Endotoxin and dust at respirable and nonrespirable particle sizes are not consistent between cage- and floor-housed poultry operations.
BACKGROUND
Individuals engaged in work in intensive animal houses experience some of the highest rates of occupationally related respiratory symptoms. Organic dust and in particular endotoxin has been most closely associated with respiratory symptoms and lung function changes in workers. It has previously been shown that for intensive poultry operations, type of poultry housing [cage-housed (CH) versus floor-housed (FH)] can influence the levels of environmental contaminants. The goal of the study was to determine the differences in endotoxin and dust levels at different size fractions between CH and FH poultry operations.


METHODS
Fifteen CH and 15 FH poultry operations were sampled for stationary measurements (area) of dust and associated endotoxin. Fractioned samples were collected utilizing Marple cascade impactors. Gravimetric and endotoxin analysis were conducted on each of the filters.


RESULTS
When assessed by individual Marple stage, there was significantly greater airborne endotoxin concentration (endotoxin units per cubic meter) in the size fraction >9.8 μm for the FH operations whereas at the size fraction 1.6-3.5 μm, the CH operations had significantly greater airborne endotoxin concentration than the FH operations. Endotoxin concentration in the dust mass (endotoxin units per milligram) was significantly greater in the CH operations as compared to the FH operations for all size fractions >1.6 μm. As such, endotoxin in the respirable fraction accounted for 24% of the total endotoxin in the CH operations whereas it accounted for only 11% in the FH operations. There was significantly more dust in all size fractions in the FH operations as compared to the CH poultry operations.


CONCLUSIONS
There is more endotoxin in the presence of significantly lower dust levels in the respirable particle size fractions in CH poultry operations as compared to the FH poultry operations. This difference in respirable endotoxin may be important in relation to the differential respiratory response experienced by CH and FH poultry operation workers.
Kirychuk
Shelley P
SP
University of Saskatchewan, Saskatoon, Canada. shelley.kirychuk@usask.ca
Reynolds
Stephen J
SJ
Koehncke
Niels K
NK
Lawson
Joshua
J
Willson
Philip
P
Senthilselvan
Ambikaipakan
A
Marciniuk
Darcy
D
Classen
Henry L
HL
Crowe
Trever
T
Just
Natasha
N
Schneberger
David
D
Dosman
James A
JA
D000395:Air Pollutants, Occupational / Q000032:analysis* / Q000633:toxicity; D000822:Animal Husbandry; D000818:Animals; D002908:Chronic Disease; D004391:Dust / Q000032:analysis*; D004731:Endotoxins / Q000032:analysis* / Q000633:toxicity; D004784:Environmental Monitoring / Q000379:methods; D005374:Filtration / Q000295:instrumentation; D006799:Housing, Animal; D006801:Humans; D019570:Inhalation Exposure / Q000032:analysis*; D008033:Limulus Test; D016273:Occupational Exposure / Q000032:analysis*; D010316:Particle Size; D011200:Poultry; D012120:Respiration Disorders / Q000209:etiology; D012525:Saskatchewan; D013183:Sputum
D000395:Air Pollutants, Occupational; D004391:Dust; D004731:Endotoxins