title: Identification of mycobacteria in peat moss processing plants: application of molecular biology approaches.
abstract: Peat moss processing plant workers are exposed to high concentrations of bioaerosols. Although mycobacteria have been cultured from peat moss, no study has examined the workers' exposure to mycobacterial bioaerosols. We evaluated the presence of mycobacteria in air samples from peat moss processing plants using molecular biology approaches (cloning-sequencing and polymerase chain reaction (PCR)) and the workers exposure using immunoglobulin G (IgG) complexes to mycobacteria. In addition, species detected in air samples and in peat moss were compared. Two peat moss processing plants were chosen among 14 previously studied. A total of 49 clones were sequenced. Real-time PCR was also performed on the same air samples to evaluate the airborne concentration of mycobacteria and estimate exposure levels. Several Mycobacterium species were present in the air samples (M. malmoense, M. smegmatis, M. graceum, M. bohemicum, and M. interjectum). Mycobacterium avium was recovered by culture in peat moss but not in the air using the molecular approach. Total airborne Mycobacterium concentration was estimated at 8.2 x 10(8)/m3. Workers had IgG against the mycobacterial mix and M. avium, suggesting significant exposure. The findings from air samples, supported by IgG measurements, demonstrate that peat moss processing plant workers are exposed to mycobacteria in addition to other biological agents.
authors.affiliation: Centre de recherche, Hôpital Laval, Institut Universitaire de pneumologie et de cardiologie de l'Université Laval, Québec, QC, Canada.
authors.forename: Marie-Pierre
authors.initials: MP
authors.lastname: Cayer
authors.forename: Marc
authors.initials: M
authors.lastname: Veillette
authors.forename: Pascal
authors.initials: P
authors.lastname: Pageau
authors.forename: Richard
authors.initials: R
authors.lastname: Hamelin
authors.forename: Marie-Josée
authors.initials: MJ
authors.lastname: Bergeron
authors.forename: Anne
authors.initials: A
authors.lastname: Mériaux
authors.forename: Yvon
authors.initials: Y
authors.lastname: Cormier
authors.forename: Caroline
authors.initials: C
authors.lastname: Duchaine
mesh_terms: D000336:Aerosols; D000382:Agricultural Workers' Diseases / Q000382:microbiology*; D000395:Air Pollutants, Occupational / Q000032:analysis*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D009162:Mycobacterium avium / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification*; D009170:Nontuberculous Mycobacteria / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification*; D012336:RNA, Ribosomal, 16S / Q000302:isolation & purification*; D044003:Sphagnopsida / Q000382:microbiology*
chemical_list: D000336:Aerosols; D000395:Air Pollutants, Occupational; D007074:Immunoglobulin G; D012336:RNA, Ribosomal, 16S