Schematic representation of a dynamic energy budget model

Of course, the acceptable level of model complexity is closely related to the level of detail of the experimental data. Energy budget approaches are generally most informative when data on body size and reproductive output are available over time for a considerable part of the life cycle. Examples of the application of DEB theory to life cycle toxicity data for single compounds can be found in Jager et al. (2004), Alda Alvarez et al. (2005), and Pieters et al. (2006). More complicated TD approaches require other types of experimental data (e.g., at the molecular level), but should never ignore the level of resource allocation when endpoints such as growth and reproduction are concerned. 

The DEB theory is also applicable to birds and mammals (Kooijman 2000), but has not been applied extensively to toxic effects here yet (because human toxicology is concerned with more specific effects than disturbance of resource allocation). However, the paper of Van Leeuwen et al. (2003) on tumor growth shows the potential of DEB approaches in this area. 

1 Toxicodynamic Studies of Chemical Mixtures Using Physiologically or Biologically Based Modeling 

7 Toxicodynamic Modeling of Noncancer Effects of Chemical Mixtures 

The second case study involved PBTD modeling of toxicodynamic interactions between trichloroethylene (TCE) and 1,1-dichloroethylene (DCE) regarding their binding and depletion of hepatic glutathione (GSH) in relation to the intrinsic hepatic GSFI synthesis (El-Masri et al. 1996b), which is a protective mechanism 

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Figure 2.11 Schematic representation of a dynamic energy budget model. Numbers represent some of the positions where toxicants may affect resource allocation. (Adapted from Kooijman and Bedaux 1996.)...

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