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 a two-column file in text format. Default is comma-separated values but other separators can be chosen. Columns with headers must be the followings:
1. The time points at which you measured concentrations (header = 'time');
2. The measured concentrations (header = 'conc').
In case of constant exposure, the second column must be filled-in with the same value whatever the time point.

Here are six example files to test the GUTS-ShinyApp:
conc-cst.csv
conc-var-01.csv
conc-var-02.csv
FOCUS-SW.csv
conc-ringtest-B-varA.txt
conc-ringtest-B-varB.txt

Model and parameters

Choose one or both models




Parameter values










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

Parameter values

The file that contains the distributed parameters must be with 4 columns named "hb", "kd", "zw" and "bw", with a tab as separator and a dot for decimals.
Such a file may come from a fit with the R package morse or have been saved after running MOSAIC_GUTS-fit [ 5 ].
Here is an example file for your convenience: mcmc-ringtest-B-SD.txt







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

Parameter values

The file that contains the distributed parameters must be with 4 columns named "hb", "kd", "mw" and "beta", with a tab as separator and a dot for decimals.
Such a file may come from a fit with the R package morse or have been saved after running MOSAIC_GUTS-fit. [ 5 ].
Here is an example file for your convenience: mcmc-ringtest-B-IT.txt




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.

Here are two example files:
Nsurv-ringtest-B-varA.txt
Nsurv-ringtest-B-varB.txt

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


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Build a report (pdf)

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References

1. Jager T, Albert C, Preuss T, Ashauer R. 2011. General Unified Threshold Model of Survival-a Toxicokinetic-Toxicodynamic Framework for Ecotoxicology. Environ. Sci. Technol. 45:2529–2540.
2. Ashauer R, Albert C, Augustine S, Cedergreen N, Charles S, Ducrot V, Focks A, Gabsi F, Gergs A, Goussen B, Jager T, Kramer NI, Nyman A-M, Poulsen V, Reichenberger S, Schäfer RB, Van den Brink PJ, Veltman K, Vogel S, Zimmer EI, Preuss TG. 2016. Modelling survival: exposure pattern, species sensitivity and uncertainty. Nat. Sci. Rep. 6:29178.
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. 16: 5377. Available at 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. 21:1828–1840.
5. Baudrot V, Veber P, Gence G, Charles S. 2018. Fit GUTS reduced models online: from theory to practice. Integrated Environmental Assessment and Management. 14:625–630.

Staff and contributors

Sandrine CHARLES , professor at University Lyon 1
Virgile BAUDROT , post-doc at INRA
Aurélie SIBERCHICOT , engineer at University Lyon 1
Maud REPELLIN, bachelor student at University Lyon 1