Modelling of individual subject ozone exposure response kinetics

Edward S Schelegle, William C. Adams, William F. Walby, M. Susan Marion

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

Context: A better understanding of individual subject ozone (O3) exposure response kinetics will provide insight into how to improve models used in the risk assessment of ambient ozone exposure. Objective: To develop a simple two compartment exposureresponse model that describes individual subject decrements in forced expiratory volume in one second (FEV1) induced by the acute inhalation of O3 lasting up to 8 h. Methods: FEV 1 measurements of 220 subjects who participated in 14 previously completed studies were fit to the model using both particle swarm and nonlinear least squares optimization techniques to identify three subject-specific coefficients producing minimum "global" and local errors, respectively. Observed and predicted decrements in FEV1 of the 220 subjects were used for validation of the model. Further validation was provided by comparing the observed O3-induced FEV1 decrements in an additional eight studies with predicted values obtained using model coefficients estimated from the 220 subjects used in cross validation. Results: Overall the individual subject measured and modeled FEV1 decrements were highly correlated (mean R2 of 0.69 ± 0.24). In addition, it was shown that a matrix of individual subject model coefficients can be used to predict the mean and variance of group decrements in FEV1. Conclusion: This modeling approach provides insight into individual subject O3 exposure response kinetics and provides a potential starting point for improving the risk assessment of environmental O3 exposure.

Original languageEnglish (US)
Pages (from-to)401-415
Number of pages15
JournalInhalation Toxicology
Volume24
Issue number7
DOIs
StatePublished - Jun 2012

Fingerprint

Ozone
Kinetics
Environmental Exposure
Forced Expiratory Volume
Least-Squares Analysis
Inhalation
Risk assessment

Keywords

  • Exposureresponse model
  • Human
  • Ozone

ASJC Scopus subject areas

  • Toxicology
  • Health, Toxicology and Mutagenesis

Cite this

Modelling of individual subject ozone exposure response kinetics. / Schelegle, Edward S; Adams, William C.; Walby, William F.; Marion, M. Susan.

In: Inhalation Toxicology, Vol. 24, No. 7, 06.2012, p. 401-415.

Research output: Contribution to journalArticle

Schelegle, Edward S ; Adams, William C. ; Walby, William F. ; Marion, M. Susan. / Modelling of individual subject ozone exposure response kinetics. In: Inhalation Toxicology. 2012 ; Vol. 24, No. 7. pp. 401-415.
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