Respiratory effects of chronic animal feed dust exposure

Turkey-Aim-The aim of our study was to assess the prevalence of chronic work related respiratory symptoms and to determine lung function abnormalities in animal feed industry workers. Method-108 workers with a mean age of +/- SD: 32 +/- 7.11 yr employed in the animal feed industry and 108 unexposed subjects as a control group were enrolled in the study. All subjects filled out a questionnaire on their respiratory symptoms. Pulmonary function tests (PFTs) were conducted. Airborne dust (respirable fraction) was sampled during an 8-h work shift. Dust sampling was performed with a Casella AFC 123 machine. Results-A significantly higher prevalence of work related upper and lower respiratory tract symptoms such as cough (12%), dyspnea (5.6%) and sinusitis (8.3%) were found among the workers than in the control group (p=0.001, p=0.04 and p=0.008 respectively). Irritation symptoms such as pruritis of the eyes (11.1%), skin lesions (7.4%) and nose symptoms (8.3%) were also significantly higher among workers that in the control group (p=0.001, p=0.014 and p=0.005 respectively). The mean PFTs (predicted %) of the workers; forced vital capacity (FVC)% +/- SD (85.23 +/- 12.06), 1-s forced expiratory volume (FEV1)% SD (88.73 +/- 13.09), peak expiratory flow (PEF)% +/- SD (70.64 +/- 18.76) and forced expiratory flow rate at 25-75% of the FVC (FEF25-71)% +/- SD (88.42 +/- 25.94) were found significantly lower than in the control group (P<0.0001, P<0.0001, P<0.0001, P<0.0001 respectively). Our data indicate that exposure to animal feed dust is an important factor in the occurrence of respiratory symptoms and decline in lung functions.