GUTS Shiny Application



This web page allows interactive simulations of the General Unified Threshold model of Survival (GUTS) based on the scaled internal concentration either with a constant or a time-variable exposure concentration profile. The two reduced (RED) versions are implemented: the stochastic death version (GUTS-RED-SD) and the individual tolerance version (GUTS-RED-IT). See [1 , 2] for details.


All calculations can be run directly within the R software by using package morse; a tutorial is available here.

Contact: sandrine.charles@univ-lyon1.fr


Input your concentration profile


Please upload at least a two-column file in .txt or .csv format. The correct separator has to be chosen. Columns with headers must be the followings:

  • The time points at which you measured concentrations (header = 'time')
  • The measured concentrations within the organisms, must be in μg.g-1 (header = 'conc'). In case of constant exposure, the second column must be filled-in with the same value whatever the time point.

Model and parameters

Choose one or both models




Parameter values











Be careful, with distributed parameters, calculations may be long. Be patient!

Parameter values









Be careful, with distributed parameters, calculations may be long. Be patient!

Parameter values






Validation

Prediction of the number of survivors over time and comparison with observed data

Please provide a file with a column 'Nsurv' and a column 'time', corresponding to your observed data.


Click this button each time you update a setting above
Calculations can take a long time, be patient!


EFSA validation criteria [ 3 ].

Percentage of PPC is:
Percentage of NRMSE is:
Percentage of SPPE is:



Margin of Safety

The concept of 'margin-of-safety' corresponds to the concept of 'x% Lethal Profile' or LPx as emphasized by the recent Scientific Opinion from EFSA [ 3 ].






Click this button each time you update a setting above
Calculations can take a long time, be patient!

Prediction of SOT

Prediction of the Survival rate Over Time (SOT)



Downloads


References

[1] Jager T, Albert C, Preuss T, Ashauer R (2011). General Unified Threshold Model of Survival-a Toxicokinetic-Toxicodynamic Framework for Ecotoxicology. Environnemental Science and Technology. https://doi.org/10.1021/es103092a .
[2] Ashauer R et al. (2016). Modelling survival: exposure pattern, species sensitivity and uncertainty. Scientific Reports. https://doi.org/10.1038/srep29178.
[3] EFSA PPR Panel (2018). Scientific Opinion on the state of the art of Toxicokinetic/Toxicodynamic (TKTD) effect models for regulatory risk assessment of pesticides for aquatic organisms. EFSA Journal. https://www.efsa.europa.eu/en/efsajournal/pub/5377.
[4] Nyman A-M, Schirmer K, Ashauer R (2012). Toxicokinetic-toxicodynamic modelling of survival of Gammarus pulex in multiple pulse exposures to propiconazole: model assumptions, calibration data requirements and predictive power. Ecotoxicology. https://doi.org/10.1007/s10646-012-0917-0.
[5] Baudrot V, Veber P, Gence G, Charles S. (2018). Fit Reduced GUTS Models Online: From Theory to Practice. Integrated Environmental Assessment and Management. https://doi.org/10.1002/ieam.4061.

Staff and Contributors

Sandrine Charles, Professor at University Lyon 1
Virgile Baudrot, Scientific Researcher
Aurélie Siberchicot, Engineer at University Lyon 1
Maud Repellin, bachelor student at University Lyon 1