Mechanistic modelling for ecotoxicology and ecology

DEBtox Researc

Welcome to DEBtox Research

DEBtox Research is the private company that I (Tjalling Jager) operate since January 2015 to offer my knowledge and expertise on mechanistic modelling to customers. My mission is to strengthen the scientific foundation of ecotoxicology, environmental risk assessment, and life-history ecology, by the application of mechanistic models. Mechanistic modelling attempts to provide a (simplistic) explanation for the observed behaviour of the organism, rather than just describing it. Thereby, we gain a deeper understanding of the organism and the stressors affecting it. In turn, this understanding can help us to make educated extrapolations to untested situations. This is where fundamental research meets application!

My specialty is in the development and application of toxicokinetic and toxicodynamic models (at the level of the individual), in particular, models based on Dynamic Energy Budget (DEB) theory (more specifically: DEBkiss and DEBtox) and the General Unified Threshold model for Survival (GUTS). These models can be applied to a wide range of species (in principle: all), and an enormous range of fundamental and applied research questions. More information on the type of activities that I have to offer can be found on the activities page.

I also maintain the sites and which contain much more detailed information about these models, as well as links to free e-books, software, and lists of relevant publications. This website is dedicated to my project activities.


  • 4 July 2022: Take a look at the DeEP tool for EPx predictions with DEBtox2019. Note that this tool does not perform calibrations or validations on data sets, but rather makes EPx predictions for exposure profiles, such as those from FOCUS.
  • The website for the 2023 DEB school and symposium can be found here.
  • The Autumn course Dynamic Modelling of Toxic effects has finished. We might run one again in 2023. See the course page for details.
  • 25 February 2021: version 1.1 of the standalone of openGUTS is available for download. This version corrects an error and adds some new batch functionality. See openGUTS download page. Version 1.0 of this software was developed in a Cefic-LRI funded project.

DEBtox Research,, Chamber of Commerce Utrecht 62405055, email: tjalling (at)