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PostersWater/Wastewater Assessments2019

Modeling aquatic and terrestrial transport pathways for microplastics entering WWTP systems

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SETAC 2019, TP144
Toronto, Ontario, Canada
Session Title: Microplastics in the Environment: Transport, Fate and Ecological Effects
Tuesday, November 5, 2019
8:00 am, Exhibit Hall

Abstract:
Microplastics may enter the environment from a number of sources and in many forms. Plastic particles may be present as influent into municipal wastewater treatment plants (WWTPs). A large portion of these are removed from the water phase during the treatment process, and generally end up in the solids (i.e., sludge). Sludge disposal varies by country, region and locality, including landfill, incinerator, compost, or as land-applied biosolids. There is potential for particles in biosolid applications to reach aquatic systems depending on application location and subsequent environmental conditions. We present a broad-scale model designed to estimate emissions and model the fate of plastic particles exiting WWTPs into the terrestrial and aquatic environments, using spatially-explicit information on WWTPs, river hydrology and terrestrial transport potential. This regional/continental scale model is based on publicly available datasets and contained in a modular and transparent framework which is scalable and portable to multiple geographies. This presentation will demonstrate the utility of the model as applied to different regions, and how the resulting information about ultimate mass disposition within the environment (e.g., soil, freshwater, sediment, marine) and surface water concentrations can be examined to help inform the discussion about prospectively assessing the presence and concentration of microplastic particles in the environment as emitted by WWTPs.

C. Holmes (Applied Analysis Solutions), J. Amos (Waterborne), S. Dyer (Waterborne). Modeling aquatic and terrestrial transport pathways for microplastics entering WWTP systems. Poster, SETAC 2019. TP144. Toronto, Ontario, Canada.

PresentationsHome and Personal Care Products, Water/Wastewater Assessments2019

Development of integrated risk assessment framework and methodology for assessing environmental safety of chemicals disposed down the drain in China

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SETAC 2019, Platform 30
Toronto, Ontario, Canada
Session Title: Building Bridges Between Lab-and Field-Derived Data: Methods for the Assessment of Complex Environmental Issues
Monday, November 4, 2019
10:40 am, Room 717B

Abstract:
The new Chinese regulatory chemical management scheme calls for increased development of risk-based assessment framework and tools that can address regional and national needs. Important considerations include identifying chemicals with high potential for adverse impact to humans and the environment early in the assessment, while also recognizing regional differences in the levels of economic and infrastructure development as well as environmental conditions. An integrated, tiered environmental risk assessment framework and methodology was developed for assessing the environmental safety of chemicals disposed down the drain in China. The tiers incorporate China’s specific exposure conditions as well as consideration of Chinese native species for effects assessment. The framework starts with a Low Tier utilizing the existing Chinese regulatory qualitative method, whereas Mid-Tier is quantitative using deterministic and probabilistic approaches that account for per capita residential water usage, wastewater treatment capability, as well as wastewater/in-stream dilution factors. A High Tier spatially explicit aquatic exposure model was recently created which leveraged historic work on the iSTREEM® model (American Cleaning Institute). A high-resolution river flow dataset was established based on the Curve Number method (Natural Resources Conservation Service, U.S. Department of Agriculture) and further validated by monitoring data. Case studies will be presented for consumer product ingredients which indicate Lower Tiers are conservative with greater environmental realism associated with High Tier methodology. A key aspect for the integrated framework is environmental effects assessment based on Chinese native species, as chemical registrations in China routinely involve local fish testing. The Chinese Rare Minnow (Gobiocypris rarus) and Chinese Medaka (Oryzias sinensis) are examples of leading local species. This research developed an understanding of the ecology, physiology, and other biological information allowed for the extrapolation between these two species and other OECD standard test species (e.g., zebrafish). We investigated comparative fish acute toxicity using 3,4-Dichloroaniline and NaCl with studies planned on additional chemicals and species. Chinese native species data will be utilized not only for direct hazard assessment but also for the development of statistical extrapolation methods, such as interspecies correlation estimation (ICE) models. ICE models use available toxicity data of surrogate species to predict untested species to expand the domains of ecotoxicological information for China’s integrated environmental risk assessments.

M. Fan (P&G), K. McDonough (P&G), S. Belanger (P&G), Z. Liu (Chinese Research Academy of Environmental Sciences), R. Vamshi (Waterborne), S. Csiszar (P&G), J. Menzies (P&G), X. Wang (Chinese Research Academy of Environmental Sciences), K. Kapo (Waterborne).  Development of integrated risk assessment framework and methodology for assessing environmental safety of chemicals disposed down the drain in China. Platform 30, SETAC 2019. Toronto, Ontario, Canada.

PresentationsWater/Wastewater Assessments2019

High-Resolution Global Mean-Annual Surface Runoff And River Flow Datasets For Use In Risk Assessments

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SETAC 2019, Platform 50
Toronto, Ontario, Canada
Session Title: Challenges in Characterizing Exposures to Organic Chemicals: Multiple Sources, Multiple Pathways and Multiple Scales
Monday, November 4, 2019
8:40 am, Room 716B

Abstract:
The availability of detailed surface runoff and river flow data across large geographic areas is crucial for modeling in ecological risk assessments; a few countries (e.g., U.S.) offer such data at a high-resolution and most countries do not. Lack of detailed spatial data and challenges with intense processing have been the limiting factors in developing high-resolution river flows over large spatial scales. iSTREEM®, a broad-scale spatial model in the U.S. incorporates a detailed hydrology network with river flows from the NHDPlus to estimate exposure across large areas from the use of down-the-drain chemicals. It combines WWTP emissions into corresponding flow at receiving rivers to estimate dilution factors and down-the-drain chemical concentrations, and route them through the river network. A similar approach to integrate chemical emissions with a global hydrologic river network and associated flows can be employed to estimate local dilution factors and chemical concentrations across river network over countries where environmental concerns are a high priority. To address this specific need, the well-established Curve Number (CN) method was applied to develop a detailed surface runoff dataset. Publicly available, scientifically accepted and high-resolution global datasets for hydrologic soil groups, land cover, and precipitation were spatially processed by applying the CN equations to generate a contiguous global mean-annual surface runoff grid at a very high-resolution of 50m x 50m. Surface runoff was converted to river flow by spatially combining with a detailed global hydrology of rivers and catchment boundaries from HydroSHEDS and HydroBASINS to estimate mean-annual flows across the global river network. Evaluation of the estimated river flow was conducted against publicly available gage measurements in China and river flows in the Ohio River basin, U.S.; both showed high correlation (r2 = 0.70 for China and 0.97 for Ohio River). Applying the detailed global mean-annual river flows with broad-scale environmental exposure models like iSTREEM® provides a robust approach to assess ecological risk of chemicals used in home and personal care products, cosmetics, pharmaceuticals, etc. over large river basins, across a country, or at a continental scale.

R. Vamshi (Waterborne), K. McDonough (P&G), K. Stanton (ACI), A. Ritter (Waterborne).  High-Resolution Global Mean-Annual Surface Runoff And River Flow Datasets For Use In Risk Assessments. Poster, SETAC 2019. Platform 50. Toronto, Ontario, Canada.

PostersHome and Personal Care Products, Water/Wastewater Assessments2019

Moving toward a spatially-resolved global surface water flow and aquatic exposure model for consumer-use down-the-drain ingredients: Japan case study

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SETAC 2019, MP123
Toronto, Ontario, Canada
Session Title: Challenges in Characterizing Exposures to Organic Chemicals: Multiple Sources, Multiple Pathways and Multiple Scales
Monday, November 4, 2019
8:00 am, Exhibit Hall

Abstract:
Exposure assessment is a key factor in the environmental risk assessment (ERA) of consumer products that are disposed down-the-drain and involves estimating concentrations of ingredients in receiving waters. There is an opportunity to develop a globally-harmonized spatially explicit aquatic exposure model for down-the-drain ingredients by leveraging the growing availability of computational methods and large spatial datasets. Current models often assume average conditions across a country/region in a deterministic calculation, while, in reality, there can be substantial spatial variation in input parameters (e.g., emissions, per capita water use, and waste water treatment) across a region. While spatial variability has been addressed by some models, they have focused on a single country/region; and there is a need for a user-friendly, global aquatic exposure model on a single platform with a consistent approach, using best available data. The iSTREEM® model (American Cleaning Institute) is a spatially-explicit aquatic exposure model parameterized and evaluated primarily for the United States. The model has also been extended to China and evaluation has indicated excellent agreement between modeled and measured river flow data. There was also excellent agreement between case study modeled and monitored chemical concentrations. This platform was leveraged and extended to cover Japan and follows a framework that uses global datasets to estimate river flow on a catchment level, rout chemicals between catchments, and estimate catchment-specific concentrations. Each catchment is parameterized with a specific population, per capita water use, and waste water treatment plant (WWTP) information; and allows for spatial variation in emissions. For Japan, spatial locations of WWTPs were incorporated into the model and the resulting population served by WWTP treatment corresponds well with published reports of treatment levels. Direct discharge of grey water was included to represent current practice in some areas of Japan. Measured river flow data and case study chemicals with available monitoring data were used to evaluate the flow predictions and concentration distributions estimated by the model. Thus, this model framework provides a promising platform for expansion as a global aquatic exposure model for down-the-drain ingredients.

S. Csiszar (P&G), R. Vamshi (Waterborne), M. Fan (P&G), K. McDonough (P&G).  Moving toward a spatially-resolved global surface water flow and aquatic exposure model for consumer-use down-the-drain ingredients: Japan case study. Poster, SETAC 2019. MP123. 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.

PresentationsCrop Protection

Effect of the VFSMOD pesticide trapping equation on environmental exposure assessments

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ACS 2019, AGRO 136
San Diego, California
Session Title: Off-Target Transport of Field Applied Agricultural Chemicals:  Study Designs, Monitoring, Modelling, & Risk Assessment
Monday, August 26, 2019
3:05 pm, Ballroom 20B-D, Theater 5

Abstract:

Vegetative filter strips (VFS) are a common land management practice aimed at limiting sediment, nutrient, and pesticide runoff from reaching adjacent surface water bodies. Recently, VFS have been included on label requirements for several pesticides produced in the United States and Europe. However, questions still exist regarding the ability to accurately predict pesticide trapping efficiencies across a range of conditions and how to incorporate predictions of pesticide trapping into environmental exposure assessments. More specifically, the role of VFS in limiting pesticide transport to surface water bodies has yet to be widely implemented as part of the higher-tier risk assessment process in Europe or the United States.
Previous research has proposed a modeling framework that links the U.S. Environmental Protection Agency’s (US-EPA) PWC model (PRZM/VVWM) with a well-tested process-based model for VFS (VFSMOD). The original pesticide trapping efficiency was based on a regression equation based on integrated mechanisms of infiltration and sediment trapping along with factors that accounted for the distribution of pesticide between the solid and dissolved phases and percent clay (Sabbagh equation). Recently, three new pesticide trapping efficiency equations have been developed: two regression-based (reparameterized Sabbagh and Chen) and one mechanistic (mass balance approach). There is still a need to determine the relative importance of the type of trapping equation used within environmental exposure assessments. An analysis of the pesticide trapping efficiency applying the four equations with three US-EPA standard scenarios (California tomato, Illinois corn, and Oregon wheat) will be presented. Such an analysis will provide key information on the impact of the selection of a specific trapping efficiency equation for higher-tier pesticide exposure assessments. Such results will provide a significant piece of information as regulatory agencies across the globe consider how to incorporate the influence of VFS into pesticide risk assessments

R. Munoz-Carpena (University of Florida), G. Fox (North Carolina State University), A. Ritter (Waterborne).  Effect of the VFSMOD pesticide trapping equation on environmental exposure assessments.  Presentation, ACS 2019.  AGRO 136. San Diego, California.

PresentationsCrop Protection2019

Multi-year field studies evaluating the benefits of vegetative filter strips

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ACS 2019, AGRO 134
San Diego, California
Session Title: Off-Target Transport of Field Applied Agricultural Chemicals:  Study Designs, Monitoring, Modelling, & Risk Assessment
Monday, August 26, 2019
1:55 pm, Ballroom 20B-D, Theater 5

Abstract:

Off-target agricultural chemical transport to surface water has been studied under USEPA Good Laboratory Practice Standards for many years to support environmental risk assessment. Field-scale runoff studies provide real-world data to understand the potential environmental exposure, resulting from runoff or erosion of agricultural chemicals. A multi-year field scale runoff study was designed to evaluate vegetative filter strip (VFS) performance under natural rainfall conditions in Missouri, under a corn/soybean crop rotation. The study consists of nine runoff plots with varying, replicated VFSs widths (3 plots each of: 0ft, 15ft, and 30ft). Additionally, plots were instrumented to facilitate future modeling. The runoff collection programming was designed with adherence to NRCS Edge-of-Field Monitoring System Guidance. Design complexities including unattended, refrigerated, runoff sample collection for a multi-year study under natural rainfall conditions will be discussed, and initial data collected from the treatments will be presented.

A. Ritter, F. Abi-Akar, P. Paulausky, G. Goodwin, J. Trask, L. Carver, M. Cox (Waterborne), A. Moore, C. Truman (Syngenta).  Multi-year field studies evaluating the benefits of vegetative filter strips.  Presentation, ACS 2019.  AGRO 134. San Diego, California.