Population-level impacts of pesticide-induced chronic effects on individuals depend more on ecology than toxicology.

The current method for assessing long-term risk of pesticides to mammals in the EU is based on the individual rather than the population-level and lacks ecological realism. Hence there is little possibility for regulatory authorities to increase ecological realism and understanding of risks at the population-level. Here we demonstrate how, using ABM modelling, assessments at the population-level can be obtained even for a pesticide with complex long-term effects such as epigenetic transmission of reproductive depression. By objectively fitting nonlinear models to the simulation outputs it was possible to compare population depression and recovery rates for a range of scenarios in which toxicity and exposure factors were varied. The system was differentially sensitive to the various factors, but vole ecology and behaviour were at least as important predictors of population-level effects as toxicology. This emphasises the need for greater focus on animal ecology in risk assessments.

[1]  D. Veeramachaneni,et al.  Disruption of sexual function, FSH secretion, and spermiogenesis in rabbits following developmental exposure to vinclozolin, a fungicide. , 2006, Reproduction.

[2]  D. Elston,et al.  To graze or not to graze? Sheep, voles, forestry and nature conservation in the British uplands , 2006 .

[3]  D R Crocker,et al.  Estimating the Exposure of Birds and Mammals to Pesticides in Long-term Risk Assessments , 2005, Ecotoxicology.

[4]  Peter Odderskær,et al.  ALMaSS, an agent-based model for animals in temperate European landscapes , 2003 .

[5]  Scott Ferson,et al.  Role of Ecological Modeling in Risk Assessment , 2003 .

[6]  P. Calow,et al.  Is the per capita rate of increase a good measure of population‐level effects in ecotoxicology? , 1999 .

[7]  Trevor Hastie,et al.  Statistical Models in S , 1991 .

[8]  Douglas M. Bates,et al.  Nonlinear Regression Analysis and Its Applications , 1988 .

[9]  P. Mineau.  A Review and Analysis of Study Endpoints Relevant to the Assessment of “Long Term” Pesticide Toxicity in Avian and Mammalian Wildlife , 2005, Ecotoxicology.

[10]  C. Walker,et al.  Organochlorine insecticide residues in wild birds in Britain. , 1967, Journal of the science of food and agriculture.

[11]  R. Sibly,et al.  Population-level Assessment of Risks of Pesticides to Birds and Mammals in the UK , 2005, Ecotoxicology.

[12]  R M Sibly,et al.  Risk Assessment of UK Skylark Populations Using Life-History and Individual-Based Landscape Models , 2005, Ecotoxicology.

[13]  S. Ferson,et al.  Realism and Relevance of Ecological Models Used in Chemical Risk Assessment , 2003 .

[14]  J. Cairns.  Will there ever be a field of landscape toxicology , 1993 .

[15]  C. Walker.  Ecotoxicity testing of chemicals with particular reference to pesticides. , 2006, Pest management science.

[16]  H. Leirs,et al.  Effects of grazing intensity on small mammal population ecology in wet meadows , 2005 .

[17]  David R. Anderson,et al.  Model selection and multimodel inference : a practical information-theoretic approach , 2003 .

[18]  Michael K. Skinner,et al.  Epigenetic Transgenerational Actions of Endocrine Disruptors and Male Fertility , 2005, Science.

[19]  Alan R. Johnson.  Landscape Ecotoxicology and Assessment of Risk at Multiple Scales , 2002 .

[20]  C. D. S. Tomlin,et al.  The Pesticide Manual , 2003 .

[21]  Peter Odderskær,et al.  Ukrudtsstriglingens effekter på dyr, planter og ressourceforbrug , 2006 .

[22]  M. Skinner,et al.  Transgenerational epigenetic imprinting of the male germline by endocrine disruptor exposure during gonadal sex determination. , 2006, Endocrinology.

[23]  Richard S Bennett,et al.  A New Interpretation of Avian and Mammalian Reproduction Toxicity Test Data in Ecological Risk Assessment , 2005, Ecotoxicology.

[24]  M. Etterson,et al.  On the Use of Published Demographic Data for Population-Level Risk Assessment in Birds , 2006 .

[25]  M. Skinner,et al.  Endocrine disruptor vinclozolin induced epigenetic transgenerational adult-onset disease. , 2006, Endocrinology.

[26]  Richard S. Bennett,et al.  Estimating Pesticide Effects on Fecundity Rates of Wild Birds Using Current Laboratory Reproduction Tests , 2006 .

[27]  L. Gray,et al.  Environmental antiandrogens: low doses of the fungicide vinclozolin alter sexual differentiation of the male rat , 1999, Toxicology and industrial health.

[28]  P. E. Gibbs,et al.  Tributyltin-induced imposex in stenoglossan gastropods: Pathological effects on the female reproductive system , 1991 .

[29]  L. Hansson.  Spatial Dynamics of Field Voles Microtus agrestis in Heterogeneous Landscapes , 1977 .

[30]  R. Whitehead,et al.  The UK Pesticide Guide 2006 , 2008 .

[31]  Cino Pertoldi,et al.  Impact Assessment Predicted by Means of Genetic Agent-Based Modeling , 2004, Critical reviews in toxicology.

[32]  A. Myllymaki.  Demographic mechanisms in the fluctuating populations of the field vole Microtus agrestis , 1977 .