title: Characterization of toxicokinetics and toxicodynamics with linear systems theory: application to lead-associated cognitive decline.
abstract: We present a theoretical approach to analysis of toxicokinetics and toxicodynamics using linear systems theory. In our approach, we define two impulse response functions that characterize the kinetic behavior of an environmental agent in the body and the dynamic time-course behavior of its effect on the body. This approach provides a formalism for understanding the relation among exposure, dose, and cumulative biologically effective dose and for understanding the implications of an effect time-course on cross-sectional and longitudinal data analyses. We use lead-associated cognitive decline as a specific example where the approach may be applied.
authors.affiliation: Department of Environmental Health Sciences, The Johns Hopkins School of Hygiene and Public Health, Baltimore, Maryland 21205-2179, USA. jlinks@jhsph.edu
authors.forename: J M
authors.initials: JM
authors.lastname: Links
authors.forename: B S
authors.initials: BS
authors.lastname: Schwartz
authors.forename: D
authors.initials: D
authors.lastname: Simon
authors.forename: K
authors.initials: K
authors.lastname: Bandeen-Roche
authors.forename: W F
authors.initials: WF
authors.lastname: Stewart
mesh_terms: D003072:Cognition Disorders / Q000139:chemically induced* / Q000453:epidemiology; D003430:Cross-Sectional Studies; D004785:Environmental Pollutants / Q000009:adverse effects*; D006801:Humans; D007700:Kinetics; D007854:Lead / Q000009:adverse effects*; D016014:Linear Models; D008137:Longitudinal Studies; D008962:Models, Theoretical
chemical_list: D004785:Environmental Pollutants; D007854:Lead