Current limitations in the methodology for enumeration and identification of airborne bacteria compromise the precision and accuracy of bioaerosol exposure assessment.
In this study, flow cytometry and fluorescent in situ hybridization (FISH) were evaluated for the assessment of exposures to airborne bacteria.
Laboratory-generated two-component bioaerosols in exposure chambers and complex native bioaerosols in swine barns were sampled with two types of liquid impingers (all-glass impinger-30 and May 3-stage impinger).
Aliquots of collection media were processed and enumerated by a standard culture technique, microscopy, or flow cytometry after nucleic acid staining with 4'6-diamidino-2-phenylindole (DAPI) and identified taxonomically by FISH.
DAPI-labeled impinger samples yielded comparable estimates of bioaerosol concentrations when enumerated by microscopy or flow cytometry.
The standard culture method underestimated bioaerosol concentrations by 2 orders of magnitude when compared to microscopy or flow cytometry.
In the FISH method, aliquots of collection media were incubated with a probe universally complementary to eubacteria, a probe specific for several Pseudomonas species, and a probe complementary to eubacteria for detection of nonspecific binding.
With these probes, FISH allowed quantitative identification of Pseudomonas aeruginosa and Escherichia coli hioaerosols in the exposure chamber without measurable nonspecific binding. (...)
Mots-clés Pascal : Pseudomonas aeruginosa, Pseudomonadaceae, Pseudomonadales, Bactérie, Escherichia coli, Enterobacteriaceae, Poussière, Porcherie, Enumération, Identification, In situ, Exposition professionnelle, Hybridation moléculaire, Cytométrie flux, Méthode, Aérosol, Bioaérosol
Mots-clés Pascal anglais : Pseudomonas aeruginosa, Pseudomonadaceae, Pseudomonadales, Bacteria, Escherichia coli, Enterobacteriaceae, Dust, Pig barn, Enumeration, Identification, In situ, Occupational exposure, Molecular hybridization, Flow cytometry, Method, Aerosols
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 97-0304130
Code Inist : 002A05B14. Création : 15/07/1997.