Richard Brain, JiSu Bang, Jeff Perine 

# Proposals for Refining Screening Level Risk Assessments for Endangered Species; an Herbicide Example

April 22, 20142 • 1,853 co

- occurrence counties between soybean growing counties and EPA/FWS species counties

were identified.

• **52,948,707 soybean acres** (~83% of total soybean acres in US) were reported in the 1,853 counties. 

# Example of Potential Soybean Acreages

– using currently planned step 1 approach by EPA / Services3 

# Example Refinements

● Incorporation of more realistic exposure assumptions in

models

● Collation of field crop identity, field dimensions, field coordinates, and locations of listed species and habitat for use in geospatial analyses

● Biological considerations including life

- history characteristics, dietary and habitat requirements, foraging behavior, reproduction and migration timing, obligate relationships and other species

- specific biological data

● Use of community

- level effects endpoints such as species sensitivity distributions (SSDs) to estimate impacts on prey availability and habitat of listed species

● Incorporation of probabilistic techniques4 

# Estimation of Spray Drift Deposition Using REGDISP (v1.0)

● REGDISP adds 49 unique AAFC* datasets from 2000

- 2011

- 9 nozzles (air induction/chamber)

- 2 boom heights (60 cm, 90 cm)

- Wind speeds 5.9

– 20.0 mph

● Built on AGDISP v8.26 platform

- Mechanistic code unchanged

- Empirical equations for datasets processed by AGDISP calculators

- Linear regression (y = mx + b) based on log

- transformed deposition curves

*Agriculture and Agri Food Canada5 

# REGDISP Datasets Used and Model Outputs (Distances in Feet) (AAFC Datasets, Boom Height = 60 cm, Wind Speed ≤10 mph)

ASABE S

- 572.a

Spray Quality Year Nozzle DV 50 (μm) Wind Speed (mph) Lettuce EC25 1 Lettuce NOEC 2

Coarse

Spray Medium Spray Coarse Spray Medium Spray

Coarse 2000 AI110025 580 7.95

9.88 10

39 39

203

2011 AIXR110

- 025 526 7.88

9.72 16

30 62

82

Medium 2000 XR8003 257 7.71 23 105

2011 XR80

- 03 217 5.91

6.18

6.39 16

26

36 82

108

121

2004 XR8003 217 9.57 66 276

STATISTICS Median 23 26 72 108

Mean 24 33 97 138

90 th Percentile 36 54 167 214

1 Lettuce EC25 = 0.0005371 lb ai/A (lowest among 10 plant species)

2 Lettuce NOEC = 0.0000857 lb ai/A (lowest among 10 plant species)6 

# No LOC Exceedances for Aquatic Animals

0.00001 0.003 0.0002 0.00001 <0.0001 <0.0001 0.00003 0.00047 

# No LOC Exceedances for Aquatic Plants

0.003 0.0002 0.00008 0.0006 0.618 

# No LOC Exceedances for Terrestrial Animals

0.04 0.05 0.01 0.53

0.01 0.27

0.039 

# Terrestrial Plants

TERRPlant NTP RQ Values for Ground Applications Incorporating PRZM Edge of Field Runoff Flux 1

Ground Drift 2 Dry Areas 3 Semi

- Aquatic 3

Plant EC25 NOEC EC25 NOEC EC25 NOEC
**Allium cepa** (onion) 0.1 0.3 0.1 0.2 0.3 0.5

**Zea mays** (corn) 0.01 0.01 0.008 0.008 0.03 0.03

**Avena sativa** (oat) 0.01 0.01 0.04 0.1 0.1 0.4
**Lolium perenne** (ryegrass) 0.01 0.03 0.05 0.08 0.1 0.3
**Glycine max** (soybean) 0.3 0.9 0.008 0.008 0.03 0.03

**Brassica rapa** (turnip) 1.9 7.8 0.08 0.1 0.2 0.4

**Lactuca sativa** (lettuce) 3.7 23 0.8 2.2 2.6 7.0

**Cucumis sativa** (cucumber) 1.5 2.6 0.05 0.1 0.1 0.4
**Lycopersicon esculentum** (tomato) 2.3 2.6 0.1 0.2 0.4 0.5

**Brassica oleracea** (cabbage) 0.8 2.6 0.2 0.2 0.7 0.7

1 EC25 and NOEC values were used to evaluate model indicators of potential indirect and direct effects,
respectively; vegetative vigor endpoints were used for the drift scenario and seedling emergence endpoints were
used for dry areas and semi

- aquatic scenarios

2 Vegetative vigor endpoints were sourced from MRID 46562904

3 Seedling emergence endpoints were sourced from MRID 4450511910 

# Probabilistic Drift Example

Histogram of RegDisp deposition estimates at a defined distance with MLE estimated lognormal distribution (x = lb a.i./A; output from PROC UNIVARIATE in SAS Version 9.3)11 

# Probabilistic Drift Example

SSD models fit to log transformed dry weight ER25s from the vegetative vigor study (e.g. OCSPP 850.4150)12 

# Probabilistic Drift Example13 

# Geospatial Analysis (Species Data)

● FESTF Aggregated Species Database

- 2013 IMS Database

• Aggregated county

- level species location database from various

sources

- 2013 MJD Spatial Data

• Element Occurrence (EO) data (sub

- county level location data) 

## US FWS

NMFS

Nature Serve

US EPA14 

# Geospatial Analysis (Species Data)

● Critical Habitat Data

- U.S. FWS data were downloaded from the Critical Habitat (CH) Portal

- For species for which the spatial data for their Critical Habitats are not available in the Portal, spatial data was digitized based on the Federal Register (FR)15 

# Geospatial Analysis (Land cover data)

● Sub

- county level analyses conducted using three land cover data development approaches

1. NLCD 2006 class 82 (cultivated cropland)

2. 5

- year (2008

- 2012) soybean composite constructed from the NASS CDL

- CDL Classes 5 (Soybeans), 239 (Dbl Crop Soybeans/Cotton), 240 (Dbl Crop Soybeans/Oats), and 254 (Dbl. Crop Barley/Soybeans) were included to develop soybean footprint data



## 3. Probabilistic land cover approach

- Refined land cover data developed by varying degrees of certainty or uncertainty of crop occurrence in a given location using multi

- data layers weighted based on frequency, data quality and resolution (under the methodology development)16 

# Probabilistic Geospatial Analysis (Land cover)17 

# Geospatial Analysis

● Consideration of registration area: Continental U.S. only

● Co

- occurrence/proximity analyses

1. County

- level co

- occurrence analysis performed with species county database and soybean growing counties from Ag Census

2. Subcounty

- level proximity analysis (where EO data is available)

 Historical EOs were not included in the analysis: observed in Pre

- 1980 or recorded as “Extirpated” or “Historical” (21 % of total number of EOs in MJD database are historic records)

 Distances between EO and soybean footprint data were used to identify known species locations (EOs) found within potential use areas including off

- target use areas.



## 3. County

- level analysis (if a habitat location is reported in the database from EPA/FWS/NMFS/ NS MJD; but where spatial data for EOs are not available)

 Biological considerations (taxonomic comparison)18 

# Taxonomic Comparison (An Example of Biological Considerations)

● Prairie Bush Clover ( Lespedeza leptostachya )

- According to FESTF aggregated species database, this species has potential habitats and known occurrences found in the major soybean growing counties of IA, IL, WI and MN (~14% of total soybean acres in US).

- Prairie Bush Clover is a member of the pea family and the taxonomic comparison was considered.19 

# Taxonomic Considerations?

● Case Study: Prairie bush

- clover (Dicot taxonomic comparison)

Species Common

Name Subclass Order Family Genus Species

Soybean Rosidae Fabales Fabaceae Pea family Glycine Willd. Glycine max (L.) Merr.

Prairie Bush
Clover Rosidae Fabales Fabaceae Pea family Lespedeza Michx. Lespedeza leptostachya Engelm.

Garden lettuce Asteridae Asterales Asteraceae Aster family Lactuca L. Lactuca sativa L.

TERRPlant NTP RQ Values for Ground Applications Incorporating PRZM Edge of Field Runoff Flux

Ground Drift Dry Areas Semi

- Aquatic

Plant EC25 NOEC EC25 NOEC EC25 NOEC
**Glycine max** (soybean) 0.3 0.9 0.008 0.008 0.03 0.03

**Lactuca sativa** (lettuce) 3.7 23 0.8 2.2 2.6 7.0



## ● Among tested species, prairie bush

- clover is most taxonomically related to soybean down to the Family level; lettuce is only related down to class

● Thus soybean is a more appropriate surrogate species than lettuce

● Given the NLAA conclusion for, and taxonomic relatedness to soybeans, prairie bush clover can be excluded20 

## ● Preliminary sub

- county analysis was conducted for the species county, where EO data (dicot, conifer, ferns, and lichens) were available.

● Preliminary results showed that 1,120 EOs of 70 species were identified with the potential to be within 225 ft distance of potential soybean growing areas using the soybean composite data based on

5

- year NASS CDLs

. 

# Preliminary Results from Geospatial Analysis (Subcounty

- level proximity analysis where the EO data available)

Distance (ft) NLCD 2006, Class 82 (Number of Terrestrial

Non

- Monocot Plant Species) 2008

- 2012 CDL (Number of Terrestrial

Non

- Monocot Plant Species)

0 144 63

<= 225* 165 70

* From the REGDISP modeling based on Lettuce NOEC described in Slide 5 

## Number of species overlapped with land cover data21 

# Preliminary Results from Geospatial Analysis (An example of Probabilistic Approach)

Data Source: Hypothetical EO shown for mapping purpose only due to data confidentiality 

## • Probabilistic analysis showed that > 20% of 1,120 EOs represented <0.1% probability of soybean occurrence within the EO area.22 

# Preliminary Results from Geospatial Analysis (County

- level analysis for a county is reported as the species habitat; but EO data are not available)



## ● Spatial analyses showed that a total of 86 terrestrial non

- monocot plant species co

- occurred with soybean growing areas; EO data were available for 70 species, but 30 of the 70 species were double

- counted
from both EO and non

- EO analyses.

● Considerations for refinements

- Biological considerations (i.e. taxonomic

comparison).

- Additional species data sources

• State Natural Heritage Programs

- No EO data for the listed terrestrial plants in NJ

- However, Natural Heritage Program data ( http://www.nj.gov/dep/gis/stateshp.html )

could be considered for a refined analysis.23 

# Example of Potential Soybean Acreages **For a species that was reported in EPA/FWS database; but no EO**
**data was available**

• 304 co

- occurrence counties between soybean growing counties and EPA/FWS species counties were

identified.

• **3,944,970 soybean acres** (~6% of total soybean acres in US) were reported in the 304 counties.24 

# Example of Potential Soybean Acreages

- where best available
science and data used

– EO data available

• 1,120 current EOs were

identified within 225 ft distance area of soybean growing areas.

• **46,081 soybean acres** (~0.07% of total soybean acres in US) were identified

within 225ft distance areas of
EOs.25 

# Questions?