title: Characterization of particles, ammonia and endotoxin in swine confinement operations.
abstract: To define the atmospheres swine confinement operations, we measured concentrations of total and respirable dust particles, ammonia and endotoxin in the nursery and grower areas of 4 swine confinement houses. Increased ventilation in spring-summer relative to that in winter reduced concentrations of large dust particles more rapidly than it did smaller particles or ammonia. The greater decrease in large particles correlating to increased room air velocity may reflect larger particles' momentum causing impaction on surfaces. There was significant spatial variation in the concentration of airborne endotoxin within individual swine rooms and pens reflecting different mixing of large feed and smaller manure particles. Smaller particles had 4-fold higher concentrations of endotoxin than did larger particles, suggesting they had higher fecal material concentrations. Total airborne endotoxin and total suspended particulates correlated to the fraction of functional endotoxin contained in large particles, suggesting that small particles (0.5-2.0 micrometers) collide with large particles (50 micrometers). These data suggest that large non-respirable particles remove smaller respirable particles from indoor atmospheres due to kinematic coagulation.
authors.affiliation: Department of Clinical Sciences, Abilene Animal Hospital, PA.
authors.forename: J A
authors.initials: JA
authors.lastname: Pickrell
authors.forename: A J
authors.initials: AJ
authors.lastname: Heber
authors.forename: J P
authors.initials: JP
authors.lastname: Murphy
authors.forename: S C
authors.initials: SC
authors.lastname: Henry
authors.forename: M M
authors.initials: MM
authors.lastname: May
authors.forename: D
authors.initials: D
authors.lastname: Nolan
authors.forename: F W
authors.initials: FW
authors.lastname: Oehme
authors.forename: J R
authors.initials: JR
authors.lastname: Gillespie
authors.forename: D
authors.initials: D
authors.lastname: Schoneweis
mesh_terms: D016902:Air Pollution, Indoor / Q000032:analysis*; D000641:Ammonia / Q000032:analysis*; D000822:Animal Husbandry; D000818:Animals; D004391:Dust / Q000032:analysis*; D004731:Endotoxins / Q000032:analysis*; D006799:Housing, Animal; D012621:Seasons; D013552:Swine; D014691:Ventilation
chemical_list: D004391:Dust; D004731:Endotoxins; D000641:Ammonia