Endotoxin and β-(1 → 3)-glucan exposure in poultry and ruminant clinics

Background: Exposure to organic dust is a well-known hazard for farm animal workers leading to respiratory diseases. Organic dust exposure has not been adequately evaluated in environmental settings in relation to veterinarians. Objective: To investigate inhalable dust, endotoxin, and β-(1 → 3)-glucan exposure among caretakers, veterinarians, and veterinary students. Task-based determinants of exposure were studied. Methods: This study investigated the exposure during veterinary education in the ruminant and poultry clinics. Dust measurements were performed using the conical inhalable samplers (CIS). Endotoxin and β-(1 → 3)-glucan were determined by the kinetic limulus amebocyte lysate (LAL) assay and inhibition enzyme immunoassay (EIA), respectively. Determinants of exposure were identified by multiple linear regression analysis. Results: Personal exposure levels of dust, endotoxin, and β-(1 → 3)-glucan were higher for poultry [geometric mean (GM): dust, 1.32 mg m⁻³ (below the lower limit of detection (<LOD) to 20.9); endotoxin, 1498 EU m⁻³ (115–49 846); and β-(1 → 3)-glucan, 3.10 μg m⁻³ (<LOD–46.1)] than for ruminant settings [GM: dust, 0.60 mg m⁻³ (<LOD–20.8), endotoxin, 520 EU m⁻³ (60–7492), and β-(1 → 3)-glucan, 3.39 μg m⁻³ (<LOD–111)]. Dust and endotoxin levels correlated significantly when stratified by work-sites and job-titles, except for caretakers in the ruminant clinic. Modeling of task-based determinants revealed some activities to be associated with higher exposure, but tasks were dependent on the job-title. Conclusion: This study showed substantial endotoxin exposure in modern animal clinics. Exposure occurred not only in animal houses, but also in practical teaching rooms. β-(1 → 3)-Glucan was substantial as well. Observed exposure levels might present an occupational respiratory health risk for veterinary populations.