Research projects

Classic and temporal mixture synergism in terrestrial ecosystems: prevalence, mechanisms and impacts

Our team, led by Dr David Spurgeon (CEH, UK), has been awarded £1m for a four-year project to investigate the detailed mechanisms through which mixtures of pesticides and other chemicals affect terrestrial invertebrates. Comprising researchers from CEH, University of Cardiff, University of York and Imperial College, this project will look at synergism – where the interaction between various chemicals has a greater impact than the individual effects added together. We will use a range of ecological, analytical, genetic and modelling methods to identify cases where a mixture of exposures results in greater effects than can be predicted by current widely used models, the biological causes of such effects and their impact on invertebrate populations and communities.

 

Funded by: NERC

Period: 2019 - 2022

Co-I responsible for modelling WP: Roman Ashauer

 

Modelling chronic toxicity in terrestrial mammals

Small mammals (e.g. field voles, wood mice) contribute to ecosystem services both in their own right and as prey for iconic predators such as birds of prey. In order to maintain food security while preserving ecosystem services it is important to understand the mechanisms of how different pesticide exposure patterns lead to ecotoxicological effects under field conditions. We will develop a toxicokinetic-toxicodynamic (TKTD) model to better understand, simulate and predict toxic effects of pesticides on wildlife, in particular effects on growth of small mammals. Existing laboratory toxicity studies with rats and mice will be used to develop and calibrate the model and to develop a better in vitro to in vivo toxicity extrapolation method.

 

Funded by: BBSRC and Syngenta (CASE studentship)

Period: 2016 - 2020

PI: Roman Ashauer, Co-I: Pernille Thorbek

 

CEFIC-LRI ECO 39 & 39.2: Review, ring-test and guidance for TKTD modelling

In this project we will review the state of the science of TKTD modelling in general and develop a roadmap towards broader applicability in chemical risk assessment. We will also write guidance on how to use GUTS for environmental risk assessment of chemicals. Underpinning our recommendations and guidance will be a ring-test of different software implementations of the General Unified Threshold model of Survival (GUTS). The results from CEFIC-LRI ECO39 suggested that we needed a user-friendly, robust, freely-available and open-source software for standard GUTS applications. The ECO39.2 extension will produce such a tool.

 

Funded by: CEFIC-LRI

Period: Jan - Dec 2017, Aug 2018 - Dec 2019

PI: Roman Ashauer, Co-I: Tjalling Jager

 

Microplate system for respiration measurement

A pump priming project to purchase and test a new piece of equipment.

 

Funded by: University of York

Period: 2016

PI: Roman Ashauer (several Co-Is at UoY)

 

Intelligence led assessment of pharmaceuticals in the environment (iPiE)

Minute amounts of the active ingredients in medicines get into the environment in a variety of ways. However, we still know little about what happens to medicines after release into the environment and what effect they have on wildlife. The iPiE project’s goal is to develop a framework that will provide methodologies to prioritise new and existing medicinal compounds for a comprehensive environmental risk assessment.

 

Funded by: EU-IMI

Period: 2015 - 2018

PI: Alistair Boxall, Co-I: Roman Ashauer

 

Ecotoxicological Effect Modelling

We are working with Unilever’s Safety & Environmental Assurance Centre (SEAC) in Colworth to develop capability in the development and application of ecological models to support risk-based decision making. The specific aim is to develop a modelling framework for environmental risk assessment of down-the-drain chemicals that integrates toxicokinetics, toxicodynamics and population dynamics with environmental stress.


Funded by: Unilever

Period: 2015 - 2018

PI: Roman Ashauer


Resilience & ecology of aquatic nanocosms under chemical stress

The project aim is to develop a rapid, small-scale, aquatic multi-species test system (nanocosm) and investigate its resilience under chemical stress. We will study the response of the system to multiple stressors (e.g. synthetic chemicals, nutrients) looking for hysteresis effects and critical transitions. These experiments will then be used for testing and improving ecological effect models.


Funded by: FERA & Environment Department, UoY

Period: 2014 - 2017

PI: Roman Ashauer, Co-I: Rachel Benstead


As simple as possible: a modelling approach to upscale the relevance of ecotoxicological studies (ASAP)

A big discrepancy exists between the increasing demand for ecological realism in regulatory risk assessment and the effective implementation of ecotoxicological studies aimed at assessing the adverse effect of stressors at the population or higher level. The effect of toxicants is commonly measured on individuals as a proxy for the effect on populations but the actual population level impacts are very hard to determine. Ecological modelling can overcome this challenge. However,
until now the complexity in the application of these models has presented a serious hurdle for their use in ecotoxicology. In this study we propose the application of a simple generic toxicokinetic-toxicodynamic model that integrates life-history traits such as growth, reproduction, maintenance and survival in one model organism to assess adverse effects of three different metals over time. We will carry out experiments to calibrate and test the model. The calibration of the model will allow the identification of the physiological modes of action of each metal, unraveling the different ways the chemicals can affect the life-cycle of the organism.


Funded by: Marie-Curie IEF for Olivia Campana

Period: 2014 - 2016

PI: Roman Ashauer, Co-I: Olivia Campana


Toxicokinetics and biotransformation in aquatic invertebrates (TOXKINBIO)

Pesticides, pharmaceuticals and other chemicals support our modern standard of life, but their use can have detrimental impacts on our environment. We want to study the uptake, biotransformation and elimination (toxicokinetics) of pharmaceuticals in aquatic invertebrates. We aim to identify and model biotransformation pathways in four different species. Studying the comparative toxicokinetics of small, aquatic invertebrates is of great interest because it contributes to understanding evolutionary and environmental mechanisms and causes of differences in species sensitivity to chemicals.


Funded by: EU Marie-Curie Career Integration Grant

Period: 2014 - 2018

PI: Roman Ashauer


Pesticide avoidance behaviour of non-target arthropods and its population level consequences in spatially heterogeneous exposure landscapes (PANTA)

Insecticides are used to control target pest arthropods (insects and other bugs) which attack crops. However, non-target arthropods, for example butterflies and lacewings, can also be affected. Some of these non-target arthropods are predators that can help to control pests naturally, and all are part of the farmland biodiversity. It is therefore very important to assess the potential effects of pesticides on these non-target arthropods. When farmers apply pesticides there will always be patches where concentrations are high and patches where concentrations are low. This applies both to the crops and the land surrounding the crops onto which some pesticide may drift, e.g. field margins and hedges. A key question is therefore whether the non-target arthropods can avoid the high concentration patches of pesticides to avoid exposure and toxicity, and what impact this has on their populations. Thus we ask:

  • How patchy are pesticide concentrations in and near fields?
  • Can mobile arthropods avoid pesticides?
  • How are populations of non-target arthropods affected by different levels of patchiness of pesticide exposure?

Funded by: BBSRC & ADAMA

Period: 2014 - 2018

PI: Roman Ashauer, Co-I: Mark Hodson


Modelling Toxicity Behaviour of Engineered Nanoparticles (ModNanoTox)

ModNanoTox will develop models describing the behaviour of engineered nanoparticles in the environment and organisms. The objective of our workpackage  is to model toxicity at the organism level using bioaccumulation based toxicokinetic-toxicodynamics models, which integrate experimental data on nanoparticle bioaccumulation kinetics and toxicity. Using a toxicokinetic-toxicodynamic framework we aim to identify mechanisms of toxic action and deduce general principles of nanoparticle toxicity.

 

Funded by: European Union

Period: 2011 - 2013

PI: Kristin Schirmer, co-applicant: Roman Ashauer

 

Mechanistic Effect Models for Ecological Risk Assessment of Chemicals (CREAM)

CREAM is a Marie Curie Initial Training Network with 13 partner institutions and 10 associated partners. Research within CREAM consists of 20 PhD and three postdoc projects developing ecological or ecotoxicological models for the risk assessment of chemicals, including empirical work.

  • Determination of toxicity by compound and species characteristics at different scales (individual and population) - SCALES 1. This project is carried out by Anna-Maija Nyman at Eawag.
  • Predicting toxicity to fish based on in vitro data via a two step model - FISH 1. This project is carried out by Julita Stadnicka at Eawag.
  • Influence of time-varying patterns of exposure on chronic and sub-lethal effects- SCALES 2. This project is carried out by Annika Agatz at the University of York in the UK.

Funded by: European Union

Period: 2009 - 2013

PI: Roman Ashauer, co-applicant: Kristin Schirmer

 

Improving the Definition of Water Quality Criteria: linking organism recovery times to mechanism of action and acute-to-chronic ratios

The project systematically investigates a novel approach to aquatic ecotoxicology which is based on measuring and simulating toxic processes in time. It applies the mechanistic understanding of toxic effects on aquatic organisms to develop a process-based interpretation of acute-to-chronic (ACR) datasets. Furthermore this research will establish a better understanding of how organisms recover from exposure to different chemicals and how that recovery is related to mechanisms of action (MEoA) as well as how acute toxicity is related to chronic effects. Ultimately, this study will inform risk assessment and facilitate the definition of water quality criteria based on evidence about the time-course of toxic effects (ACR) and mechanistic information (MEoA).

 

Funded by: CEFIC-SETAC Innovative Science Award

Period: Since 2007

PI: Roman Ashauer

 

Dynamische Effektmodellierung für Gewässerbewertung und Risikoabschätzung (DynaRisk)

Dynamic risk assessment of fluctuating or pulsed exposures to chemicals is a project funded by the Swiss Federal Office for the Environment. The objective is to develop a method to assess the risk to aquatic systems posed by fluctuating concentrations of pesticides, biocides, pharmaceuticals or veterinary medicines.

 

Funded by: BAFU (Swiss EPA)

Period: 2009 - 2012

PI: Roman Ashauer

 

Toxicokinetic and Toxicodynamic Models in Aquatic Ecotoxicology for a Mechanistic Link between Bioconcentration and Effects

This study aims at a better understanding of toxic effects from anthropogenic pollutants on aquatic organisms and better tools for aquatic risk assessment. Toxicokinetic-toxicodynamic models (TK-TD models) serve both purposes. They can simulate and predict the time-course of toxic effects on aquatic organisms after exposure to xenobiotics. Hence the project consists of mathematical modelling and ecotoxicological experiments with organic xenobiotic compounds.

 

We investigate the relationships between the toxicokinetic and toxicodynamic parameters on the one hand and compound- and species-specific properties on the other hand. Systematically studying the role of the mechanism of toxic action, the reversibility of effect and the threshold of toxicity will establish a process-based understanding of the toxicodynamics. We chose 15 chemicals of four different mode-of-action classes to cover a range of TD variability. A gradient of TK related properties within these compounds allows one to separate influences of TK and TD on overall toxic effects.

 

Funded by: SNF (Swiss National Science Foundation)

Period: 2008 - 2011

PI: Beate Escher