly intervals over a 7-month period. Approximately half of the workers were temporarily laid off for several months of this period, during which those who were steadily employed were involved in processing a reduced throughput of grain. The men who were laid showed a transient decrease in some respiratory symptoms during the months of layoff, followed by an increase after rehire. Those who were steadily employed showed a corresponding increase in these symptoms during the period of reduced grain movement, which did not change when the elevator returned to full activity. All of them demonstrated the greatest maximal expiratory flow rates during the midportion of the period of reduced work status, and the lowest values after either rehire or the restoration of full elevator activity. These longitudinal changes in respiratory variables are largely consistent with the effects of grain dust exposure, which may be at least partially reversible.