Particles causing lung disease
The lung has a limited number of patterns of reaction to inhaled particles. The disease observed depends upon the location: conducting airways, terminal bronchioles and alveoli, and upon the nature of inflammation induced: acute, subacute or chronic. Many different agents cause narrowing of conducting airways (asthma) and some of these cause permanent distortion or obliteration of airways as well. Terminal bronchioles appear to be particularly susceptible to particles which cause goblet cell metaplasia, mucous plugging and ultimately peribronchiolar fibrosis. Cancer is the last outcome at the bronchial level and appears to depend upon continuous exposure to or retention of an agent in the airway and failure of the affected cells to be exfoliated which may be due to squamous metaplasia. Alveoli are populated by endothelial cells, Type I or pavement epithelial cells and metabolically active cuboidal Type II cells that produce the lungs specific surfactant, dipalmytol lecithin. Disturbances of surfactant lead to edema in distal lung while laryngeal edema due to anaphylaxis or fumes may produce asphyxia. Physical retention of indigestible particles or retention by immune memory responses may provoke hyaline membranes, stimulate alveolar lipoproteinosis and finally fibrosis. This later exuberant deposition of connective tissue has been best studied in the occupational pneumoconioses especially silicosis and asbestosis. In contrast emphysema a catabolic response appears frequently to result from leakage or release of lysosomal proteases into the lung during processing of cigarette smoke particles. 164 references, 1 figure, 2 tables.
- Research Organization:
- Univ. of Southern California School of Medicine, Los Angeles
- OSTI ID:
- 5516779
- Journal Information:
- Environ. Health Perspect.; (United States), Vol. 55
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
LUNGS
NEOPLASMS
PATHOLOGICAL CHANGES
PARTICULATES
HEALTH HAZARDS
ASBESTOS
ASTHMA
BIOLOGICAL PATHWAYS
FIBROSIS
INFLAMMATION
INHALATION
PNEUMOCONIOSES
RESPIRATORY SYSTEM DISEASES
RETENTION
REVIEWS
SILICA
TOBACCO SMOKES
AEROSOLS
BODY
CHALCOGENIDES
COLLOIDS
DISEASES
DISPERSIONS
DOCUMENT TYPES
HAZARDS
INTAKE
MINERALS
ORGANS
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
PARTICLES
RESIDUES
RESPIRATORY SYSTEM
SILICON COMPOUNDS
SILICON OXIDES
SMOKES
SOLS
SYMPTOMS
560306* - Chemicals Metabolism & Toxicology- Man- (-1987)