Impact of exposure to insulation wool on lung function and cough in Swedish construction workers

To investigate whether application of insulation wool adversely affects lung volumes and increases the occurrence of symptoms of airway irritation.

Data from nationwide health check ups in 1981-93 of male construction workers born in 1955 or later were used to investigate cross sectional (n = 96,004) and longitudinal (n = 26,298) associations between lung volumes, vital capacity (VC), and forced expiratory volume in one second (FEV1) and exposure to insulation wool by combining a job exposure matrix (JEM) and self reported exposure. Data on 12 month prevalence of persistent cough not associated with the common cold was available for the period 1989-92. Potential confounding from smoking, exposure to asbestos, silica, and isocyanates, was considered in the analyses.

For those in the highest exposure category (self reported duration of exposure of > or = 11 years, and high exposure according to the JEM) VC was on average 2.5 cl lower (95% CI -6.5 to 1.5) than in those with no exposure. The corresponding figures for FEV1 was -2.4 cl (95% CI -6.1 to 1.3). In the longitudinal analyses, the yearly change in VC between the first and last spirometry for those in the highest exposure category was 0.50 cl (95% CI -0.97 to 1.98) less than in the unexposed category. The corresponding figure for FEV1 was 0.89 cl (95% CI - 0.70 to 2.06). High exposure to insulation wool, asbestos, or silica, during the 12 months preceding the check up was associated with increased odds ratios (ORs) for persistent cough of the same magnitude as current smoking.

The results indicate no effects on VC or FEV1 from exposure to insulation wool. Recent exposure to insulation wool, asbestos, and silica was associated with an increased prevalence of persistent cough.