title: Biological activities of respirable dust from Eastern Canadian peat moss factories.
abstract: Bacteria, moulds, endotoxin and quartz from respirable dust of agricultural and industrial buildings are typically incriminated for the respiratory health decline of exposed workers despite that dust being an undefined mixture and quantification methods of aerosolized bacteria, moulds or endotoxin not being standardized yet. We developed an in vitro alveolar epithelial cell system in which biological activities of peat moss factories' dust might be correlated to bacteria, mould, endotoxin and quartz concentrations of the analyzed samples. Following exposure, interleukin-8 protein secretion, necrosis and apoptosis of the exposed A549 cells were monitored respectively with ELISA on cell supernatants, trypan blue exclusion and DNA fragmentation detection by flow cytometry. Respirable dust was collected with liquid impingers and respirable quartz with 10mm Dorr-Oliver cyclones. We quantified mesophilic bacteria, mesophilic moulds and endotoxins from liquid impinger samples. No correlation was observed between biological activities of dust and bacteria, mould, endotoxin or quartz concentrations under our experimental conditions. Our speculation is that simple measurements, such as dust concentrations, may not be adequate indicators of the human respiratory health hazard for a given environment.
authors.affiliation: Institut universitaire de cardiologie et de pneumologie de Québec (Hôpital Laval), 2725 chemin Sainte-Foy, Québec, Canada G1V 4G5. valerie.letourneau@criucpq.ulaval.ca
authors.forename: Valérie
authors.initials: V
authors.lastname: Létourneau
authors.forename: Anne
authors.initials: A
authors.lastname: Mériaux
authors.forename: Nicole
authors.initials: N
authors.lastname: Goyer
authors.forename: Jamila
authors.initials: J
authors.lastname: Chakir
authors.forename: Yvon
authors.initials: Y
authors.lastname: Cormier
authors.forename: Caroline
authors.initials: C
authors.lastname: Duchaine
mesh_terms: D000391:Air Microbiology; D000395:Air Pollutants, Occupational / Q000032:analysis / Q000633:toxicity*; D001419:Bacteria / Q000302:isolation & purification; D002170:Canada; D002460:Cell Line; D015169:Colony Count, Microbial; D004391:Dust / Q000032:analysis*; D004731:Endotoxins / Q000032:analysis / Q000633:toxicity; D004784:Environmental Monitoring; D005658:Fungi / Q000145:classification / Q000302:isolation & purification; D006801:Humans; D019570:Inhalation Exposure / Q000032:analysis; D016273:Occupational Exposure / Q000032:analysis; D011791:Quartz / Q000032:analysis; D020545:Respiratory Mucosa / Q000187:drug effects; D044003:Sphagnopsida; D013172:Spores, Fungal; D018675:Toxicity Tests / Q000379:methods
chemical_list: D000395:Air Pollutants, Occupational; D004391:Dust; D004731:Endotoxins; D011791:Quartz