Mechanistic modelling of toxicokinetic processes within Myriophyllum spicatum

Heine, Simon; Schmitt, Walter; Schäffer, Andreas; Görlitz, Gerhard; Buresova, H.; Arts, G.H.P.; Preuß, Thomas G.

doi:10.1016/j.chemosphere.2014.07.065

Cited by 11 publications

(19 citation statements)

References 27 publications

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“…(); Heine et al. (, , ). External factors affecting chemical uptake or growth are given in blue, internal chemical concentrations in orange and the different rate constants affecting biomass growth of the plants or algae in the respective models are given in green.…”

Section: Concepts and Examples For Tktd Modelling Approachesmentioning

confidence: 99%

“…Myriophyllum is rooted, hence, the growth model needs at least root, stem and shoot compartments, which are explicitly introduced (Heine et al., ) and modelled in Heine et al. (, ). In an extended Myriophyllum model (Hommen et al., ), rhizomes – which are energy storage organs – are also included to be able to model growth and allocation patterns over longer timescales, e.g.…”

Section: Concepts and Examples For Tktd Modelling Approachesmentioning

confidence: 99%

“…The second paper focusses on describing and parameterising the TK‐processes for several herbicides, including both sulfonylurea and photo‐system II inhibitors. Also, they determine cuticular permeability for chemicals based on their log K ow (Heine et al., ). The final paper describes and parameterises the toxicodynamic model using the sulfonylurea iofensulfuron (Heine et al., ).…”

Section: Models For Primary Producersmentioning

confidence: 99%

See 2 more Smart Citations

Scientific Opinion on the state of the art of Toxicokinetic/Toxicodynamic (TKTD) effect models for regulatory risk assessment of pesticides for aquatic organisms

Ockleford¹,

Adriaanse²,

Berny³

et al. 2018

EFS2

157

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Following a request from EFSA, the Panel on Plant Protection Products and their Residues (PPR) developed an opinion on the state of the art of Toxicokinetic/Toxicodynamic (TKTD) models and their use in prospective environmental risk assessment (ERA) for pesticides and aquatic organisms. TKTD models are species-and compound-specific and can be used to predict (sub)lethal effects of pesticides under untested (time-variable) exposure conditions. Three different types of TKTD models are described, viz., (i) the 'General Unified Threshold models of Survival' (GUTS), (ii) those based on the Dynamic Energy Budget theory (DEBtox models), and (iii) models for primary producers. All these TKTD models follow the principle that the processes influencing internal exposure of an organism, (TK), are separated from the processes that lead to damage and effects/mortality (TD). GUTS models can be used to predict survival rate under untested exposure conditions. DEBtox models explore the effects on growth and reproduction of toxicants over time, even over the entire life cycle. TKTD model for primary producers and pesticides have been developed for algae, Lemna and Myriophyllum. For all TKTD model calibration, both toxicity data on standard test species and/or additional species can be used. For validation, substance and species-specific data sets from independent refined-exposure experiments are required. Based on the current state of the art (e.g. lack of documented and evaluated examples), the DEBtox modelling approach is currently limited to research applications. However, its great potential for future use in prospective ERA for pesticides is recognised. The GUTS model and the Lemna model are considered ready to be used in risk assessment. This is an open access article under the terms of the Creative Commons Attribution-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited and no modifications or adaptations are made.The EFSA Journal is a publication of the European Food Safety Authority, an agency of the European Union. As a third deliverable of this mandate, the PPR Panel is asked to develop a Scientific Opinion describing the state of the art of Toxicokinetic/Toxicodynamic (TKTD) models for aquatic organisms and prospective environmental risk assessment (ERA) for pesticides with the main focus on: (i) regulatory questions that can be addressed by TKTD modelling, (ii) available TKTD models for aquatic organisms, (iii) model parameters that need to be included and checked in evaluating the acceptability of regulatory relevant TKTD models, and (iv) selection of the species to be modelled.Chapter 2 presents the underlying concepts, terminology, application domains and complexity levels of three different classes of TKTD models intended to be used in risk assessment, viz., (i) the 'General Unified Threshold models of Survival' (GUTS), (ii) toxicity models derived from the Dynamic Energy Budget theory (DEBtox models), and (iii) models for primary producers. All ...

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Section: Concepts and Examples For Tktd Modelling Approachesmentioning

confidence: 99%

Section: Concepts and Examples For Tktd Modelling Approachesmentioning

confidence: 99%

Section: Models For Primary Producersmentioning

confidence: 99%

See 1 more Smart Citation

Scientific Opinion on the state of the art of Toxicokinetic/Toxicodynamic (TKTD) effect models for regulatory risk assessment of pesticides for aquatic organisms

Ockleford¹,

Adriaanse²,

Berny³

et al. 2018

EFS2

157

View full text Add to dashboard Cite

show abstract

“…To predict the impact of short‐term iofensulfuron exposures on M. spicatum , a toxicokinetic and toxicodynamic growth model was used. A detailed description of the growth and of the toxicokinetic model can be found in Heine et al . These publications contain all equations considered and a complete parameterization of the model.…”

Section: Methodsmentioning

confidence: 99%

“…The aim of the present study was to integrate toxicodynamics in an already published toxicokinetic growth model of Myriophyllum spicatum , to develop a model that is able to predict the effects of time‐variable chemical exposure. To show the applicability of the model, the effects of 2 short‐term exposure scenarios of a sulfonylurea compound that causes adverse effects on the growth of aquatic plants were predicted.…”

Section: Introductionmentioning

confidence: 99%

A toxicokinetic and toxicodynamic modeling approach using Myriophyllum spicatum to predict effects caused by short‐term exposure to a sulfonylurea

Heine

Schild

Schmitt

et al. 2015

Enviro Toxic and Chemistry

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Toxicokinetic and toxicodynamic models are a promising tool to address the effects of time-variable chemical exposure. Standard toxicity tests usually rely on static concentrations, but these chemical exposure patterns are unlikely to appear in the field, where time-variable exposure of chemicals is typical. In the present study, toxicodynamic processes were integrated into an existing model that includes the toxicokinetics and growth of the aquatic plant Myriophyllum spicatum, to predict the impact on plant growth of 2 iofensulfuron short-term exposure patterns. To establish a method that can be used with standard data from risk assessments, the toxicodynamics of iofensulfuron were based on effect data from a 14-d standard toxicity test using static concentrations. Modeling showed that the toxicokinetic and toxicodynamic growth model of M. spicatum can be successfully used to predict effects of short-term iofensulfuron exposure by using effect data from a standard toxicity test. A general approach is presented, in which time-variable chemical exposures can be evaluated more realistically without conducting additional toxicity studies.

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How TK‐TD and population models for aquatic macrophytes could support the risk assessment for plant protection products

Hommen

Schmitt

Heine

et al. 2015

Integr Envir Assess & Manag

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This case study of the Society of Environmental Toxicology and Chemistry (SETAC) workshop MODELINK demonstrates the potential use of mechanistic effects models for macrophytes to extrapolate from effects of a plant protection product observed in laboratory tests to effects resulting from dynamic exposure on macrophyte populations in edge-of-field water bodies. A standard European Union (EU) risk assessment for an example herbicide based on macrophyte laboratory tests indicated risks for several exposure scenarios. Three of these scenarios are further analyzed using effect models for 2 aquatic macrophytes, the free-floating standard test species Lemna sp., and the sediment-rooted submerged additional standard test species Myriophyllum spicatum. Both models include a toxicokinetic (TK) part, describing uptake and elimination of the toxicant, a toxicodynamic (TD) part, describing the internal concentration-response function for growth inhibition, and a description of biomass growth as a function of environmental factors to allow simulating seasonal dynamics. The TK-TD models are calibrated and tested using laboratory tests, whereas the growth models were assumed to be fit for purpose based on comparisons of predictions with typical growth patterns observed in the field. For the risk assessment, biomass dynamics are predicted for the control situation and for several exposure levels. Based on specific protection goals for macrophytes, preliminary example decision criteria are suggested for evaluating the model outputs. The models refined the risk indicated by lower tier testing for 2 exposure scenarios, while confirming the risk associated for the third. Uncertainties related to the experimental and the modeling approaches and their application in the risk assessment are discussed. Based on this case study and the assumption that the models prove suitable for risk assessment once fully evaluated, we recommend that 1) ecological scenarios be developed that are also linked to the exposure scenarios, and 2) quantitative protection goals be set to facilitate the interpretation of model results for risk assessment.

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Mechanistic modelling of toxicokinetic processes within Myriophyllum spicatum

Cited by 11 publications

References 27 publications

Scientific Opinion on the state of the art of Toxicokinetic/Toxicodynamic (TKTD) effect models for regulatory risk assessment of pesticides for aquatic organisms

Scientific Opinion on the state of the art of Toxicokinetic/Toxicodynamic (TKTD) effect models for regulatory risk assessment of pesticides for aquatic organisms

A toxicokinetic and toxicodynamic modeling approach using Myriophyllum spicatum to predict effects caused by short‐term exposure to a sulfonylurea

How TK‐TD and population models for aquatic macrophytes could support the risk assessment for plant protection products

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