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PresentationsCrop Protection2019

Topeka shiner populations in the context of multiple stressors: a hybrid modeling approach

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SETAC 2019, Platform 687
Toronto, Ontario, Canada
Session Title: Integrating Pest Management, Risk Assessment and Environmental Sustainability
Thursday, November 7, 2019
10:00 am, Room 718B

Abstract:
Threatened or endangered species face challenges to their continued existence from multiple stressors. For example, habitat loss and modification were indicated as substantial threats to the Topeka shiner (Notropis topeka), a small cyprinid fish endemic to the US Midwest, when it was listed under the Endangered Species Act. Topeka shiner habitats are associated with intensive row crop agriculture, overgrazing, urbanization, road construction, and hydrologic alteration. However, assessments of risks to the species are usually limited to individual factors, such as direct effects from potential exposures to pesticides. We developed a hybrid modelling approach to assess Topeka shiner population dynamics and viability within the context of multiple factors including physical habitat characteristics, water quality, and land management practices. Topeka shiner habitat restoration efforts in Iowa are focused on restoring oxbows. Therefore, we simulated physical and chemical characteristics of these oxbow habitats, including their food web structure, as well as aspects of Topeka shiner biology and ecology. Land management was modeled indirectly by characterizing associated alterations of environmental inputs to the modeled oxbow. Land management influences included alterations to oxbow hydrology, temperature, light exposure, and influxes of nutrients, sediments, and pesticides. We analyzed scenarios of realistic ranges of these conditions in Iowa oxbows to assess their implications for long-term population dynamics of the Topeka shiner. With this hybrid modeling approach, we present a methodology for integrated assessments of ecological risks posed by land management and benefits of conservation measures designed to recover listed species. This modelling approach is intended to complement endangered species assessment by informing conservation/stewardship activities in an effort to enhance species viability.

A. Schmolke (Waterborne), S. Bartell (Cardno), C. Roy (Waterborne), N. Green (Waterborne), D. Perkins (Waterborne), N. Galic (Syngenta), R. Brain (Syngenta). Topeka shiner populations in the context of multiple stressors: a hybrid modeling approach. Platform 687, SETAC 2019. Toronto, Ontario, Canada.

PostersCrop Protection2019

Sources, characteristics and opportunities for pesticide use and usage information applied to listed species risk assessment

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SETAC 2019, RP225
Toronto, Ontario, Canada
Session Title: Integrating Pest Management, Risk Assessment and Environmental Sustainability
Thursday, November 7, 2019
8:00 am, Exhibit Hall

Abstract:
The challenges inherent in national-level pesticide endangered species risk assessments are many, varied and have been the topic of meetings, workshops, presentations and publications for many years. One challenge is the identification and incorporation of pesticide usage information in the risk assessment process. Pesticide “usage” differs from pesticide “use”, where “use” is defined by registered labels and describes limits on how the pesticide may be applied (i.e., maximum rates and number of applications), while “usage” describes documented applications with specific information on each individual event. Incorporating usage information into the risk characterization during the Biological Evaluation and Biological Opinion development process is an area of renewed interest. This poster will describe several sources of pesticide usage information (e.g., USDA Agricultural Chemical Use Program, CA DPR Pesticide Use Reporting), and how relevant field-level pesticide application information can be extracted. Examples will be given showing how these data can be utilized to refine our understanding of specific active ingredients and their associated spatial and temporal variation across use areas, and how this can inform the exposure analysis within each Step of the ESA consultation process.

C. Holmes (Applied Analysis Solutions), J. Amos (Waterborne), M. Kern (Waterborne), N. Snyder (Waterborne), J. Cowles (TKI), K. Henry (TKI).  Sources, characteristics and opportunities for pesticide use and usage information applied to listed species risk assessment. Poster, SETAC 2019. RP225. Toronto, Ontario, Canada.

PresentationsCrop Protection2019

Pop-GUIDE: Population modeling Guidance, Use, Interpretation, and Development for Ecological Risk Assessment

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SETAC 2019, Platform 475
Toronto, Ontario, Canada
Session Title: Incorporating New Approach Methodologies to Improve Ecological Risk Assessment – Part 1
Wednesday, November 6, 2019
11:00 am, Room 718B

Abstract:
The assimilation of population models into the Ecological Risk Assessment (ERA) process has been hindered by their range of complexity, uncertainty, resource investment, and data availability. Likewise, translating model outputs into endpoints that can be used by risk assessors has been challenging. Recent research efforts have begun to tackle these challenges by creating an integrated Modeling Framework and Decision Guide to aid the development of population models with respect to ERA objectives and data availability. In the Framework, the trade-offs associated with the generality, realism, and precision of an assessment are used to guide the development of a population model commensurate with the protection goal. The Decision Guide provides risk assessors with a stepwise process to assist them in developing a conceptual model that is appropriate for the assessment objective and available data. We have merged the Decision Guide and Modeling Framework into a comprehensive approach for the development of population models for ERA that is applicable across regulatory statutes and assessment objectives. In Phase 1 of Pop-GUIDE (Population modeling Guidance, Use, Interpretation, and Development for Ecological Risk Assessment), an approach is presented to guide assessors through the trade-offs of ERA generality, realism, and precision and translate these trade-offs into model objectives. In Phase 2, available data are assimilated and characterized as general, realistic, and/or precise. Phase 3 provides a series of dichotomous questions to develop a conceptual model that matches the complexity and uncertainty appropriate for the assessment that is in concordance with the available data. This phase guides model developers and users to ensure comprehension and transparency of the modeling process. We introduce Pop-GUIDE using fish as an example taxon and the Federal Insecticide Fungicide and Rodenticide Act (FIFRA) as a regulatory statute example.

S. Raimondo (USEPA), A. Schmolke (Waterborne), C. Accolla (University of Minnesota), J. Awkerman (USEPA), M. Etterson (USEPA), N. Galic (Syngenta), A. Moore (University of Minnesota), M. Vaugeois (University of Minnesota), P. Rueda-Cediel (University of Minnesota), N. Pollesch (USEPA), V. Forbes (University of Minnesota). Pop-GUIDE: Population modeling Guidance, Use, Interpretation, and Development for Ecological Risk Assessment. Platform 475, SETAC 2019. Toronto, Ontario, Canada.

PresentationsCrop Protection2019

Applying the Mechanistic Honey Bee Colony Model BEEHAVE to Inform Large Colony Feeding Study Design

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SETAC 2019, Platform 281
Toronto, Ontario, Canada
Session Title: Pesticides and Pollinators: Assessing Potential Risks at Colony and Population Level
Tuesday, November 5, 2019
8:40 am, Room 716B

Abstract:
In higher-tier studies aiming to assess pesticide exposure and effects to honey bees at the colony level, other factors can impact colonies and confound the analysis of potential pesticide impacts. Large colony feeding studies (LCFS) are sometimes affected by high losses of control colonies, indicating that stressors such as limited resource availability, weather, diseases and beekeeping activities may be influential. In the current project commissioned by the Pollinator Research Task Force, we assessed the study design and environmental conditions experienced by the untreated control colonies across seven LCFSs. Overwintering success in these control colonies differed considerably among the studies. In addition, the studies differed with respect to initial colony conditions, amount and timing of sugar feeding, landscape composition around study apiaries and weather. We applied the mechanistic colony model BEEHAVE to systematically assess the impact of study design and environmental conditions on control colonies. We first calibrated BEEHAVE to a subset of the studies, validated it with the remaining studies, and then used it to run simulations that changed only one variable at a time. The goal of the project was to inform study design that leads to increased likelihood of control colony overwintering success. From the simulations, the initial status of the colonies as well as the sugar feeding pattern were more important for fall colony condition than resource availability in the landscape and weather. Larger honey stores present in the colonies at study initiation, greater feeding amounts and earlier supplemental feedings (beginning in late summer to early fall) were the main factors that led to larger colony sizes and honey stores in the fall. This information can be used to inform the standardization of a study design, which in turn can increase the likelihood of overwintering survival in untreated controls and help ensure that studies are comparable. This project demonstrates how a mechanistic model can be used to inform study designs for higher-tier effects studies. Mechanistic models like BEEHAVE could further be applied to supplement higher-tier risk assessments, for instance, by extrapolating to non-tested exposure scenarios and environmental conditions and therefore potentially reducing the number of higher-tier studies.

F. Abi-Akar (Waterborne), A. Schmolke (Waterborne), C. Roy (Waterborne), N. Galic (Syngenta), S. Hinarejos (Valent).  Applying the Mechanistic Honey Bee Colony Model BEEHAVE to Inform Large Colony Feeding Study Design. Platform 281, SETAC 2019. Toronto, Ontario, Canada.

PostersCrop Protection2019

The utility of a weight-at-emergence endpoint in the 22-day larval assay for a pollinator risk assessment

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SETAC 2019, TP274
Toronto, Ontario, Canada
Session Title: Pesticides and Pollinators: Assessing Potential Risks at Colony and Population Level
Tuesday, November 5, 2019
8:00 am, Exhibit Hall

Abstract:
USEPA has identified the 22-day honey bee larval assay as a Tier 1, screening-level toxicity study for assessing pesticide risk to bees. This repeat-dose larval study is based on the Organization for Economic Co-operation and Development Guidance Document 239, and methodology provided by Schmehl et al.(2016). During this study, first instar larvae are transferred from healthy colonies to grafting cells (day 1) and treated diet is administered between days 3 and 6. Survival is assessed at multiple stages of the test: daily between days 4 and 8 for larvae; day 15 for pupae; and day 22 (emergence time) for adults. However, at the request of the USEPA, adult weight at emergence has also been included as a study endpoint. The Pollinator Research Task Force (PRTF) is conducting an endpoint evaluation to compare the sensitivity of adult weight at emergence to that of the survival endpoint in this study design. A database was developed based on anonymized study data from PRTF member companies, as well as applicable studies from the open literature. The compiled data were evaluated both empirically and statistically with regard to endpoint sensitivity. Statistically significant effects based on survival and adult weight at emergence were compared. No- and Lowest-Observed-Effect Dose (NOED and LOED) values, as well as 50% lethal and effect dose (LD50 and ED50) values were also compared between the endpoints. Coefficients of variation (CVs) were compared graphically and statistically to quantify the variability in each metric and determine significant differences. A pairing structure was also used to assess correlation, which could be graphed and statistically analyzed. This presentation outlines the methods used during this project, the results of the endpoint analyses, and concluding findings on the endpoint sensitivity comparison between survival and adult weight at emergence.

B. Sharma (FMC), D. Schmehl (Bayer), J. Collins (Waterborne), F. Abi-Akar (Waterborne), J. Jackson (Waterborne).  The utility of a weight-at-emergence endpoint in the 22-day larval assay for a pollinator risk assessment. Poster, SETAC 2019. TP274. Toronto, Ontario, Canada.

PostersCrop Protection2019

Practical Advancements in Endangered Species Risk Assessment Efficiency

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SETAC 2019, TP253
Toronto, Ontario, Canada
Session Title: Ecological Risk Assessment: What Matters and Prioritization of Resources
Tuesday, November 5, 2019
8:00 am, Exhibit Hall

Abstract:
With the release of the Environmental Protection Agency (EPA) and National Marine Fisheries Service (NMFS) organophosphate case studies for endangered species risk assessment, it became clear that the methods used in the biological evaluations and biological opinion need refinement for identifying risk to listed species and the critical habitat on which they may depend. With hundreds of pesticide registration actions annually, and more than 1,660 species listed under the Endangered Species Act, it is critical to be able to conduct a scientifically defensible risk assessment efficiently with limited time and resources. However, confidence must be high that the listed species or the critical habitat on which they depend can readily be identified as being not at risk, or at potential risk. The recently released EPA revised method for developing biological evaluations addresses some aspects of these short comings, by recognizing early in the problem formulation process that some listed species will not be exposed to a pesticide for a variety of reasons (e.g., they are extinct or extirpated; only found on federal lands). However, there are many possible additional considerations that matter, can be accounted for, and may vary on a pesticide by pesticide basis. These include label restrictions, simple spatial refinement, specific fate/behavior characteristics, listed species life history information, known and previously evaluated pesticide tolerances, and other factors. In a CropLife America funded project, these practical advancements are being identified and evaluated for use in the problem formulation process. In this presentation, the carbamate pesticide carbaryl is used to evaluate the impact of these factors on the endangered species risk assessment process, along with examples from other chemistries to more clearly show their utility.

S. Teed (Intrinsik), M. Kern (Waterborne), J. Cowles (TKI).  Practical Advancements in Endangered Species Risk Assessment Efficiency. Poster, SETAC 2019. TP253. Toronto, Ontario, Canada.

Crop Protection2019

Landscape-scale field studies to evaluate fate and transport of an agricultural fungicide to farm ponds

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ACS 2019, AGRO 97
San Diego, California
Session Title: Off-Target Transport of Field Applied Agricultural Chemicals: Study Designs, Monitoring, Modelling, & Risk
Monday, August 26, 2019
11:05 am, Ballroom 20B-D, Theater 5

Abstract:
Landscape-scale field studies were conducted to evaluate the fate and transport of benzovindiflupyr, an SDHI fungicide active ingredient, and its major degradation products from cropped areas to receiving farm ponds. Studies were initiated in two locations; one in Georgia with a cotton/peanut/cucurbit crop rotation and another in Missouri with a corn/soybean crop rotation. Applications were made in 2017 and 2018 seasons at maximum labelled rates and typical timing for the respective crops. Depth-integrated pond water samples and sediment core samples were collected on a monthly basis to evaluate residue concentrations over time. Initial residue results in runoff, pond water, and pond sediment will be presented and compared with relevant ecotoxicological endpoints.

A.M. Moore, T. Wiepke, C. Truman (Syngenta Crop Protection), M. Cox (Waterborne), J.P. Hanzas (Stone Environmental).  Landscape-scale field studies to evaluate fate and transport of an agricultural fungicide to farm ponds.  Presentation, ACS 2019.  AGRO 97. San Diego, California.

PresentationsCrop Protection2019

Leveraging national compensatory mitigation conservation offset strategies to proactively address endangered species section 7 authorized take of residual, unavoidable impacts permitted within national scale pesticide biological options

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ACS 2019, AGRO 371
San Diego, California
Session Title: Interpreting, Communicating & Managing Risk in the FIFRA/ESA Regulatory Setting
Thursday, August 29, 2019
11:10 am, Ballroom 20B-D, Theater 3

Abstract:

The release of the three Organophosphate (and pending Carbamate) national scale endangered species assessments have presented new challenges to the USEPA, NMFS, and USFWS. The Biological Evaluations have identified most species as likely to be adversely affected causing extensive and costly Biological Opinions to be generated. These assessments are designed to determine relative potential risk to each species not of the actual impacts to the species, which is what the USFWS and NMFS must evaluate in Endangered Species Act (ESA) Section 7 consultations. A collaborative process is needed to develop a metric for actual impacts resulting from chemical applications taking place within the “best available information” known habitat ranges of listed species so that the Section 7 consultations can be concluded. When impacts are determined the conservation offsets for those residual, unavoidable impacts, can be included in the authorized permit. Industry and the evaluating agencies can protect species populations and promote species recovery simultaneously, while simultaneously assuring agricultural production and food security needs. In some cases, localized use restrictions, buffers, and reduced rates (minimization and avoidance actions) may offer the needed protections for a specific species population. In other cases, conservation offsets, of a similar spatial and temporal nature to the authorized take may meet both needs of species protection and the agricultural use of crop protection products. This presentation will focus on the transfer of extensive experience in leveraging national compensatory mitigation strategies (Clean Water Act Section 404, Endangered Species Act Sections 7 & 10) to mitigate the effect of a permitted action. Through the offsets incorporated in permit authorization, regulatory requirements are met, crop protection products are available for approved usage, and species protection and recovery are addressed. The national and broad potential product application footprint offers challenges, but solutions may be found if all parties involved use creativity and tested approaches to holistically link the species impacts to recovery plans. The effect is to better leverage both the ESA and EPA authorization processes, resulting in improved endangered species viabilities (less listings, increased recoveries) and national scale pesticide risk assessments that are more practically linked to the landscape.

W. White, J. Bickel, N. Snyder (Waterborne).  Leveraging national compensatory mitigation conservation offset strategies to proactively address endangered species section 7 authorized take of residual, unavoidable impacts permitted within national scale pesticide biological options.  Presentation, ACS 2019.  AGRO 371. San Diego, California.

PostersCrop Protection2019

Addressing multiple factors impacting honey bee colonies in large colony feeding studies with a mechanistic honey bee colony model

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ACS 2019, AGRO 308
San Diego, California
Session Title: Pollinators in Agroecosystems:  Current Science Issues & Risk Assessment Approaches
Wednesday, August 28, 2019
11:30 am, Poster Session

Abstract:

Honey bee Large Colony Feeding Studies (LCFS) are conducted as a novel type of Tier II semi-field study for the determination of potential effects of pesticides on free-foraging whole colonies during and after dietary intake of a known pesticide concentration. This study design represents a progressively more realistic level of refinement compared to individual laboratory-based studies. However, observed winter losses of control colonies indicate that stressors other than pesticides, e.g. resource availability, weather, diseases and beekeeping activities, likely influence colony condition and overwintering survival, confounding the assessment of impacts caused by pesticides. In the current study commissioned by the Pollinator Research Task Force, we apply the mechanistic honey bee colony model BEEHAVE to simulate colony dynamics observed in negative control colonies from multiple colony feeding studies. In the modeling approach, factors impacting colonies can be fully controlled and their impacts on colony condition can be assessed systematically. Study data from control colonies in seven LCFS were available and colony condition data collected in summer and fall were analyzed for predictors of overwintering success of individual colonies. The BEEHAVE simulations were parameterized with apiary-specific data available from the studies, including landscape-level resource availability, weather, initial colony condition and feeding patterns. BEEHAVE was calibrated and validated to simulate reported colony condition across the study period. BEEHAVE simulations with different combinations of external factors were used to assess their importance for colony condition. Colony conditions at study initialization and feeding patterns both influenced the colony condition in the fall, and thus, the probability of overwintering survival. Model simulations with different colony feeding patterns and initial colony conditions were then used to quantitatively estimate colony-level outcomes under conditions deviating from those in the studies. These results provide insight into the importance of factors related to study conditions and can be used to improve and inform LCFS study designs. Pesticide effects can be included in future model analyses, and analyzed in the context of multiple factors that impact colony health and overwintering success.

A. Schmolke, F. Abi-Akar, D. Perkins (Waterborne), N. Galic (Syngenta Crop Protection LLC), S. Hinarejos (Sumitomo Chemical Company Ltd).  Addressing multiple factors imapcting honey bee colonies in large colony feeding studies with a mechanistic honey bee colony model. Poster, ACS 2019.  AGRO 308. San Diego, California.

PostersCrop Protection2019

Common issues in agrochemical risk communication

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ACS 2019, AGRO 290
San Diego, California
Session Title: Environmental Fate, Transport, & DRIFT Modeling of Agrichemicals
Wednesday, August 28, 2019
11:30 am, Poster Session

Abstract:

A great deal of the problems with communicating risk from agrochemical exposure arises from intrinsic uncertainties in exposure and toxicity calculations. The probability of exposure and the meaning of exposure levels and duration are also challenging to express and convey the significance to stakeholders.

D. Barrett (Office of Pesticide Programs, US EPA), M. Williams (Waterborne).  Common issues in agrochemical risk communication.  Poster, ACS 2019.  AGRO 290. San Diego, California.