Induced sputum abnormalities in gas station attendants

To investigate inflammatory changes in the induced sputum (IS) of gas station attendants (GSAs) at risk of exposure to fuel vapors through inhalation and susceptible to respiratory complaints and impaired lung function.

Hypertonic saline-IS was collected from 52 GSAs who had never smoked (42 men, age = 35.9 ± 8.9 years) and had no known comorbidities. A group of 22 non-smokers (11 men, age = 30.5 ± 5.1 years) selected from the University staff served as control. The GSAs answered a questionnaire and underwent spirometry and chest tomography. A total of 15 inflammatory biomarkers associated with inflammation, including cytokines, chemokines, and mediators of immunological response, were also measured.

The most common symptoms of GSAs were coughing (42.3%) and dyspnea (59.6%) based on the New York Heart Association (NYHA; Class II) classification. Significant elevations (p < 0.05) in forced vital capacity and forced expiratory volume within the first second were observed in the GSAs relative to those in the controls (GSA vs. control: 99 ± 12% vs. 90 ± 9% and 94 ± 11% vs. 87 ± 10%, respectively). The GSAs had a lower percentage of IS lymphocytes than that in the control group (4.5 ± 5.7% vs. 7.7 ± 9.8%). The GSAs also had significantly lower concentrations of IL-4, IL-5, IL-10, IL-12_P70, IFN-γ, and MIP-1α, but IL-3 levels were higher. No differences were observed in the airway thickness and the amount of emphysema between the GSAs and the controls.

Despite normal lung function and absence of abnormalities on HRCT, GSAs have a higher frequency of respiratory complaints, with evidence of impairment of lymphocytic activity in the airways.