title: Lung toxicity in mice of airborne particulate matter from a modern layer hen facility containing Proposition 2-compliant animal caging.
abstract: Proposition 2, which requires that egg-laying hens be confined only in ways that allow these animals to lie down, stand up, fully extend their limbs and turn around freely, was passed by the voters of California in 2008. These new housing requirements were introduced in the USA and European Union without considering the potential impact of changes in layer hen housing on the health of poultry workers in the new facilities. Particles were collected from ambient air inside a large layer hen complex featuring separate barns with conventional battery caging, enriched caging, or 'free range' (aviary) housing during winter, spring, and summer seasons over one year. Toxicity of the particles was evaluated by analysis of inflammatory cell influx into lung lavage fluid after intratracheal instillation into mice. Capacity of the particles to elicit oxidative stress was evaluated using a macrophage cell line engineered with a reporter gene sensitive to nuclear factor κB activation. We observed similar pro-inflammatory and pro-oxidant effects of the particles collected from different types of barns and over different seasons, suggesting that standard industrial hygiene techniques for evaluating respirable particles in ambient air can adequately monitor worker risk. Based on particle concentrations found in ambient air in the barns, we can rank the facilities for worker exposure to particles as conventional caging (now banned) approximately equal to enriched caging (permitted under Proposition 2). Aviary housing is associated with increased exposure of workers to particulate matter and, therefore, to greater risk of allergic reactions and/or decreased respiratory function.
authors.affiliation: Department of Internal Medicine, Division of Pulmonary, Critical Care, and Sleep Medicine, School of Medicine, University of California, Davis, CA, USA.
authors.forename: Lisa M
authors.initials: LM
authors.lastname: Franzi
authors.affiliation: Department of Internal Medicine, Division of Pulmonary, Critical Care, and Sleep Medicine, School of Medicine, University of California, Davis, CA, USA.
authors.forename: Angela L
authors.initials: AL
authors.lastname: Linderholm
authors.affiliation: Department of Internal Medicine, Division of Pulmonary, Critical Care, and Sleep Medicine, School of Medicine, University of California, Davis, CA, USA.
authors.forename: Michelle
authors.initials: M
authors.lastname: Rabowsky
authors.affiliation: Department of Internal Medicine, Division of Pulmonary, Critical Care, and Sleep Medicine, School of Medicine, University of California, Davis, CA, USA.
authors.forename: Jerold A
authors.initials: JA
authors.lastname: Last
mesh_terms: D000395:Air Pollutants, Occupational / Q000633:toxicity*; D000822:Animal Husbandry; D000818:Animals; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry / Q000276:immunology; D002140:California; D002460:Cell Line; D002645:Chickens; D004731:Endotoxins / Q000737:chemistry / Q000633:toxicity; D006799:Housing, Animal / Q000331:legislation & jurisprudence / Q000592:standards; D006801:Humans; D019570:Inhalation Exposure / Q000009:adverse effects; D008168:Lung / Q000187:drug effects* / Q000276:immunology; D016676:Macrophages, Alveolar / Q000187:drug effects / Q000276:immunology; D008297:Male; D008807:Mice, Inbred BALB C; D016328:NF-kappa B / Q000819:agonists / Q000378:metabolism; D016273:Occupational Exposure / Q000009:adverse effects; D018384:Oxidative Stress / Q000187:drug effects; D052638:Particulate Matter / Q000633:toxicity*; D020545:Respiratory Mucosa / Q000187:drug effects* / Q000276:immunology; D012621:Seasons; D023382:Toxicity Tests, Acute; D000078329:Workforce
chemical_list: D000395:Air Pollutants, Occupational; D004731:Endotoxins; D016328:NF-kappa B; D052638:Particulate Matter
keywords: Occupational health; egg production; endotoxin; lung inflammation; macrophages; oxidative stress