Characterization of inhalable endotoxin, glucan, and dust exposures in Iowa farmers.
Int J Hyg Environ Health
; 228: 113525, 2020 07.
Article
in En
| MEDLINE
| ID: mdl-32311660
ABSTRACT
BACKGROUND:
The observed deficit of lung cancer in farmers has been partly attributed to exposure to organic dusts and endotoxins based largely on surrogate metrics. To move beyond these surrogates for etiological studies, we characterized task-based and time-weighted average (TWA) exposure to inhalable endotoxin, (1 â 3)-ß-D-glucan, and dust in Iowa farmers.METHODS:
We collected 320 personal inhalable dust samples from 32 farmers during 69 sample days in 2015 and 2016. Samples were collected using Button aerosol samplers and analyzed for endotoxin using a kinetic chromogenic amebocyte lysate assay, and for (1 â 3)-ß-D-glucan using a Limulus endpoint assay. We assessed relationships between bioaerosol concentrations and selected tasks and farm characteristics using linear mixed-effects models.RESULTS:
Bedding work, hog handling, and working in barn/confinement buildings, grain bins, and grain elevators were associated with higher endotoxin exposure. We found a monotonic trend between higher endotoxin concentrations and increasing number of animals. Bedding work, cleaning, and feed/grain storage work were associated with higher (1 â 3)-ß-D-glucan concentrations. The median concentrations by task spanned one order of magnitude for inhalable dust and two orders of magnitude for endotoxin and (1 â 3)-ß-D-glucan. Pearson correlations between endotoxin and glucan concentrations were 0.22 for TWA exposure and 0.56 for task samples.CONCLUSIONS:
This characterization of exposure factors that influence bioaerosol concentrations can support the development of refined bioaerosol exposure metrics for future etiologic analyses of cancer and other health outcomes in farmers.Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Occupational Exposure
/
Inhalation Exposure
/
Air Pollutants, Occupational
/
Dust
/
Endotoxins
/
Farmers
/
Glucans
Type of study:
Prognostic_studies
Limits:
Aged
/
Humans
/
Male
Country/Region as subject:
America do norte
Language:
En
Journal:
Int J Hyg Environ Health
Journal subject:
SAUDE AMBIENTAL
/
SAUDE PUBLICA
Year:
2020
Document type:
Article
Affiliation country:
United States