title: Persistent effects of chlorine inhalation on respiratory health.
abstract: Chlorine gas is a toxic respiratory irritant that is considered a chemical threat agent because of the potential for release in industrial accidents or terrorist attacks. Chlorine inhalation damages the respiratory tract, including the airways and distal lung, and can result in acute lung injury. Some individuals exposed to chlorine experience a full recovery from acute injury, whereas others develop persistent adverse effects, such as respiratory symptoms, inflammation, and lung-function decrements. In animal models, chlorine can produce persistent inflammation, remodeling, and obstruction in large or small airways, depending on species. Airways with pseudostratified epithelia are repaired efficiently, with surviving basal epithelial cells serving as progenitor cells that repopulate the complement of differentiated cell types. Distal airways lacking basal cells are repaired less efficiently, leading to chronic inflammation and fibrosis at these sites. Persistent chlorine-induced airway disease in humans is treated with asthma medication to relieve symptoms. However, such treatment does not ameliorate the underlying disease pathogenesis, so treatments that are more effective at preventing initial development of airway disease after irritant gas exposure and at reversing established disease are needed.
authors.affiliation: Department of Environmental and Occupational Health Sciences, School of Public Health and Information Sciences, University of Louisville, Louisville, Kentucky. Gary.Hoyle@louisville.edu.
authors.forename: Gary W
authors.initials: GW
authors.lastname: Hoyle
authors.affiliation: Division of Environmental Health, Department of Public Health Services, Medical University of South Carolina, Charleston, South Carolina.
authors.forename: Erik R
authors.initials: ER
authors.lastname: Svendsen
mesh_terms: D055371:Acute Lung Injury / Q000139:chemically induced / Q000453:epidemiology / Q000628:therapy; D000818:Animals; D001993:Bronchodilator Agents / Q000494:pharmacology / Q000627:therapeutic use; D002713:Chlorine / Q000008:administration & dosage* / Q000633:toxicity*; D006304:Health Status; D006801:Humans; D019570:Inhalation Exposure / Q000009:adverse effects*; D012120:Respiration Disorders / Q000139:chemically induced* / Q000453:epidemiology* / Q000628:therapy; D015656:Respiratory Mechanics / Q000187:drug effects* / Q000502:physiology; D020545:Respiratory Mucosa / Q000187:drug effects / Q000502:physiology; D013997:Time Factors
chemical_list: D001993:Bronchodilator Agents; D002713:Chlorine
keywords: bronchiolitis obliterans; chemical threat agent; chlorine; small airway disease