External Review of the Concentration x Time (ten Berge) Model (2008)
Abstract
This report is intended to provide an overview of beta version 1.0 of the implementation of a concentration-time (CxT) model originally programmed and provided by Wil ten Berge (referred to hereafter as the ten Berge model). The recoding and development described here represent the first steps towards integration of the ten Berge model into the EPA benchmark dose software (BMDS). At present the software can be run from a Windows Command Prompt; at a later date it will be possible to invoke the ten Berge model from the beta interface for BMDS version 2.0.
CxT modeling has a long history of use in the assessment of acute exposure risks. CxT modeling is used primarily in the context of short-term exposures where both the concentration and the duration of exposure are considered important and relevant for estimating risk. Haber’s Law, which states that risk is related to CxT has been a motivation for development of CxT models, although such models (including the current implementation) have generalized the simple CxT relationships somewhat. Thus, the software under consideration here is intended to be applied to data that presents both concentration (or dose) values and durations of exposure (the time component, typically shorter-term exposure durations), as well as responses (dichotomous response rates) to estimate a concentration-time-response relationship.
Impact/Purpose
CxT modeling has a long history of use in the assessment of acute exposure risks. CxT modeling is used primarily in the context of short-term exposures where both the concentration and the duration of exposure are considered important and relevant for estimating risk. Haber’s Law, which states that risk is related to CxT has been a motivation for development of CxT models, although such models (including the current implementation) have generalized the simple CxT relationships somewhat. Thus, the software under consideration here is intended to be applied to data that presents both concentration (or dose) values and durations of exposure (the time component, typically shorter-term exposure durations), as well as responses (dichotomous response rates) to estimate a concentration-time-response relationship.
Citation
U.S. EPA. Benchmark Dose Software Development And Maintenance ten Berge Cxt Models. U.S. Environmental Protection Agency, Washington, DC, 2008.
Downloads
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