13 research outputs found
Clinical and pathological study of an outbreak of obstructive urolithiasis in feedlot cattle in southern Brazil
Endotoxin, ammonia, and total and respirable dust in swine confinement buildings: the effect of recirculated air and respiratory protective masks
Caretakers and pigs in dusty environments
with particles and toxic gases may sustain
health consequences. We studied concentrations of ammonia, endotoxin, and total and respirable dust particles in four mechanically ventilated swine nurseries and two grower facilities using an ammonia sampler, filter, and British cyclone. In two of the nursery facilities, we determined the protection offered by respiratory masks that were mounted on glass funnels with filters or
British cyclones and sampled for dust. In
response to the increasing summer ventilation, large, nonrespirable particle concentrations in swine building atmospheres were reduced more completely by ventilation air movement than smaller respirable particles or ammonia. Total airborne endotoxin concentrations were similar to those eliciting pulmonary reactions. Total airborne endotoxin correlated with total suspended particles rather than respirable particles. Smaller respirable fecal particles enriched in endotoxin apparently stick to larger nonrespirable particles or are agglomerated before they became airborne. Internal recirculated air partially limited the mass concentration of
respirable particles in the breathing zone of
swine caretakers at lower but not higher
ventilation rates. Respiratory protection
limited the potential total dust exposures of
swine caretakers in such atmospheres (<25 %, 2-tie masks; <50%, I-tie masks of the total suspended particles). Respirable particles were reduced to <55% by 2-tie masks. Properly worn 2-tie masks protect against both large and small respirable particles in swine confinement facilities