RESPIRATORY HEALTH AMONG RETIRED GRAIN ELEVATOR WORKERS

Previous studies of grain elevator workers have shown exposure-related increased rates for respiratory symptoms and reduced levels of lung function compared with those of other employed populations. However, some reports have suggested that this effect may be reversible after cessation of exposure. To investigate this, we conducted a respiratory health survey among 75 retired grain elevator workers and 37 retired civic workers. Methods included a standard respiratory questionnaire, routine spirometry, chest radiography, a 6-min walk test, and a specialized questionnaire to assess the impact of breathing trouble on the activities of daily life. Grain retirees were slightly older than civic retirees (69 versus 67 yr, p < 0.05) and less likely to be atopic (7 versus 35%, p < 0.01). Grain elevator retirees reported more dyspnea (44 versus 11%, p < 0.01) and had significantly lower levels for both FEV(1) (78.6 versus 88.2% pred) and FVC (90.0 versus 97.7% pred) (both p < 0.05). Compared with civic retirees, grain retirees reported the same average level of breathlessness after the 6-min walk test, but they walked a significantly shorter distance (p < 0.01); they also scored higher on the impairment of activities scale and had a greater proportion of persons reporting impairment of daily activities caused by breathing trouble (p < 0.05). Comparison of the changes in lung function from 1975 to the present study (i.e., from active employment to retirement) showed that grain workers had consistently lower levels of lung function than did civic workers while still employed, with no reversibility after retirement. We conclude that employment in the grain elevator industry may be associated with respiratory impairment that continues into the retirement years and that it may be responsible for respiratory disability and interference in the activities of daily life in some workers.