Increased Decline in Pulmonary Function Among Employees in Norwegian Smelters Reporting Work-Related Asthma-Like Symptoms

Abstract

Objective To investigate associations between work-related asthma-like symptoms (WASTH) and annual pulmonary function decline among employees of 18 Norwegian smelters. Methods A 5-year longitudinal study in which WASTH was defined as a combination of dyspnea and wheezing that improved on rest days and vacation. Results A total of 12,966 spirometry examinations were performed in 3084 employees. Crude annual decline in forced expiratory volume in 1 second (FEV1) (dFEV1) was 32.9 mL/yr (95% confidence interval, 30.5 to 35.3), and crude annual decline in forced vital capacity (FVC) (dFVC) was 40.9 mL/yr (37.8 to 43.9). After adjustment for relevant covariates, employees reporting WASTH showed higher dFEV1 by 16.0 m:/yr (3.4 to 28.6) and higher dFVC by 20.5 mL/yr (6.0 to 35.0) compared with employees not reporting WASTH. Conclusion Work-related asthma-like symptom was associated with greater annual declines in FEV1 and FVC, indicating a restrictive pattern.

Annual decline in forced expiratory volume is steeper in aluminum potroom workers than in workers without exposure to potroom fumes

“…However, a similar effect was not observed regarding dFVC. A similar effect was found among employees in the Norwegian Smelters [Søyseth et al, ]. We have, however, not been able to find any other studies where the association between the level of FEV 1 or FVC and their corresponding annual decline.…”

“…The analyzes of the complete follow‐up of the aluminum study was delayed because the authors who were involved in aluminum study (JK and VS) were invited by the Norwegian Smelter Industry to start a 5 year longitudinal study among 4,000 employees in 1996. The smelter study is recently completed [Søyseth et al, ]. Therefore, the final analyzes of the aluminum study postponed until we requested the Norwegian Aluminum Industry for completion of the aluminum study in 2012.…”

Do chronic workplace irritant exposures cause asthma?

“…An effect of chronic, moderate level exposures is suggested especially because episodes of accidental peak exposure are unlikely in the aluminium industry 39 . In a longitudinal study of Norwegian smelters, Soyseth et al found associations between dust exposure, mostly composed of nonspecific airway irritants, and the incidence of work-related asthma symptoms as well as an increased decline in pulmonary function 40,41 . However, it remains difficult to distinguish occupational asthma from work exacerbated asthma symptoms or occupational COPD among smelters 39,41 .…”

“…In a longitudinal study of Norwegian smelters, Soyseth et al found associations between dust exposure, mostly composed of nonspecific airway irritants, and the incidence of work-related asthma symptoms as well as an increased decline in pulmonary function 40,41 . However, it remains difficult to distinguish occupational asthma from work exacerbated asthma symptoms or occupational COPD among smelters 39,41 . In a recent longitudinal study in Northern Europe (RHINE), incidence of asthma and rhinitis were associated with welding 42 .…”

The Effect of a Knowledge-Based Intervention on the Use of Respirators in the Norwegian Smelter Industry

“…Depending on the end product and production processes, these exposure factors vary both qualitatively and quantitatively between smelters, but the respiratory risk they represent is of general concern for the industry. Previous studies conclude that Norwegian smelter workers are more susceptible to develop respiratory diseases such as chronic obstructive pulmonary disorder (COPD) than the general population (Johnsen et al, 2008;Søyseth et al, 2011Søyseth et al, , 2013Søyseth et al, , 2015. Although measures have been taken to reduce exposure, there are still areas and worktasks where exposure is too high and occupational exposure levels are exceeded.…”