title: Conceptual model for assessment of inhalation exposure: defining modifying factors.
abstract: The present paper proposes a source-receptor model to schematically describe inhalation exposure to help understand the complex processes leading to inhalation of hazardous substances. The model considers a stepwise transfer of a contaminant from the source to the receptor. The conceptual model is constructed using three components, i.e. (i) the source, (ii) various transmission compartments and (iii) the receptor, and describes the contaminant's emission and its pattern of transport. Based on this conceptual model, a list of nine mutually independent principal modifying factors (MFs) is proposed: activity emission potential, substance emission potential, localized control, separation, segregation, dilution, worker behavior, surface contamination and respiratory protection. These MFs describe the exposure process at a high level of abstraction so that the model can be generically applicable. A list of exposure determinants underlying each of these principal MFs is proposed to describe the exposure process at a more detailed level. The presented conceptual model is developed in conjunction with an activity taxonomy as described in a separate paper. The proposed conceptual model and MFs should be seen as 'building blocks' for development of higher tier exposure models.
authors.affiliation: Business Unit Quality and Safety, Department of Food and Chemical Risk Analysis, TNO Quality of Life, PO Box 360, 3700 AJ Zeist, The Netherlands. erik.tielemans@tno.nl
authors.forename: Erik
authors.initials: E
authors.lastname: Tielemans
authors.forename: Thomas
authors.initials: T
authors.lastname: Schneider
authors.forename: Henk
authors.initials: H
authors.lastname: Goede
authors.forename: Martin
authors.initials: M
authors.lastname: Tischer
authors.forename: Nick
authors.initials: N
authors.lastname: Warren
authors.forename: Hans
authors.initials: H
authors.lastname: Kromhout
authors.forename: Martie
authors.initials: M
authors.lastname: Van Tongeren
authors.forename: Joop
authors.initials: J
authors.lastname: Van Hemmen
authors.forename: John W
authors.initials: JW
authors.lastname: Cherrie
mesh_terms: D000395:Air Pollutants, Occupational / Q000032:analysis*; D000465:Algorithms; D004784:Environmental Monitoring / Q000379:methods*; D015386:Hazardous Substances / Q000032:analysis; D006801:Humans; D019570:Inhalation Exposure / Q000032:analysis*; D008954:Models, Biological; D016273:Occupational Exposure / Q000032:analysis
chemical_list: D000395:Air Pollutants, Occupational; D015386:Hazardous Substances