A Biomathematical Model of Particle Clearance and Retention in the Lungs of Coal Miners. I. Model Development

Details

• Personal Author:
  Green FHY ; Kuempel, Eileen D. ; O'Flaherty EJ ; Smith RJ ; Stayner, Leslie T. ; Vallyathan V
• Description:
  To understand better the factors influencing the relationships among airborne particle exposure, lung burden, and fibrotic lung disease, we developed a biologically based kinetic model to predict the long-term retention of particles in the lungs of coal miners. This model includes alveolar, interstitial, and hilar lymph node compartments. The 131 miners in this study had worked in the Beckley, West Virginia, area and died during the 1960s. The data used to develop this model include exposure to respirable coal mine dust by intensity and duration within each job, lung and lymph node dust burdens at autopsy, pathological classification of fibrotic lung disease, and smoking history. Initial parameter estimates for this model were based on both human and animal data of particle deposition and clearance and on the biological and physical factors influencing these processes. Parameter estimation and model fit to the data were determined using least squares. Results show that the end-of-life lung dust burdens in these coal miners were substantially higher than expected from first-order clearance kinetics, yet lower than expected from the overloading of alveolar clearance predicted from rodent studies. The best-fitting and most parsimonious model includes processes for first-order alveolar-macrophage-mediated clearance and transfer of particles to the lung interstitium. These results are consistent with the particle retention patterns observed previously in the lungs of primates. The findings indicate that rodent models extrapolated to humans, without adjustment for the kinetic differences in particle clearance and retention, would be inadequate for predicting lung dust burdens in humans. Also, this human lung kinetic model predicts greater retained lung dust burdens from occupational exposure than predicted from current human models based on lower exposure data. This model is useful for risk assessment of particle-induced lung diseases, by estimating equivalent internal doses in rodents and humans and predicting lung burdens in humans with occupational dust exposures. [Description provided by NIOSH]
• Subjects:
  Air Pollutants, Occupational Coal Coal Mining Dust Lung Lung Diseases Mining Occupational Exposure Occupational Health Particulate Matter Respiratory System Respiratory Tract Diseases Risk Assessment Risk Factors Safety

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• Keywords:
  Airborne-particles Coal-dust Coal-miners Coal-mining Dust-exposure Dust-particles Dusts Lung-burden Lung-disease Mathematical-models Miners Mining-industry Models Occupational-exposure Pulmonary-system-disorders Respirable-dust Respiratory-system-disorders Risk-analysis Risk-factors

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• ISSN:
  0273-2300
• Document Type:
  Text
• Genre:
  Journal Article
• Place as Subject:
  Ohio ; OSHA Region 3 ; OSHA Region 5 ; West Virginia
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  EID - Education and Information Division ; HELD - Health Effects Laboratory Division
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  69-87
• Volume:
  34
• Issue:
  1
• NIOSHTIC Number:
  nn:20021779
• Citation:
  Regul Toxicol Pharmacol 2001 Aug; 34(1):69-87
• Federal Fiscal Year:
  2001
• Peer Reviewed:
  True
• Source Full Name:
  Regulatory Toxicology and Pharmacology
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:b9de3bc0fc55bf211beae3a70a87e3326eb9bb5843f38014b3e07f79cb8ec8e1c4773cdb227e9a4aac5959f1917983fdeaa939d84bf8ee34e356e9aea1e9aacb
• Download URL:
  https://stacks.cdc.gov/view/cdc/198886/cdc_198886_DS1.pdf
• File Type:
  [PDF - 168.61 KB ]