Dat e:

S ubj ect: 

### UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON

, D.C

. 20460

Marc h 29, 2016 OFFICE OF CHEMICAL SAFETY

AND POLLUTION PREVENTION

Dicamba. Occupat i ona l and Reside nti al Exposure Assessment for a Prop osed

Use o n Herbicide-Tolerant Soybean and Cotton

P C Co d e: 02980 I (acid), 128931 (DGA salt)

, I 00094 (BAPMA salt)

D ec i sio n No.: 4637 10 DP B a r co d e : 0429870 Registration No.: 524-582

R eg ul atory Action: Section 3

Case No.: NA P e titi o n No.: NA

Ri s k A ssess m e nt Type: Occupational/ R es id e ntial Expos ur e Asse ss ment
T XR No

. : NA CAS No.: 1918

- 00-9

, I 04040- 79-1

.t O CF R : 180.227 MR ID No. : NA



### From:

Throug h:

To:

Intr oduct i on ,-...._,

Alexandra Gavclek

, Biol og ist 

# / A, {) 

# Ii

- 

# +6\

Kelly M. Lowe

, E n v i ro nm e nt a l

# Jc**en ti** **......_ ,.** **,..... ~~**  Risk Assessment Branch V 

### N II

- 

## 0

-

Health Effec ts Division (7509 P)

# ~**~f.J** 

# )

. I

# ~

Michael Metzger, Branch Chief 

# V \\.

Risk Assessment Branch V N II

H ea l th Effects D i vis ion (7509 P )

a nd

Matthew Crowley /(

# .,, Cassi Walls 

# WT**u~** Expos ur e Scie n ce Advisory Committee (Ex po SAC) 

### I H ED

Kathr yn Monta g ue Reg i s trati o n Di v i s ion (7505P)

T h e R egis trati on Division (RD) r eq u es t ed that the He a lth Effec t s Di v i sion (HE D ) co ndu c t a n occupational and residential exposure and risk assessment for the proposed new u se of the dig l yco lamine ( DGA ) sa lt of dicamba on dicamba-to l erant cotton and soybean, as well as for the

propo se d new BAPMA sa lt of dicamba for u se o n conven t ional cro p s, in c l uding di cambatolerant crops.

Page I of 36

### lt i s H ED policy t o use the best available data to a ssess exposu r e. Several sources of generic

d a ta were used in this assessment as su rro gate dat a in the absence of c h e mi c al- s pe c ific data

, includin g P est icid e H and l e r s Exposure Dat abase Vers i on I. I ( PH E D 1

. 1 ); th e Agricultural

Handler E xpos ur e Task Force (A HET f) database ; the Outd oo r R es id e ntial Expos ur e Ta sk Fo r ce (O R ET F) databas e; the Ag ri cultural R ee ntr y Task Force (A RTF) dat abase; a nd th e Re s id e ntial

SO P s

. So m e of these d a t a are proprietary

, and s ubj ec t to the d a t a protection provisions of the

federal Ins ec ticid e, Fun g icide

, a nd R ode nti c ide Ac t (FIFRA).

Note: 

### This mem ora ndum was reviewed b y th e Exposure Sc i e n ce Adv i so r y Co mmitt ee (Ex po SAC) on Oct o ber 29, 20 1 5.

Page 2 of 36Page 3 of 36 

### Table of Contents

1.0 Executive Summary

................................ ................................ ................................ ............. 4

2.0 Risk Assessment Conclusions and Recommendations

................................ ........................ 5

2.1 Data Deficiencies and Requirements

................................ ................................ ............... 6

3.0 Hazard Characterization

................................ ................................ ................................ ....... 6

4. 0 Use Profile

................................ ................................ ................................ ........................... 8

5.0 Residential Exposure and Risk Estimates

................................ ................................ .......... 12

5.1 Residential Handler Exposure/Risk Estimates

................................ ............................... 12

5.2 Residential Post

- application Exposure/Risk Estimates

................................ .................. 14

5.3 Residential Risk Estimates for Use in Aggregate Assessment

................................ ...... 18

6.0 Non

- Occupational Spray Drift Exp osure and Risk Estimates

................................ ................ 19

7.0 Non

- Occupational Bystander Post

- Application Inhalation Exposure and Risk Estimates

..... 21

7.1 Flux Data

................................ ................................ ................................ ........................ 21

7.2 Volatilization Modeling and Risk Assessment

................................ .............................. 22

7.3 Volatilization Risk Estimates

................................ ................................ ......................... 23 8.0 Occupational Exposure and Risk Estimates

................................ ................................ ........... 23 8.1 Occupational Handler Exposure/Risk Estimates

................................ ................................ 23

8.2 Occupational Post

- application Exposure/Risk Estimates

................................ .............. 27

8.2.1 Occupational Post

- application Inhalation Exposure/Risk Estimates

...................... 27

8.2.2 Occupational Post

- ap plication Dermal Exposure/Risk Estimates

.......................... 28 Appendix A. Summary of Occupational and Residential Non

- cancer Algorithms

..................... 29Page 4 of 36



### 1.0 Executive Summary

The Registration Division (RD) requested that the Health Effects Division (HED) conduct an exposure and risk assessment for a proposed new use of the diglycolamine (DGA) salt of

dicamba and the new N, N

- Bis

- (3

- aminopropyl) methylamine (BAPMA) salt of dicamba on dicamba

- tolerant cotton and soybean

. The new dicamba BAPMA salt is also proposed for use on several agricultural crops in addition to dicamba

- tolerant cotton and soybean. The dicamba DGA

salt pr oduct, M1691 Herbicide, is formulated as a liquid concentrate and contains 56.8% active ingredient diglycolamine salt of dicamba (38.5% dicamba acid, or 4 lbs acid equivalent (ae) per gallon). The dicamba BAPMA salt product, Eng e nia® Herbicide, is formula ted as a liquid concentrate and contains 60.8% active ingredient N,N

- Bis

- (3

- aminopropyl)methylamine salt of 3,6

- dichlor o

- o

- anisic acid (48.38% dicamba acid, or 5 pounds acid equivalent per gallon). The

label for the DGA salt of dicamba states that mixers, loaders, applicators

, and other handlers

must wear required work attire and chemical

- resistant gloves (except for applicators using groundboom equipment, pilots or flaggers). The label for the BAPMA salt of dicamba lists required work attire and no person al protective equipment (PPE) for all handler activities. The restricted entry interval (REI) on the proposed label s is 24 hours.

Occupational handler and post

- application exposures are anticipated from the proposed uses of dicamba on cotton and soybean , as well as the proposed use of dicamba BAPMA salt on various agricultural crops. No residential exposures are anticipated from the proposed uses; however, there are existing residential turf uses of dicamba that have been reassessed here to reflect upda tes to the 2012 Residential SOPs. Non

- occupational exposures from spray drift and bystander volatilization have also been addressed for both dicamba and the BAPMA salt

.

For both dicamba and the BAPMA salt, no dermal assessment was conducted since the d ermal toxicology studies all had no observed adverse effect levels (NOAELs) of 1000 mg/kg/day. The point of departure (POD) for the inhalation route for dicamba was chosen from an inhalation study in rats with dicamba acid, with a NOAEL of 0.005 mg/L. Th e POD for the inhalation route for the BAPMA salt was chosen from an inhalation study with BAPMA, with a lowest observed adverse effect level (LOAEL) of 0.0014 mg/L. For both dicamba and BAPMA salt, a

POD for the incidental oral route was chosen from a re productive study in rats with dicamba acid, with a NOAEL of 136 mg/kg/day.

There are no proposed residential uses at this time for either dicamba or the BAPMA salt ; however, there are existing residential turf uses of dicamba that have been reassessed i n this document to reflect updates to HED’s 2012 Residential Standard Operating Procedures ( SOPs ). The residential handler and post

- application risk estimates are not of concern for dicamba for all scenarios and all routes of exposure (i.e., all inhalation MOEs ≥ 30 and all incidental oral MOEs ≥ 100)

.

A quantitative assessment of exposure and risk resulting from spray drift was conducted for the BAPMA salt, which results in no risk estimates of concern (i.e., all MOEs ≥ 100) at the field edge for aerial and groundboom applications at the maximum agricultural application rate of 1 lb

ae/A. Since the dicamba residential turf application rate is equal to or higher than the proposedPage 5 of 36



### uses of dicamba on agricultural crops, the residentia l turf scenario is protective of any exposure via spray drift from the proposed agricultural dicamba applications.

The potential non

- occupational exposure to vapor phase dicamba and BAPMA residues emitted from treated fields from the proposed uses has bee n evaluated in this assessment. Volatilization modeling was completed using Probabilistic Exposure and Risk model for FUMigants ( PERFUM) as well as chemical

- and formulation

- specific flux data. The results indicate that

volatilization of dicamba and BAPM A from treated crops does occur and could result in bystander exposure ; however, results of PERFUM modeling indicate that airborne concentrations, even at the edge of the treated fields, are not of concern.

There is no potential hazard via the dermal ro ute for dicamba ; therefore, only a quantitative inhalation exposure and risk assessment was completed for occupational handlers. The occupational handler inhalation risk estimates are not of concern for dicamba DGA salt (i.e., MOEs ≥ 30) . Most occupation al handler inhalation risk estimates are of concern for dicamba

BAPMA salt (inhalation MOEs < LOC of 300) based on the label

- required PPE (i.e., no respiratory protection). Some handler risk estimates are of concern despite assuming maximum respiratory protection/ engineering controls.

Since t here is no potential hazard via the dermal route for dicamba

, a quantitative occupational
post

- application dermal risk assessment was not completed. The REI on the proposed labels is based on WPS requirements (24 hours). Based on the Agency's current practices, a quantitative

non

- cancer post

- application inhalation exposure assessment was not performed for dicamba at this time. If new policies or procedures are put into place, the Agency may revisit the need for a quantitative occupational post

- application inhalation exposure assessment for dicamba

.

Human Studies Review

This risk assessment relies in part on data from studies in which adult human subjects were intentionally exposed to a pesticide or other chemic al. These data, which include studies from PHED 1.1; the AHETF database; the ORETF database; the ARTF database; and the Residential

SOPs , are (1) subject to ethics review pursuant to 40 CFR 26, (2) have received that review, and (3) are compliant with app licable ethics requirements. For certain studies, the ethics review may have included review by the Human Studies Review Board. Descriptions of data sources, as well as guidance on their use, can be found at the Agency website 1



### .

2.0 Risk Assessment Conclusions and Recommendations

There are no proposed residential uses at this time; however, the existing residential uses for

dicamba were reassessed. There were no residential risk estimates of concern for the uses of

dicamba

.

The occupational handler inhalation risk estimates are not of concern for DGA salt of dicamba (i.e., MOEs ≥ 30) . Most occupational handler inhalation risk estimates are of concern for

1 http://www2.epa.gov/pesticide

- science

- and

- assessing

- pesticide

- risks/occupational

- pesticide

- handler

- exposure

- data and http://www2.epa.gov/pesticide

- science

- and

- assessing

- pesticide

- risks/occupational

- pesticide

- post

- application

- exposurePage 6 of 36



### dicamba BAPMA salt (inhalation MOEs < LOC of 300) assuming the label

- required PPE (i.e., no respiratory protection). Some occupational handler risk estimates are of concern despite assuming maximum respiratory protection/ engineering controls.

No quantitative post

- application dermal assessment was conducted since a dermal hazard was

not i dentified; therefore, t he REI on the proposed label is based on the minimum Worker Protection Standard ( WPS ) requirements (24 hours)

.

2. 1 Data Deficiencies and Requirements

None.

3 .0 Hazard Characterization

Acute Toxicity

A summary of the acute toxicity data is included in Table 3.0.1. Dicamba is Acute Toxicity Category III or IV via the oral, inhalation or dermal routes of exposure. Dicamba is an eye and skin irritant (Toxicity Category II), however, it is not a skin sensitizer.

Table 3.0.1 Acute Toxicity of Dicamba

Guideline

No. Study Type MRID NO. Results Toxicity Category

870.1100

870.1200

870.1300

870.2400

870.2500

870.2600 Acute Oral

Acute Dermal

Acute Inhalation Primary Eye Irritation Primary Skin Irritation

Dermal sensitization 00078444

00241584

00263861

00241584

00237955

00263861 LD 50 = 2740 mg/kg

LD 50 > 2000 mg/kg

LC 50 = >5.3 mg/L

Irritant

Irritant

Non sensitizer III

III

IV

II

II

N/A



### Toxicological PODs Used for Risk Assessment

The toxicological endpoints used to complete residential and occupational exposure assessments

are summarized in Table 3.0.2 (Dicamba DGA salt) and 3.0.3 (Dicamba BAPMA salt)

. HED recommends that the 10X FQPA Safety Factor (for the protection of infants a nd children) be

reduced to 1X for all scenarios, except for the inhalation scenario for dicamba BAPMA salt

which will have a 10X UF L 

### retained for lack of a NOAEL in the inhalation study.Page 7 of 36

Table 3.0.2 Toxicological Doses and Endpoints for Dicamba DGA Salt / Dicamba Acid for use in Human

Health Risk Assessments

Exposure

Scenario Point of Departure FQPA SF and Level of

Concern for Risk

Assessment Study and Toxicological Effects

Acute Dietary (Used for Granule Ingestion Assessment) (General population including infants and

children NOAEL = 29

mg/kg/day

Acute RfD = 0.29 mg/kg/day UF A =10x

UF H =10x

FQPA SF = 1X

aPAD = 0.29 mg/kg/day Dicamba BAPMA Rat Developmental Study

Maternal NOAEL is 29 mg/kg/day in dams (20 as Acid form)

LOAEL is 86 mg/kg/day in dams, based on ataxia, unsteady gait and convulsions (60 as Acid Form)

Developmental NOAEL > 288 mg/kg/day (200 as acid equivalent)

Short

- (1

- 30 Days)

and Intermediate

- (1

- 6 months) Term

Incidental Oral Offspring NOAEL=

136 mg/kg/day UF A =10x

UF H =10x

FQPA SF = 1X

LOC for MOE = 100 Reproductive study in rats with

Dicamba Acid

. Offspring LOAEL=450 mg/kg/day based on decreased pup weights.

No dermal assessment for dicamba acid since the dermal toxicology studies for dicamba acid, IPA and DGA salts all had NOAELs of 1000 mg/kg/day

Short

- , Intermediate

and Long

- Term

Inhalation NOAEL=0.005/0.005

mg/L (M/F)

Residential Handler

HED=0.084 mg/kg/day HEC=0.00295 mg/L Residential Bystander HEC=0.00053 mg/L Occupational Handler

HED=0.21 mg/kg/day HEC=0.00221 mg/L UF A =3x

UF H =10x

FQPA SF = 1X

LOC for MOE = 30 Inhalation study in rats with Dicamba

Acid

.

NOAEL=0.005/0.005 mg/L (M/F) LOAEL=0.050/0.050 mg/L (M/F), based

on minimal multifocal bronchiole

- alveolar hyperplasia in males; multiple microscopic findings in the lung and associated lymph nodes in females

Cancer (Oral, dermal, inhalation) Dicamba is classified as “not likely to be carcinogenic to humans”.

Point of Departure (POD) = A data point or an estimated point that is derived from observed dose

- response data and used to mark the beginning of extrapolation to determine risk associated with lower environmentally relevant human exposures. NOAEL

= no observed adverse effect level. LOAEL = lowest observed adverse effect level. UF = uncertainty factor. UF A = extrapolation from animal to human (interspecies). UF H = potential variation in sensitivity among members of the human population (intraspecies). FQPA SF = FQPA Safety Factor . PAD = population adjusted dose (a = acute, c = chronic). RfD = reference dose. MOE = margin of exposure. LOC = level of concern. N/A = not applicable.Page 8 of 36

Table 3.0.3 Toxicological Doses and Endpoints for Dicamba BAPMA Salt for use in Human Health R isk

Assessments

Exposure

Scenario Point of Departure FQPA SF and Level of

Concern for Risk

Assessment Study and Toxicological Effects

Short

- (1

- 30 Days)

and Intermediate

- (1

- 6 months) Term

Incidental Oral NOAEL= 136 mg/kg/day UF A =10x

UF H =10x

FQPA SF = 1X

LOC for MOE = 100 Reproductive study in rats with

Dicamba Acid

.

Offspring LOAEL=450 mg/kg/day based on decreased pup weights.

No de rmal assessment for the dicamba BAPMA salt since the dermal toxicology studies for dicamba acid, IPA and DGA salts all had NOAELs of 1000 mg/kg/day

. The dicamba anion component is ~80% of the dicamba BAPMA salt weight, so the BAPMA composition is unlikely to significantly influence a dermal study toxicity if this study was performed. The acute dermal toxicity for the BAPMA salt was category IV.

Short

- , Intermediate

and Long

- Term

Inhalation LOAEL = 0.0014 mg/L

Occupational Handler

HED=0.020 mg/kg/day HEC=0.0002 mg/L

Residential Bystander

HEC=0.00005 mg/L UF A =3x

UF H =10x

UF L = 10X

FQPA SF = 1X

LOC for MOE = 300 Dicamba BAPMA Rat Inhalation Study

NOAEL=NA LOAEL=0.0014 mg/L (LDT), based

on ulcers in epithelial tissues of the larynx and single/multi

- focal hyperplasia in the larynx

Cancer (Oral, dermal, inhalation) Dicamba is classified as “not likely to be carcinogenic to humans”.

Point of Departure (POD) = A data point or an estimated point that is derived from observed dose

- response data and used to mark the beginning of extrap olation to determine risk associated with lower environmentally relevant human exposures. NOAEL = no observed adverse effect level. LOAEL = lowest observed adverse effect level. UF = uncertainty factor. UF A = extrapolation from animal to human (intersp ecies). UF H = potential variation in sensitivity among members of the human population (intraspecies). UF L = use of a LOAEL to extrapolate a NOAEL. FQPA SF = FQPA Safety Factor. PAD = population adjusted dose (a = acute, c = chronic). RfD = reference dose. MOE = margin of exposure. LOC = level of concern. N/A = not applicable.



### Body Weight

Since the inhalation PODs are not based on developmental and/or fetal effects, the body weight appropriate for inhalation assessments for adults is 80 kg. The bo dy weight for children 1 to <2 years old is 11 kg.

4 .0 Use Profile

A summary of use directions for the proposed uses of the DGA salt of dicamba are listed in Table 4.1 below. M1691 Herbicide contains 56.8% Dicamba DGA salt (38.5% dicamba, or 4 lb ae/gal). The REI on the proposed label is 24 hours and the PPE requirements are that all mixers, loaders, applicators and other handlers must wear long

- sleeved shirt and long pants, chemical

resistant gloves, and shoes plus socks (no respiratory protection).Page 9 of 36

Table 4 .1. Summary of Directions for New Use of Dicamba DGA salt (EPA Reg. No. 524

- 582)

.

Applic. Timing, Type, and Equip. Formulation Applic. Rate (lb

ae /A) M ax.

Seasonal Applic. Rate (lb ae /A) Use Directions and Limitations

Roundup Ready® 2 Xtend Soybean

Pre

- plant, At

- planting,

pre

- emergence applications

Ground Equipment Only (Aerial Application Prohibited) M1691

Herbicide

56.8%

Dicamba

DGA salt

(38.5% dicamba, 4 lb ae/gal) 1 1 The maximum combined quantity of this product that may be applied for all pre

- plant,

at

- planting, and pre

- emergence applications is

1 lb ae/acre per season
The maximum application rate for a single,

pre

- plant, at

- planting or pre

- emergence application must not exceed 1 lb ae/acre

Post

- emergence (in

crop) applications (emergence to R1 stage soybean)
Ground equipment only

(Aerial Applicat ion Prohibited) 0.5 1 Total of all in

- crop applications from emergence to beginning bloom (R1) stage soybean is 1 lb ae/acre
The maximum rate for any single, in

- crop application must not exceed 0.5 lb ae/acre

Other restrictions:
Do not apply this product to Roundup Ready® 2 Xtend Soybean using aerial spray equipment
Combined total per year for all applications maximum application rate is 2 lb ae/acre

MON 88701 Cotton

Pre

- plant, At

- planting,

pre

- emergence applications

Ground equipment Only M1691

Herbicide

56.8%

Dicamba

DGA salt

(38.5% dicamba, 4 lb ae/gal) 1 1 The maximum rate for all pre

- plant, at

planting, and pre

- emergence applications is 1

lb ae/acre per season
The maximum application rate for a single,

pre

- plant, at

- pl anting, or pre

- emergence application must not exceed 1 lb ae/acre

Post

- emergence (in

crop) (emergence to 7 days pre

- harvest)

Ground equipment Only 0.5 2 Total of all in

- crop applications application

rate is 2 lb ae/acre
The maximum rate for any single, in

- crop application must not exceed 0.5 lb ae/acre

Allow at least 7 days between applications

A pre

- harvest application of this product may be made up to 7 days before harvest

Other restrictions:

Do not apply this product to MON 88701 Cotton using aerial spray equipment
Combined total per year for all applications maximum application rate is 2 lb ae/acre



### A summary of use directions for the proposed new product, Engenia® Herbicide, are listed in

Table 4.2 below. Engenia ® Herbicide contains 60.8% Dicamba BAPMA salt (48.38% dicamba, or 5 lb ae/gal). The REI on the proposed label is 24 hours and the label requirements are that all mixers, loaders, applicators and other handlers must wear long

- sleeved shirt and long pants, shoes plus socks.Page 10 of 36

Table 4.2 . Su mmary of Directions for New Use of Dicamba BAPMA salt

.

Applic. Timing, or Type Formulation Applic. Rate (lb

ae /A) M ax.

Seasonal Applic. Rate (lb ae /A) Use Directions and Limitations

Asparagus

Post

- emergence After cutting but 24

hrs before next cutting Engenia®

Herbicide 0.5 0.5 Do not apply more than 0.5 lb ae/A per year in

asparagus

Do not harvest for 24 hours after treatment

Broadcast or spot

burndown

treatment, Between Crop Application 1 2 Burndown treatment during the fallow period following crop harvest and before the following crop is planted

Conservation Reserve Program (CRP)

Preplant,

Post

- emergence Engenia®

Herbicide 1 2 Preplant or postemergence
Postemergence application may be made after seedling grasses exceed the 3

- leaf stage
Do not apply more than 1 lb ae/A per

application

Do not apply more than 2 lb ae/A per season

Corn

Preplant/ Preemergence/ Postemergence Engenia®

Herbicide 0.5 1.5 Do not apply more than 0.5 lb ae/A in a single application
Do not apply more than 1.5 lb ae/A per

cropping season

Cotton (non

- tolerant)

Preplant , Broadcast Engenia®

Herbicide 0.25 2 Do not apply more than 0.25 lb ae/A per year (single growing season)
Do not apply more than 2 lb ae/A for the combination of treatments if applying a spring preplant treatment following application of a fall preplant (postharvest) treatment

Cotton (tolerant)

Preplant/ Preemergent

Engenia®

Herbicide 1 1 Do not apply more than 1 lb ae/A in a single application bef

ore crop emergence Do not apply more than 0.5 lb ae/A in a single postemergence application
Do not apply more than a cumulative total of 2 lb ae/A postemergence over the top

Do not apply more than 2 lb ae/A per year (single growing season)

Aerial application is not allowed for preplant, preemergence, or postemergence use in

dicamba

- tolerant cotton or soybean Postemergent 0.5 2

Grass Grown for SeedPage 11 of 36

Table 4.2 . Su mmary of Directions for New Use of Dicamba BAPMA salt

.

Applic. Timing, or Type Formulation Applic. Rate (lb

ae /A) M ax.

Seasonal Applic. Rate (lb ae /A) Use Directions and Limitations

Seedling grasses/

Well

- established

grasses Engenia®

Herbicide 1 2 Do not apply more than 1 lb ae/A per application or a cumulative total of 2 lb ae/A

per season Pasture, Hay, Rangeland, and Farmstead (noncropland)

Pasture, hay, rangeland, farmstead, noncropland, cut

surface treatment,
spot treatment Engenia®

Herbicide - 1 Do not apply more than 1 lb ae/A during a growing season
Do not apply more than 0.5 lb ae/A during a growing season on small grain grown for pasture and newly seeded areas

Proso Millet

Broadcast or spot

treatment when proso millet is in the 2 to 5 leaf stage Engenia®

Herbicide 0.125 0.125 Do not apply more than 0.125 lb ae/A per

season For use only within Colorado, Nebraska, North Dakota, South Dakota, and Wyoming

Small Grain

Early season
Engenia®

Herbicide 0.125 0.125: oats

and triticale
0.375: barley

0.5: wheat Maximum use rate per application: 0.125 lb

ae/A for oats and triticale and 0.25 for barley

and wheat
Do not apply postharvest to oats or triticale Fall seeded wheat 0.25

Preharvest 0.25

Sorghum

Preplant

Engenia®

Herbicide 0.25

0.5 A preplant application up to 0.25 lb ae/A may be applied at least 14 days before planting
Up to 0.25 lb ae/A may be applied after sorghum is in the spike stage but before sorghum is 15 inches tall
Up to 0.25 lb ae/A may be applied after sorghum has reache d the soft

- dough stage
May be applied in split applications; preplant followed by postemergence or Preharvest, or postemergence following by Preharvest. Do not apply more than 0.25 lb ae/A per application or a maximum cumulative total of

0.5 lb ae/A per y ear Postemergence 0.25

Preharvest 0.25

Soybean (non

- tolerant)

Preplant Engenia®

Herbicide 0.5

2 Do not apply more than 0.5 lb ae/A in a spring application before planting
Do not apply more than 2 lb ae/A per year (single growing season) Preharvest 1

Dicamba

- tolerant Soybean

Preplant/ Preemergent Engenia®

Herbicide 1 1 Do not apply more than 1 lb ae/A in a single application before crop emergence
Do not apply more than 0.5 lb ae/A in a single postemergence application Postemergent

– Prior to first bloom growth stage 0.5 1Page 12 of 36

Table 4.2 . Su mmary of Directions for New Use of Dicamba BAPMA salt

.

Applic. Timing, or Type Formulation Applic. Rate (lb

ae /A) M ax.

Seasonal Applic. Rate (lb ae /A) Use Directions and Limitations

Do not apply more than a cumulative total of 1 lb ae/A postemergence over the top
Do not apply more than 2 lb ae/A per year (single growing season)

Aerial application is not allowed for preplant, preemergence, or postemergence use in

dicamba

- tolerant cotton or soybean

Sugarcane

Prior to close

- in stage of sugarcane Engenia®

Herbicide 1 2 Do not apply more than 1 lb ae/A in a single application
Do not apply more than a cumulative total of 2 lb ae/A per growing season

Farmstead Turf (Noncropland) and Sod Farms

Farmstead turf (noncropland) and

sod farms Engenia®

Herbicide 0.5 1 Do not apply more than 1 lb ae/A per growing

season

Do not use on residential sites



### 5 .0 Residential Exposure and Risk Estimates

There are no proposed residential uses at this time for either the dicamba acid or the dicamba

BAPMA salt ; however, there are existing residential uses of dicamba that have been reassessed in this document to reflect updates to HED’s 2012 Residential SOPs 2 

### alon g with policy changes for body weight assumptions. The revision of residential exposures will impact the human health aggregate risk assessment for dicamba

. The proposed new BAPMA salt of dicamba does not impact the residential assessment as there are no proposed uses of dicamba BAPMA that would result in residential exposure; therefore, only the registered uses of dicamba have been

reassessed in this document.

Registered uses of dicamba include solid products and liquid products in concentrates , granu les or ready

- to

- use sprays for use as spot and broadcast treatments on turf.

5 .1 Residential Handler Exposure/Risk Estimates

HED uses the term “handlers” to describe those individuals who are involved in the pesticide application process. HED believes that there are distinct tasks related to applications and that exposures can vary depending on the specifics of each task. Residential handlers are addressed somewhat differently by HED as homeowners are assumed to complete all elements of an application without use of any protective equipment.

2 Available: h ttp://www2.epa.gov/pesticide

- science

- and

- assessing

- pesticide

- risks/standard

- operating

- procedures

- residential

pesticidePage 13 of 36



### The quantitative exposure/risk assessment developed for residential handlers is based on the following lawn/turf application scenarios:

 Mix/Load/Apply Liquid s with Hand

- held Equipment

 Apply Ready

- To

- Use Sprays with Hand

- held Equipment

 Load/Apply Granule s with Hand

- held Equipment

Residential Handler Exposure Data and Assumptions A series of assumptions and exposure factors served as the basis for completing the residential handler risk assessments. Each assumpt ion and factor is detailed below.

Application Rate : The maximum application rate for residential products on turf is 1 lb ae/acre.

Unit Exposures and Area Treated or Amount Handled : Unit exposure values and estimates for area treated or amount handled were taken from HED’s

2012 Residential SOPs 3



### .

Exposure Duration: Residential handler exposure is expected to be short

- term in duration. Intermediate

- term exposures are not likely because of the intermittent nature of applications by homeowners.

Res idential Handler Non

- Cancer Exposure and Risk Estimate Equations The algorithms used to estimate exposure and dose for residential handlers can be found in Appendix A and/or the 2012 Residential SOPs 3



### .

Combining Exposures/Risk Estimate s: There is n o potential hazard via the dermal route f or dicamba. Only inhalation risk estimate s

were quantitatively assessed

.

Summary of Residential Handler Non

- Cancer Exposure and Risk Estimates The residential handler risk estimates are not of concern for dicamba ( Inhalation MOEs > LOC

of 30 ) for all scenarios.

Table 5.1.1. Residential Handler Non

- cancer Exposure and Risk Estimates for Dicamba Acid.

Exposure Scenario Level of

Concern Inhalation Unit

Exposure (mg/lb ai) Maximum

Application

Rate 1 Area Treated or

Amount Handled Daily 2 Inhalation

Dose (mg/kg/day) 5 MOE 6

Mixer/Loader/Applicator

Lawns/Turf, Liquid, Hose

- end Sprayer

30 0.022 1 lb ae/acre 0.5 acres 0.00014 510

Lawns/Turf, Liquid, Sprinkler Can 0.000023 lb

ae/ft 2 1000 ft 2 0.0000063 11,000

Lawns/Turf, Liquid, Manually

pressurized handwand 0.018 0.05 lb ae/gallon 5 gallons 0.000056 1,200

Lawns/Turf, Liquid, Backpack 0.14 0.00044 160

3 Available: http://www2.epa.gov/pesticide

- science

- and

- assessing

- pesticide

- risks/standard

- operating

- procedures

- residential

pesticidePage 14 of 36

Table 5.1.1. Residential Handler Non

- cancer Exposure and Risk Estimates for Dicamba Acid.

Exposure Scenario Level of

Concern Inhalation Unit

Exposure (mg/lb ai) Maximum

Application

Rate 1 Area Treated or

Amount Handled Daily 2 Inhalation

Dose (mg/kg/day) 5 MOE 6

Lawns/Turf, RTU, Hose

- end Sprayer 0.034 1 lb ae/acre 0.5 acres 0.00021 330

Lawns/Turf, Granule, Push

- type rotary

spreader 0.0026 1 lb ae/acre 0.5 acres 0.000016 4,300

Lawns/Turf, Granule, Belly grinder 0.039

0.000023 lb

ae/ft 2 1200 ft 2 0.000013 5,200

Lawns/Turf, Granule, Spoon 0.087

100 ft 2 0.0000025 28,000

Lawns/Turf, Granule, Cup/Shaker Can 0.013 0.00000037 190,000

Lawns/Turf, Granule, Hand Dispersal 0.38 0.000011 6,400
Liquid = Liquid concentrate; RTU = Ready

- to

- use 1 Based on registered uses

. Application rate is 1 lb ae/ acre

. 1 lb ae per acre with an assumed minimum of 2 0 gallons used per

acre = 0.05 lb ae /gal ; 1 lb ae /acre * 1 acre/43560 ft 2 = 0.0000344 lb ae /ft 2

2 Based on HED’s 2012 Residential SOPs ( http://www2.epa.gov/pesticide

- science

- and

- assessing

- pesticide

- risks/standard

operating

- procedures

- residential

- pesticide ).

5 Inhalation Dose = Inhalation Unit Exposure (mg/lb ai) × Application Rate (lb ai/ area or volume ) × A rea Treated or Amount Handled (ar ea

/day or volume /day) ÷ B ody W eight ( 80 kg).

6 Inhalation MOE = Inhalation NOAEL ( 0.084 mg/kg/day) ÷ Inhalation Dose (mg/kg/day).



### 5

. 2 Residential Post

- application Exposure/Risk Estimates

There is the potential for post

- application exposure for individuals exposed as a result of being in an environment that has been previously treated with dicamba

. The quantitative exposure/risk

assessment for residential post

- application exposures is base d on the following scenarios:

 Children (1 to < 2 years old) incidental oral exposure to treated turf

.

 Children ( 1 to < 2 year s old ) episodic granular ingestion exposure

.

Assessment of post

- application exposure to liquid formulations is protective of exposure to solid formulations, except for the episodic granular ingestion scenario which was quantitatively

assessed.

The lifestages selected for each post

- application scenario are based on an analysis provided as an Appendix in the 2012 Residential SO Ps 4 

### . These lifestages are not the only lifestages that could be potentially exposed for these post

- application scenarios; however, the assessment of these lifestages is health protective for the exposures and risk estimates for any other potentially

expos ed lifestages.

Residential Post

- application Exposure Data and Assumptions A series of assumptions and exposure factors served as the basis for completing the residential
post

- application risk assessment . Each assumption and factor is detailed in the 2012 Residential

SOPs and can be found in Appendix A

. In addition to the standard assumptions, chemical

specific turf transferable residue data (TTR) are available for dicamba and have been used in risk assessment. These data are summarized briefly below.

4 Av ailable: : http://www2.epa.gov/pesticide

- science

- and

- assessing

- pesticide

- risks/standard

- operating

- procedures

- residential

pesticidePage 15 of 36



### Turf Transferable Residue Data

There are chemical

- specific turf transferable residue (TTR) data available for dicamba; these

data are described below.

MRID 44655702 (Reviewed in Memo, A. Lamay, D410014, 14

- MAR

- 2013) 

### : This study

measured the transferable turf residue (TTR) of 2,4

- D 2

- EHE, 2,4

- D, MCPA 2

- EHE, MCPA, 2,4

- DP 2

- EHE, 2,4

- DP, MCPP, and dicamba from turf treated with emulsifiable

concentrate /liquid formulation s



### . The trial was conducted at one location ( Franklin County,

North Carolina ), consisting of 10 established turf plots, including one control plot (TRT1) and one plot for each of the test substances (TRT2

– TRT9). Samples were collected from treated plots using the modified California Roller technique at the following time points : before the application ; at 3 and 8

- 12 hrs after the application ; and then at 1, 2, 3, 4, 5, 6, 7, 10, and 14 days after the application . This study was reviewed by HED and found to be acceptable for risk assessment purposes. A summary of the dicamba re si due data and the regression analysis is presented below in Table 5.2.1

. The predicted day 0 residue from the regression analysis is 0.055 μg/cm 2 

### ; this residue is equivalent to 0.275 μg/cm 2 

### when adjusted from the study rate of 0.2 lb ae/acre for the maxi mum application

rate of 1 lb ae/acre.

Table 5.2.1

. Dicamba Summary of TTR Data and Regression Analysis (MRID 44655702)

Statistic TRT9

– Dicamba

Application Rate (lb a e /A) 0.2
Peak TTR ( μg/cm 2 ) 0.051

Time Interval Of Peak TTR 8

- 12 hr after application Measured Average Day 0 Residue (μg/cm 2 ) 0.018 Predicted Day 0 Residue (μg/cm 2 ) 0.055 Slope

- 2.28

Half

- life (days) 0.31

R 2 0.884



### MRID 45033101 (Reviewed in Memo, A. Lamay

, D410012, 14

- MAR

- 2013) 

### : This study was designed to determine the TTR of 2,4

- D, MCPA, MCPP, dicamba, and 2,4

- DP from

turf treated with liquid formulations

. Trials were conducted at two locations in the United States ( Tulare County, California and Dane County, Wisconsin ), with eac h s ite consisting of five established turf plots, including one control plot (TRT1) and one

treated plot for each of the test substances (TRT2

– TRT5). Transferable residues were

collected from the treated plots using the modifie d California Roller techni que at the following time points: before the application ; at 1, 4, 8, and 12 hrs after the application ; and then at 1, 2, 3, 4, and 7 days af ter the application. A regression analysis was not performed due to the nature of the dissipation pattern. Lower residues occurred at the Wisconsin site likely due to rainfall during sampling; no rain occurred at the California site. Data at 12 hr after application at the California test site was taken out of the analysis as there was dew at this time point.Page 16 of 36 Table 5.2.2

. Dicamba Summary of TTR Data and Regression Analysis (MRID 45033101)

Statistic TRT4

– California TRT4

– Wisconsin

Application Rate (lb a e /A) 0.2 1 0.21

Peak TTR ( μg/cm 2 ) * 0.1595 Not including 12 hr time point: 0.022 0.0258

Time Interval Of Peak TTR * 12hr after application Not including 12hr time point: 1 hr after application 8hr after application

*Peak de termined without the residue value at 12 hr after application at the C alifornia site as there was dew at this time point

.



### MRID 44655703 (Reviewed in Memo, A. Lamay

, D410013, 14

- MAR

- 2013) 

### : This study was designed to determine the TTR of 2,4

- D, MCPP, and dicamba from turf treated with

a suspension concentrate/liquid (SC/L) formulation at one location (Franklin County, NC) when applied using various spray volumes. The treated plots were treated with EH

1358 mixed to achieve a target spray volume of 2, 5, and 20 gallons per acre (GPA) for treatments 2,3 and 4 respectively. Transferable residues were collected using the modified California Roller technique before and after application and up to 14 days following application . This study was reviewed by HED and found to be acceptable for risk assessment purposes. A summary of the dicamba residue data and the regressions analysis is presented below in Table 5.2.3. The predicted day 0 residues from the regression analyses are 0.036 μg/cm 2 

### , 0.041 μg/cm 2 

### , and 0.032 μg/cm 2 

### for treatments 2, 3 and 4, respectively; these residues are equivalent to 0. 16 μg /cm 2 

### , 0.18 μg/cm 2 

### , and 0.14 μg/cm 2 

### for treatments 2, 3, and 4, respectively when adjusted from the study rate of 0.22

lb ae/acre for the maximum application rate of 1 lb ae/acre.

Table 5.2.3

. Dicamba Summary of TTR Data and Regression Analysis (MRID 44655703)

Statistic TRT2

– 2 GPA TRT3

- 5 GPA TRT4

- 20 GPA

Application Rate (lb a e /A) 0.222 0.222 0.218
Peak TTR ( μg/cm 2 ) 0.036 0.036 0.028

Time Interval Of Peak TTR 1DAT 0DAT 8

- 12hr after application Measured Average Day 0

Residue (μg/cm 2 ) 0.027 0.036 0.020

Predicted Day 0 Residue (μg/cm 2 ) 0.036 0.041 0.032

Slope

- 1.81

- 2.15

- 2.09

Half

- life (days) 0.38 0.32 0.33

R 2 0.623 0.935 0.943



### MRID 44959001 : This study measured dicamba TTR after a soluble concentrate

formulation in water was applied to turf at a single application rate of 1 lb ae/acre at three test sites in Florida, California, and Pennsylvania . Transferable residues were collected using the modifie d California Roller technique at each location immediately before an d after each application; 4 hours, 8 hours, 24 hours, 36 hours, 48 hours, 60 hours after application as well as 3, 5, and 7 days after treatment (DAT). This study was reviewedPage 17 of 36



### by HED and found to be acceptable for risk assessment purposes. A summary of t he

dicamba residue data and the regression analysis is presented below in Table 5.2.4.

Treatment 2 results from the Pennsylvania site were not included in this summary as the plot was irrigated and the linear regression of the data had an R

- squared value of 0.00594, and thus could not be used to calculate a half

- life

. The predicted day 0 residues from the regression analyses are 0.13 μg/cm 2 

### , 0.15 μg/cm 2 

### , and 0.13 μg/cm 2 

### for the Florida, California, and Pennsylvania locations, respectively

.

Table 5.2.4

. Dicamba Summary of TTR Data and Regression Analysis (MRID 44959001)

Statistic Florida

– No Irrigation California

- No

Irrigation Pennsylvania

TRT1

– No Irrigation Application Rate (lb a e /A) 1 1 1
Peak TTR ( μg/cm 2 ) 0.29 0.135 0.13

Time Interval Of Peak TTR 8 hr after

treatment 0DAT 4 hr after treatment

Predicted Day 0 Residue (μg/cm 2 ) 0.126 0.15 0.128

Slope

- 1.6

- 0.62

- 0.46

Half

- life (days) 0.43 1.1 1.5

R 2 0.58 0.95 0.93



### Conclusion

The highest adjusted predicted day 0 residue for dicamba was from MRID 44655702. The predicted day 0 residue from the regression analysis is 0.055 μg/cm 2 

### ; this residue is equivalent to 0.275 μg/cm 2 

### when adjusted for the maximum application rate of 1 lb

ae/ ac re. However, MRID 44959001 was conducted at the maximum application rate being assessed

, with predicted residues of approximately 0.15 μg/cm 2 

### consistent ly

measured in three different site locations; therefore, HED has determined it is scientifically valid to use the results from this study for risk assessment purposes.

Episodic Granular Ingestion Assumptions: It should be noted that the standard assumption for granule ingestion rate per day for dicamba has been adjusted from the recommended 2012 Residential SOP value due to product

- specific information available. The default ingestion rate for dry pesticide formulations (e.g., pellets and granules) is 0.3 gram/day for children 1 < 2 years

old in the 2012 Residential SOPs . It is assumed that if 150 pounds of product were to be applied to a 1⁄2 acre lawn, the amount of product per square foot would be approximat ely 3 g/ft 2 

### and a

child would consume one

- tenth of the product available in a square foot. T he maximum application rate for dicamba on lawns is 1 lb ae/acre, and the maximum percent of active ingredient in dry formulation is 1 %, therefore, the maximum amo unt of product to treat an acre is 100 pounds; or a maximum of 50 pounds of product to treat a half

- acre. Therefore, the point estimate for granular ingestion rate has been reduced by a third to 0.1 grams/day (see Appendix A)

.

Residential Post

- applicat ion Non

- Cancer Exposure and Risk Equations The algorithms used to estimate residential post

- application exposure and dose can be found in Appendix A and/or the 2012 Residential SOPs.Page 18 of 36



### Combining Exposure and Risk Estimates There is no potential hazard via t he dermal route f or dicamba . Only incidental oral risk estimates

were quantitatively assessed. The incidental oral scenarios (i.e., hand

- to

- mouth and object

- to

mouth) should be considered inter

- related and it is likely that they occur interspersed amongst

each other across time. The g ranular ingestion scenario is not combined as this exposure would not occur as a result of routine behavior and is considered an episodic event related to poisoning. Therefore, no post

- application exposure scenarios were combined for children 1 < 2 years old.

Summary of Residential Post

- application Non

- Cancer Exposu re and Risk Estimates The residential post

- application risk estimates are not of concern for dicamba. MOEs are greater

than the level of concern of 100 for incidental oral scenarios and episodic ingestion

. All

scenarios are short

- term exposures, except e pisodic granular ingestion which is an acute scenario. Incidental soil ingestion scenario is short

- term exposure only as the soil half

- life for dicamba is 18 days (EFED memo, I. Maher, D378447, 11/22/10).

Table 5.2.1. Residential Post

- application Non

- ca ncer Exposure and Risk Estimates for Dicamba.

Lifestage Post

- application Exposure Scenario Application

Rate 1 TTR

(ug/cm 2 ) 2 Dose

(mg/kg/day) MOE

(LOC = 100) 3 Use Site Route of Exposure

1 to < 2 years old Turf

- liquid Hand

- to

- Mouth

1 lb ae/acre 0.15 0.02055 6,600
Object

- to

- Mouth 0.00062 220,000
Soil Ingestion 0.000034 4,000,000

Turf

- Granular Episodic Granular Ingestion 1% ai 0.27 320 A

1 Based on registered uses (reference: 2005 RED).

2 TTR based on MRID 44959001

. 3 MOE = Incidental oral POD (136 mg/kg/day) ÷ Dose (mg/kg/day) for hand

- to

- mouth, object

- to

- mouth, and soil ingestion scenarios.

LOC = 100. A Ingestion of granules is considered episodic in nature; MOE was calculated using the acute dietary POD (29 mg/kg/day) and LOC (100).



### 5

. 3 Residential Risk Estimates for Use in Aggregate Assessment

Table 5.3.1 reflects the residential risk estimates that are recommended for use in the aggregate assessment for dicamba. Inhalation exposures are not included in the aggregate assessment since effects from the inhalation route are not systemic/cannot be aggregated. Post

- application episodic granular ingestion following applications to lawns and turf are not included in the aggregate assessment as this exposure would not occur as a result of routine behavior and is considered an episodic event related to poisoning. T here is no recommended residential exposure for use in the adult aggregate assessment since there is no hazard via the dermal route of exposure and inhalation exposures are not included, as described above. Therefore, the only residential

exposures recomm ended for the dicamba aggregate assessment are the following:

 The recommended residential exposure for use in the children (1 to <2 years old) aggregate assessment reflects hand

- to

- mouth exposures from pos t

- application turf scenario (i.e., post

- application exposure to treated turf).Page 19 of 36

Table 5.3.1 . Recommendations for the Residential Exposures for the Dicamba Aggregate Assessment.

Lifestage Exposure

Scenario Dose (mg/kg/day) 1 MOE 2

Dermal Inhalation Oral Total Dermal Inhalation Oral Total

Child Hand

- to

Mouth

Post

application Exposure

– Treated

Turf N/A N/A 0.02055 0.02055 N/A N/A 6,600 6,600

1 Dose = the highest dose for each applicable lifestage of all residential scenarios assessed . Total = dermal + inhalation + incidental oral

(where applicable)

. 2 MOE = the MOEs associated with the highest residential doses . Total = 1 ÷ (1/Dermal MOE) + (1/Inhalation MOE) + (1/Incidental

Oral MOE), where applicable

.



### 6.0 Non

- Occupational Spray Drift Exposure and R isk Estimates

Off

- target movement of pesticides can occur via many types of pathways and it is governed by a variety of factors. Sprays that are released and do not deposit in the application area end up off

target and can lead to exposures to those it m ay directly contact. They can also deposit on surfaces where contact with residues can eventually lead to indirect exposures ( e.g. , children playing on lawns where residues have deposited next to treated fields). The potential risk

estimates from these res idues can be calculated using drift modeling coupled with methods employed for residential risk assessments for turf products.

The approach to be used for quantitatively incorporating spray drift into risk assessment is based on a premise of compliant app lications which, by definition, should not result in direct exposures to individuals because of existing label language and other regulatory requirements intended to prevent them. 5 

### Direct exposures would include inhalation of the spray plume or being spra yed directly. Rather, the exposures addressed here are thought to occur indirectly through contact with impacted areas, such as residential lawns, when compliant applications are conducted. Given this premise, exposures for children (1 to 2 years old) an d adults who have contact with turf where residues are assumed to have deposited via spray drift thus resulting in an indirect exposure are the focus of this analysis analogous to how exposures to turf products are

considered in risk assessment.

Dicamba : Several dicamba products have existing labels for use on turf, thus it was considered whether the risk assessment for that use may be considered protective of any type of exposure that would be associated with spray drift. It should be noted that t he registered residential uses on turf result in exposure greater than potential exposure from spray drift; therefore, no new

residential assessment needs to be completed. If the maximum application rate on crops adjusted by the amount of drift expected is l ess than or equal to existing turf application rates, the existing turf assessment is considered protective of spray drift exposure. The proposed maximum single application rate of dicamba is 1 lb ae/A

. The highest degree of spray drift noted for any

app lication method immediately adjacent to a treated field (Tier 1 output from the aerial

5 

### This approach is consistent with the requirements of the EPA’s Worker Protection Standard which, when included on all labels, precludes direct exposure pathways.Page 20 of 36



### application using fine to medium spray quality) results in a deposition fraction of 0.26 of the application rate. A quantitative spray drift assessment for dicamba is n ot required because the

max imum application rate to a crop/ta rget site multiplied by the adjustment factor for drift of

0.26 is less than the maximum direct spray residential turf application rate 1 lb ae/A 6 

### for any

dicamba products . The turf post

- applica tion MOEs have been previously assessed and are based on the revised SOPs for Residential Exposure Assessment (i.e., see above in Section 6 .2).

BAPMA salt: In order to evaluate the drift potential and associated risks for the BAPMA salt, an approach base d on drift modeling coupled with techniques used to evaluate residential uses of pesticides was utilized. Essentially, a residential turf assessment based on exposure to deposited residues has been completed to address drift from the agricultural applicati ons of the BAPMA

salt

. In the spray drift scenario, the deposited residue value was determined based on the amount of spray drift that may occur at varying distances from the edge of the treated field using the AgDrift ( v2.1.1) model and the Residential Exposure Assessment Standard Operating Procedures Addenda 1: Consideration of Spray Drift Policy

. Once the deposited residue values were determined, the remainder of the spray drift assessment was based on the algorithms and input values specified in the r ecently revised (2012) Standard Operating Procedures For

Residential Risk Assessment (SOPs)

.

A screening approach was developed based on the use of the AgDrift model in situations where specific label guidance that defines application parameters is not a vailable. 7 

### AgDrift is appropriate for use only when applications are made by aircraft, airblast orchard sprayers, and groundboom sprayers. When AgDrift was developed, a series of screening values (i.e., the Tier 1 option) were incorporated into the model and represent each equipment type and use under varied conditions. The screening options specifically recommended in this methodology were selected because they are plausible and represent a reasonable upper bound level of drift for common application met hods in agriculture. These screening options are consistent with how spray drift is considered in a number of ecological risk assessments and in the process used to develop drinking water concentrations used for risk assessment. In all cases, each scenar io is to be evaluated unless it is not plausible based on the anticipated use pattern (e.g., herbicides are not typically applied to tree canopies) or specific label prohibitions (e.g., aerial applications are not allowed).

The spray drift risk estimate s are based on an estimated deposited residue concentration as a result of the screening level agricultural application scenarios. BAPMA salt is proposed for used on numerous agricultural crops and can be applied via aerial and groundboom equipment. The recommended drift scenario screening level options are listed below:

 Groundboom applications are based on the AgDrift option for high boom height and using very fine to fine spray type using the 90 th 

### percentile results.

 Aerial applications are based on the use of AgDrift Tier 1 aerial option for a fine to medium spray type and a series of other parameters which will be described in more detail below (e.g., wind vector assumed to be 10 mph in a downwind direction for entire application/drift event).

6 1 lb ae/A x 0.26 ≤ 1 lb ae/A

7 http://www.agdrift.com/Page 21 of 36



### Only incidental oral risk estimates were estimated since there is not dermal hazard for the BAPMA salt. The total applicable LOC is 100 so MOEs < 100 would be of concern. Children’s (1<2 year old) incidental oral risk estimates from indirect exposure to dicam ba BAPMA salt related to spray drift result in no risk estimates of concern at the field edge for groundboom and aerial applications (i.e., all MOEs ≥ 35 ,000)

.

Table 6.0.1. Non

- occupational Risk Estimates Resulting from Spray Drift for BAPMA Salt.

Crop/Rate Group Spray Type/ Nozzle Configuration Application Rate (lb ai/A) Estimated TTR t

(ug/cm 2 ) a HtM MOE at

Field Edge

Aerial Fine to Medium 1 0.11115 35,000

Groundboom High Boom Very fine to Fine 48,000

a. TTR = Application Rate × F × (1

- D) t × 4.54E8 μg/lb × 2.47E

- 8 acre/cm 2

.



### 7.0 Non

- Occupational Bystander Post

- Application Inhalation Exposure and Risk Estimates

The potential exposure to bystanders from vapor phase dicamba and BAPMA salt residues emitted from treated fields has been evaluated for the proposed uses of dicamba on dicamba

tolerant corn and soybean, and for the proposed uses of BAPMA on various agricultural crops. Bystander exposure to dicamba and BAPMA emitted from treat ed fields depends on two main factors: 1) the rate at which these chemicals come off a treated field (described as the off

gassing, emission or flux), and 2) how those vapors are dispersed in the air over and around the

treated field. Volatilization can o ccur during the application process or thereafter. It can result from aerosols evaporating during application, while deposited sprays are still drying ( e.g. , possibly via co

- distillation), or after as dried deposited residues volatilize.

This assessment employs approaches EPA has used previously to assess inhalation exposures to fumigant pesticides 8 

### and is also consistent with the recommendations of the December 2009 Federal Insecticide, Fungicide, and Rodenticide Act Scientific Advisory Panel (SAP) 9 

### meeting on the scientific issues associated with field volatilization of conversional (semi

- volatile) pesticides

.

7. 1 Flux Data

A submitted flux study 10 

### was reviewed by the Environmental Fate and Effects Division (EFED), which estimated the flux of dicamba vapors after spray application of the DGA salt formulation. The dicamba DGA salt formulation was used alone without any tank adjuvants, and the test

8 U.S. EPA 2004d. FIFRA Science Adv isory Panel Meeting Minutes

- Fumigant Bystander Exposure Model Review: Probabilistic Exposure and Risk Model for Fumigants (PERFUM) Using Iodomethane as a Case Study. Available at http://www.epa.gov/scipoly/sap/meetings/2004/august1/august2425minutes.pdf

9 U.S. EPA 2009. FIFRA Science Advisory Panel Meeting Minutes

- Scientific Issues Associated with Field Volatilization of Conventional Pesticides. Available at http://www.epa.gov/scipoly/sap/meetings/2009/december/120309meetingminutes.pdf

10 Memo, D 411382

, W. Eckel. MRID 49022501. Sall, E.; Smith, H.; Findley, D.; et al. (2013) Measurement of the Volatile Flux

of Dicamba under Field Conditions using the Theoretical Profile Shape Method. Project Number: RPN/2012/0662, MSL0024798. Unpublished study prepared b y Monsanto Company. 52p.Page 22 of 36



### surface was zoysiagrass. The trial was performed in August 2012 near Co lumbia, IL, and experienced minimum and maximum temperatures of 21.1 o 

### C and 26.2 o 

### C, respectively.

A circle in the zoysiagrass with a diameter of 40 m (~131 ft) was sprayed with a tank mix of 32 oz/A (1.0 lb a.e./A) Clarity ® 

### (EPA Reg. # 7969

- 137) . Herbicid e treatments were applied using a nitrogen pressurized backpack sprayer calibrated to deliver 10 gallons per acre (GPA) at 50 PSI using TeeJet ® 

### TTI 110015 spray tips. Application of the test substance was made approximately perpendicular to the prevailing wind direction. In the test plot, three air samplers and an anemometer were placed in the treatment area after post

- application drift was allowed to settle (typically 2

- 5 minutes). Data were collected for 0

- 6 hours after application.

The field test m ethod employed was the Theoretical Profile Shape (TPS) method which calls for circular spray plots of a certain diameter, with air sampling and wind velocity measurements acquired at the center of the circle at a certain, single height determined by the ci rcle size and the surface roughness. A short description of the TPS method and calculations is provided in an Appendix of the study report.

The estimated 6 hr average flux from the Clarity ® 

### application on zoysiagrass was 0.4 (+/

- 0.1) ng/m 2 

### /sec, representing 0.008% of the application rate. Quantitative analysis using the estimated flux rate derived from this study is described below.

While the flux data are specific to the DGA salt of dicamba, it is considered protective for the

BAPMA salt form of dicamba as well. BAPMA is considered less volatile than the DGA salt and, therefore, would be expected to result in lower air concentrations as a result of flux from a treated field. Based on modeling data using EPISuite and information provided in a BASF
patent 11 

### , the volatility of the BAPMA salt is lower than that of the DGA salt. EPISuite estimated the vapor pressure of the DGA salt as 1.48E

- 11 mmHg at 25 o 

### C, and for BAPMA as 1.10E

- 21 mmHg at 25 o 

### C. The BASF patent provides a relative ranking of the volatility of the various forms of dicamba (compared to the acid at 100%), with the BAPMA salt being 0.5% of the volatility of the dicamba acid and the DGA salt being 5.4% of the dicamba acid. Therefore,

HED believes that the volatilization assessment co nducted using the flux data for the DGA salt is protective of the BAPMA salt.

7 .2 Volatilization Modeling and Risk Assessment

Exposure modeling for a single day was completed using Probabilistic Exposure and Risk model for FUMigants ( PERFUM). There are a variety of factors that potentially affect the emission

rates of dicamba and subsequent offsite transport including: field condition (bare soil, growing or mature crop canopy), field parameters (soil type, moisture, etc.) , formulation type,

m eteorological conditions, and application scenario (rate, method)

. The flux estimate from the study ( 0.0004 ug/m 2 

### /s) , a single 40A field, and the Bradenton, FL meteorological data were used with PERFUM to estimate risk based on the dicamba field volatility study summarized in

Section 7 .1.

11 Low volatile amine salts of anionic pesticides. USPTO Application: #20150210723.

http://images3.freshpatents.com/pdf/US20150210723A1.pdfPage 23 of 36



### The short

- term residential inhalation endpoint s for dicamba and BAPMA were used in the

volatilization assessment (dicamba acid: 530 ug/m 3 

### and LOC of 30; BAPMA salt: 50 ug/m 3 

### ; LOC = 300). This is considered a conservative assumption to compare the day 1 volatilization exposure to a short

- term HEC. Furthermore, a 6

- hour exposure avera ging period was used in the model; it is a conservative assumption to compare the 6 hour average exposure from the model to the HEC calculated for 24 hours of exposure especially sin c e the 6 hour exposure period used as the basis for the comparison represe nts the peak emissions period after application.

All of the files associated with the use of PERFUM in this assessment can be provided upon request. These files could be used to examine the detailed input and output files for each permutation of the mo del completed for this analysis.

7 .3 Volatilization Risk Estimates

The field volatility study suggest s that volatilization of dicamba and BAPMA from treated crops

does occur and could result in bystander exposure . Results of PERFUM modeling, however, indicate that airborne concentrations, even at the edge of the treated fields, are not of concern. The maximum proposed application rate of 1 lb a.e ./A was assessed. There were no whole field and maximum field buffers estimated using PERFUM (i.e., risks were acceptable at all percentiles of exposure at the edge of a treated field).

8.0 Occupational Exposure and Risk Estimates

8.1 Occupational Handler Exposure/Risk Estimates

HED uses the term handlers to describe those individuals who are involved in the pesticide application process. HED believes that there are distinct job functions or tasks related to applications and exposures can vary depending o n the specifics of each task. Job requirements (amount of chemical used in each application), the kinds of equipment used, the target being treated, and the level of protection used by a handler can cause exposure levels to differ in a manner specific to each application event.

Based on the anticipated use patterns and current labeling, types of equipment and techniques that can potentially be used, occupational handler exposure is expected from the proposed uses. The quantitative exposure/risk assessm ent developed for occupational handlers for the dicamba

DGA salt uses is based on the following scenarios:

 Mixing/loading liquid in support of groundboom application to high

- acreage crops (cotton and soybean)

 Applying spray by groundboom equipment to hig h acreage crops (cotton and soybean)

The quantitative exposure/risk assessment developed for occupational handlers for the dicamba

BAPMA salt uses is based on the following scenarios:

 Mixing/loading liquid in support of aerial application to sod, typica l field crops (asparagus), and high

- acreage crops (corn, soybean, cotton, sugarcane)Page 24 of 36



###  Mixing/loading liquid in support of groundboom application to sod, typical field crops (asparagus), and high

- acreage crops (corn, soybean, cotton, sugarcane)

 Applying spra y by aerial equipment to sod, typical field crops, and high

- acreage crops

 Applying spray by groundboom equipment to sod, typical field crops, and high

- acreage

crops

 Flagging in support of aerial application to sod, typical field crops, and high

- acreage

cro ps

Occupational Handler Exposure Data and Assumptions

A series of assumptions and exposure factors served as the basis for completing the occupational handler risk assessments. Each assumption and factor is detailed below on an individual basis.

Applic ation Rate : The maximum single application rate for tolerant soybean and cotton is 1 lb ae/acre . S ee Table 4.1 for a summary of use directions

.

Unit Exposures : It is the policy of HED to use the best available data to assess handler exposure.

Sources of generic handler data, used as surrogate data in the absence of chemical

- specific data, include PHED 1.1, the AHETF database, the Outdoor Residential Exposure Task Force (ORETF) database, or other registrant

- submitted occupational exposure studies. Som e of these data are proprietary (e.g., AHETF data), and subject to the data protection provisions of FIFRA. The standard values recommended for use in predicting handler exposure that are used in this assessment, known as “unit exposures”, are outlined in the “Occupational Pesticide Handler Unit Exposure Surrogate Reference Table 12 

### ”, which, along with additional information on HED policy on use of surrogate data, including descriptions of the various sources, can be found at the Agency website 13



### .

Area Trea ted or Amount Handled : Based on ExpoSAC Policy 9.1 :

 T he area treated for groundboom application to sod and typical field crops is 80 acres per day and to high acreage crops is 200 acres per day.

 The area treated for aerial application to sod and typical field crops is 350 acres per day and to high acreage crops is 1200 acres per day.

Exposure Duration: HED classifies exposures from 1 to 30 days as short

- term and exposures 30 days to six months

as intermediate

- term. Exposure duration is determined by many things, including the exposed population, the use site, the pest pressure triggering the use of the pesticide, and the cultural practices surrounding that use site. For most agricultural uses, it is reasonable to believe that occupational handlers will not apply the same chemical every day for more than a one

- month time frame; however, there may be a la rge agribusiness and/or commercial applicators who may apply a product over a period of weeks (e.g., completing multiple applications for multiple clients within a region).

12 Available: http://www2.epa.gov/sites/production/files/2015

- 09/documents/handler

- exposure

- table

- 2015.pdf

13 Available: http://www2.epa.gov/pesticide

- science

- and

- assessing

- pesticide

- risks/occupational

- pesticide

- handler

- exposure

- dataPage 25 of 36



### For dicamba , based on the proposed use, short

- and intermediate

- term exposures a re expected as the product can have multiple applications to the crop throughout the season and applicators may apply the product to multiple farms throughout the growing season.

Mitigation/Personal Protective Equipment : Estimates of inhalation exposure were calculated for various levels of personal protective equipment (PPE) or engineering controls . Results are presented for “baseline,” defined as no respirator, as well as with various levels of respiratory protection . The dicamba product labels curre ntly do not require respiratory protection

.

Occupational Handler Non

- Cancer Exposure and Risk Estimate Equations The algorithms used to estimate non

- cancer exposure and dose for occupational handlers can be found in Appendix A

.

Combining Exposures/ Risk E stimates : There is n o potential hazard via the dermal route f or dicamba. Only inhalation risk estimate s

were quantitatively assessed

.

Summary of Occupational Handler Non

- Cancer Exposure and Risk Estimates

DGA salt of dicamba : The occupational handler risk estimates are not of concern for dicamba acid (inhalation MOEs > LOC of 30) for all scenarios with label required PPE (i.e., no respiratory protection). See Table 8.1.1 below.

Table 8 .1.1. Occupational Handler Non

- Cancer Exposure and Risk Estimates for Dicamba acid (DGA salt)

.

Exposure Scenario Crop or Target Inhalation Unit Exposure ( μ g/lb ai) 1 Maximum

Application

Rate 2 Area

Treated or

Amount

Handled Daily 3 Inhalation

(LOC = 30)

Baseline Mitigation Level ( No Respiratory Protection Unless Otherwise Specified) Dose (mg/kg/day) 4 MOE 5

Mixer/Loader

Mixing/Loading Liquid in Support of Groundboom Application High Acreage Crops 0.219 1 lb ae/acre 200 acres 0.000548 380

Applicator

Applying Spray by Groundboom

Application High Acreage Crops 0.34 1 lb ae/acre 200 acres 0.00085 250

1 Based on the “Occupational Pesticide Handler Unit Exposure Surrogate Reference Table” ( September 201 5 ).

2 Based on proposed label ( Reg. No. 524

- 582 ).

3 Exposure Science Advisory Council Policy #9.1.

4 Inhalation Dose = Inhalation Unit Exposure ( μ g/lb ai) × Conversion Factor (0.001 mg/ μ g) × Application Rate (lb ai/acre or gal) × Area Treated or Amount Handled (A or gal/day) ÷ BW (kg).

5 Inhalation MOE = Inhalation POD ( 0.21 mg/kg/d ay) ÷ Inhalation Dose (mg/kg/day).



### BAPMA salt of dicamba : Most occupational handler risk estimates are of concern for dicamba BAPMA salt (inhalation MOEs < LOC of 300) based on label

- required PPE (i.e., no respiratory protection). See Table 8.1.2 for a summary of handler risk estimates below. A summary of handler risk estimates with additional inhalation PPE/ engineering controls to mitigate risks is provided in Table 8.1.3; some handler risk estimates are still of concern with the maximum PPE/Page 26 of 36



### engineer ing controls. Note that HED has no data to assess exposures to pilots using open cockpits. The only data available is for exposure to pilots in enclosed cockpits (i.e., engineering controls). Therefore, in both tables, aerial applicator risk estimates a re shown representing the use of engineering controls.

Table 8 .1.2. Occupational Handler Non

- Cancer Exposure and Risk Estimates for Dicamba BAPMA (Label Required PPE = No Respirator)

.

Exposure Scenario Crop or Target Inhalation Unit Exposure (μg/lb ai) 1 Maximum

Application

Rate 2 Area Treated

or Amount

Handled Daily 3 Inhalation

Baseline Mitigation Level (No Respiratory Protection

Unless Otherwise Specified) Dose (mg/kg/day) 4 MOE

(LOC = 300) 5

Mixer/Loader

Mixing/Loading Liquid in Support of Aerial Application Sod

0.219 0.5 lb ae/A 350 acres 0.000479 42

Typical Field Crops

1 lb ae/A 350 acres 0.000959 21

High Acreage Field Crops 1200 acres 0.00329 6.1

Mixing/Loading Liquid in Support of Ground boom Application Sod 0.5 lb ae/A 80 acres 0.00011 180

Typical Field Crops 1 lb ae/A 80 acres 0.000219 91

High Acreage Crops 200 acres 0.000548 36

Applicator

Applying Spray via Aerial Application Sod

Engineering Control:

0.0049 0.5 lb ae/A 350 acres 0.0000107 1,900

Typical Field Crops

1 lb ae/A 350 acres 0.0000215 930

High Acreage Field Crops 1200 acres 0.0000735 270

Applying Spray by Ground boom Application Sod

0.34 0.5 lb ae/A 80 acres 0.00017 120

Typical Field Crops 1 lb ae/A 80 acres 0.00034 59

High Acreage Crops 200 acres 0.00085 24

Flagger

Flagging in support of Aerial Application Sod

0.35 0.5 lb ae/A

350 acres 0.000766 26

Typical Field Crops

1 lb ae/A 0.00154 13

High Acreage Field Crops 0.00154 13

1 Based on the “Occupational Pesticide Handler Unit Exposure Surrogate Reference Table” ( March 2016 ).

2 Based on proposed label (7969

- GUL)

. 3 Exposure Science Advisory Council Policy #9.1.

4 Inhalation Dose = Inhalation Unit Exposure ( μ g/lb ai) × Conversion Factor (0.001 mg/ μ g) × Application Rate (lb ai/acr e or gal) × Area Treated or Amount Handled (A or gal/day) ÷ BW (kg).

5 Inhalation MOE = Inhalation POD ( 0.02 mg/kg/day) ÷ Inhalation Dose (mg/kg/day).Page 27 of 36

Table 8 .1.3. Occupational Handler Non

- Cancer Exposure and Risk Estimates for Dicamba BAPMA (with additional respiratory protection)

.

Exposure Scenario Crop or Target Inhalation Unit Exposure (μg/lb ai) 1 Maximum

Application

Rate 2 Area

Treated or

Amount

Handled Daily 3 Inhalation MOE

(LOC = 300) 4

Mitigation Level PF5 PF10 Eng. Control

Mixer/Loader

Mixing/Loading Liquid in Support of Aerial Application Sod

PF5: 0.0438

PF10: 0.0219

EC: 0.083 0.5 lb ae/A 350 acres 210 420 110

Typical Field Crops 1 lb ai/A 350 acres 100 210 55

High Acreage Field Crops 1200 acres 30 61 16

Mixing/Loading Liquid in Support of Ground boom Application Sod 0.5 lb ae/A 80 acres 910 1.800 480

Typical Field Crops 1 lb ae/A 80 acres 460 910 240

High Acreage Crops 200 acres 180 360 96

Applicator

Applying Spray via Aerial Application Sod

EC: 0.0049 0.5 lb ae/A 350 acres NA NA 1,900

Typical Field Crops 1 lb ae/A 350 acres NA NA 930

High Acreage Field Crops 1200 acres NA NA 270

Applying Spray by Ground boom Application Sod PF5: 0.068

PF10: 0.034

EC: 0.043 0.5 lb ae/A 80 acres 590 1,200 930

Typical Field Crops 1 lb ae/A 80 acres 290 590 470

High Acreage Crops 200 acres 120 240 190

Flagger

Flagging in support of Aerial Application Sod PF5: 0.07

PF10: 0.035 0.5 lb ae/A

350 acres 130 260 NA

Typical Field Crops 1 lb ae/A 65 130 NA

High Acreage Field Crops 65 130 NA

1 Based on the “Occupational Pesticide Handler Unit Exposure Surrogate Reference Table” ( March 2016 )

2 Based on proposed label (7969

- GUL)

. 3 Exposure Science Advisory Council Policy #9.1.

4 Inhalation MOE = Inhalation POD ( 0.02 mg/kg/day) ÷ Inhalation Dose (mg/kg/day).



### 8

. 2 Occupational Post

- application Exposure/ Risk Estimates

HED uses the term post

- application to describe exposures that occur when individuals are present in an environment that has been previously treated with a pesticide (also referred to as re

entry exposure). Such exposures may occur when workers enter previously treated areas to perform job functions, including activities related to crop production, such as scouting for pests or harvesting. Post

- application exposure levels vary over time and depend o n such things as the type of activity, the nature of the crop or target that was treated, the type of pesticide application, and the chemical’s degradation properties. In a ddition, the timing of pesticide applications, relative to harvest activities, can greatly reduce the potential for post

- application exposure.

8

. 2 .1 Occupational Post

- application Inhalation Exposure/Risk Estimates

There are multiple potential sources of post

- application inhalation exposure to individuals performing post

- application activities in previously treated fields. These potential sources include volatilization of pesticides and resuspension of dusts and/or p articulates that contain pesticides. The agency sought expert advice and input on issues related to volatilization of pesticides from its Federal Insecticide, Fungicide, and Rodenticide Act Scientific Advisory PanelPage 28 of 36



### (SAP) in December 2009, and received th e SAP’s final report on March 2, 2010 ( http://www.epa.gov/scipoly/SAP/meetings/2009/120109meeting.html ). The agency has evaluated the SAP report and has developed a Volatilization Screening Tool and a subsequent Volatilization Screening Analysis ( http://www.regulations.gov/#!docketDetail;D=EPA

- HQ

OPP

- 2014

- 0219 ). During Registration Review, the agency will utilize this analysis to determine if data (i.e., flux studies, ro ute

- specific inhalation toxicological studies) or further analysis is required for dicamba

.

In addition, the Agency is continuing to evaluate the available post

- application inhalation exposure data generated by the Agricultural Reentry Task Force. Given these two efforts, the Agency will continue to identify the need for and, subsequently, the way to incorporate occupational post

- application inhalation exposure into the agency's risk assessments.

8

. 2 .2 Occupational Post

- application Dermal Exposure/Risk Estimates

Occupational Post

- application Dermal Exposure There is no potential hazard via the dermal route for dicamba ; therefore, a quantitative occupational post

- application dermal risk assessment was not completed.

Restricted Entry Interval

The REI specified on the proposed label is based on the acute toxicity of dicamba

. Dicamba is classified as Toxicity Category III via the dermal route, Toxicity Category II for skin irritation potential , and Toxicity Category II for eye irritation

. It is not a skin sensitizer. As there is no hazard via the dermal route of exposure, there are no p ost

- application risks of c oncern on day 0 (12 hours following application). Under 40 CFR 156.208 (c) (2) (iii), ai’s classified as Acute II for acute dermal, eye irritation or primary skin irritation are assigned a 24

- hour REI. Therefore, the [156 subpart K] Worker Protection Statement interim REI of 24 hours is adequate to protect agricultural workers from post

- application exposures to dica mba

.Page 29 of 36



### Appendix A. Summary of Occupational and Residential Non

- cancer Algorithms

Residential Non

- cancer Handler Algorithms

Daily dermal and inhalation exposure (mg/day) for residential pesticide handlers, for a given

formulation

- application method combination, is estimated by multiplying the formulation

application method

- specific unit exposure by an estimate of the amount of active ingredient handled in a day, using the equation below:

E = UE * AR * A

where:

E = exposure (mg/day); UE = unit expo sure (mg/lb ai); AR = application rate (e.g., lb ai/ft 2 

### , lb ai/gal); and A = area treated or amount handled (e.g., ft 2 

### /day, gal/day).

Dermal and/or inhalation absorbed doses normalized to body weight are calculated as:

D = E *AF / BW

where:

D = dose (mg/kg

- day); E = exposure (mg/day); AF = absorption factor (dermal and/or inhalation); and BW = body weight (kg).

Residential Non

- cancer Post

- application Algorithms

Post

- application Dermal Exposure Algorithm

– Physical Activities on Turf Exposure resulting from contacting previously treated turf while performing physical activities is calculated as shown below. Residential post

- application exposure assessment must include calculation of exposure on the day of application. Therefore, though an ass essment can present exposures for any day “t” following the application, it must include “day 0” exposure.

E = TTRt * CF1 * TC * ET

where:

E = exposure (mg/day); TTRt = turf transferable residue on day t (μg/cm 2 

### ); CF1 = weight unit conversion factor (0. 001 mg/μg); TC = transfer coefficient (cm 2 

### /hr); andPage 30 of 36



### ET = exposure time (hr/day).

If chemical

- specific TTR data are available, then surface residues from the day of application should be used (assume that individuals could be exposed to residues immediatel y after application). However, if data are not available, then TTR t 

### can be calculated using the following

formula:

TTR t 

### = AR * F * (1

- FD) t 

### * CF2 * CF3

where:

TTRt = turf transferable residue on day t (μg/cm 2 

### ); AR = application rate (lbs ai/ft 2 

### or lb ai/acre); F = fraction of ai as transferable residue following application (unitless); FD = fraction of residue that dissipates daily (unitless);
t = post

- application day on which exposure is being assessed; CF2 = weight unit conversion factor (4.54 x 10 8 

### μg/lb); and CF3 = area unit conversion factor (1.08 x 10

- 3 

### ft 2 

### / cm 2 

### or 2.47 x 10

- 8 

### acre/cm 2 

### ).

Dermal absorbed doses are calculated as:

where:

D = dose (mg/kg

- day);

E = exposure (mg/day);

AF = absorption factor (dermal); and

BW = body weight (kg).

Table A

- 1 : Turf (Physical Activities)

-- Inputs for Residential Post

- application Dermal Exposure (used to calculate HTM exposure)

Algorithm Notation Exposure Factor (units) Point Estimate(s)

AR Application rate (mass active ingredient per unit area) 1 lb ae/acre

F Fraction of AR as TTR

following application (if

chemical

- specific data is unavailable) L/WP/WDG 0.01

Granules 0.002

F D Daily residue dissipation

(if chemical

- specific data is unavailable) (fraction) L/WP/WDG 0.1

Granules 0.1

TC Transfer

Coefficient (cm 2 /hr) L/WP/WDG Adults 180,000
Children 1 < 2 years old 49,000

Granules Adults 200,000

Children 1 < 2 years old 54,000Page 31 of 36

Table A

- 1 : Turf (Physical Activities)

-- Inputs for Residential Post

- application Dermal Exposure (used to calculate HTM exposure)

Algorithm Notation Exposure Factor (units) Point Estimate(s)

ET Exposure Time

(hours per day) Adults 1.5 Children 1 < 2 years old 1.5

BW Body Weight (kg) Adults 80

Children 1 < 2 years old 11 L/WP/WDG = Liquids/Wettable Powders/Water

- dispersible Granules



### Post

- application Hand

- to

- Mouth Exposure Algorithm

– Physical Activities on Turf Exposure from hand

- to

- mouth activity is calculated as follows (based on the algorithm utilized in

the SHEDS

- Multimedia model ):

E = [HR * ( F

M 

### * SA H 

### ) * (ET * N_Replen) * (1

- (1

- SE ) (Freq_HtM/N

- Replen) 

### )]

where:

E = exposure (mg/day);

HR = hand residue loading (mg/cm 2 

### ); FM = fraction hand surface area mouthed / event (fraction/event); SAH = typical surface area of one hand (cm 2 

### ); ET = exposure time (hr/day); N_Replen = number of replenishment intervals per hour (intervals/hour);

SE = saliva extraction fa ctor (i.e., mouthing removal efficiency); and Freq_HtM = number of hand

- to

- mouth contacts events per hour (events/hour).

and

where:

HR = hand residue loading (mg/cm 2 

### );

Fai hands 

### = fraction ai on hands compared to total surface residue from dermal transfer coefficient study (unitless); DE = dermal exposure (mg); and

SA H 

### = typical surface area of one hand (cm 2 

### ).

Dose, normalized to body weight, is calculated as:

where:

D = dose (mg/kg

- day);Page 32 of 36



### E = exposure (mg/day); and

BW = body weight (kg).

Table A

- 2 : Turf (Physical Activities)

– Inputs for Residential Post

- application Hand

- to

- Mouth Exposure Algorithm

Notation Exposure Factor (units) Point Estimate(s)

Fai hands Fraction of ai on hands

from dermal transfer coefficient study (unitless) Liquid formulations 0.06

Granular formulations 0.027

DE Dermal exposure (mg) Calculated

SA H Typical surface area of one hand (cm 2 ), children 1 < 2 years old 150

AR Application rate

(mass active ingredient per unit area) 1 lb ae/acre

HR Residue available on the hands (mg/cm 2 ) Calculated via (DE * Fai hands )/SA H

F M Fraction hand surface area mouthed (fraction/event) 0.127

N_Replen Replenishment intervals per hour (intervals/hr) 4

ET Exposure time (hrs/day) 1.5

SE Saliva extraction factor (unitless) 0.48

Freq_HtM Hand

- to

- mouth events per hour (events/hr) 13.9

BW Body Weight

(kg) Children 1 < 2 years

old 11



### Post

- application Object

- to

- Mouth Exposure Algorithm

– Physical Activities on Turf Exposure from object

- to

- mouth activity is calculated as follows (based on the algorithm utilized

in SHEDS

- Multimedia):

E = [OR* CF1 * SAM O 

### * (ET * N_Replen) * (1

- (1

- SE O 

### ) (Freq_OtM/N_Replen) 

### )]

where:

E = exposure (mg/day); OR = chemical residue loading on the object on day “t” (ug/cm 2 

### ); CF1 = weight unit conversion factor (0.001 mg/μg);

SAM O 

### = area of the object surface that is mouthed (cm 2 

### /event); ET = exposure time (hr/day); N_Replen = number of replenishment intervals pe r hour (intervals/hour);

SE O 

### = saliva extraction factor (i.e., mouthing removal efficiency); and Freq_OtM = number of object

- to

- mouth contact events per hour (events/hour).

andPage 33 of 36 

### OR = AR * F O 

### * CF2 * CF3

where:

OR = chemical residue loading on the object (μg/cm 2 

### ); AR = application rate (lbs ai/ft 2 

### or lb ai/acre);

F O 

### = fraction of residue available on the object (unitless); CF2 = weight unit conversion factor (4.54 x 10 8 

### μg/lb); and CF3 = area unit conversion factor (1.08 x 10

- 3 

### ft 2 

### /cm 2 

### or 2.47 x 10

- 8 

### acre/cm 2 

### ).

Dose, normalized to body weight, is calculated as:

where:

D = dose (mg/kg

- day);

E = exposure (mg/day); and

BW = body weight (kg).

Table A

- 3 : Turf (Physical Activities)

– Inputs for Residential Post

- application Object

- to

- Mouth Exposure Algorithm

Notation Exposure Factor (units) Point Estimate(s)

AR Application rate (to turf)

(mass active ingredient per unit area) 1 lb ae/acre

F O Fraction of AR as OR following application 1 0.01

SAM O Surface area of object mouthed (cm 2 /event) 10

N_Replen Replenishment intervals per hour (intervals/hour) 4

SE O Saliva extraction factor (fraction) 0.48

ET Exposure time (hours per day) 1.5

Freq_OtM Object

- to

- mouth events per hour (events/hr) 8.8

BW Body Weight (kg) Children 1 < 2 years old 11

1 This SOP assumes that all of the residue on the turf could be transferred to the object (e.g., object residue is equal to turf transferable residue).



### Post

- application Incidental Soil Ingestion Exposure Algorithm

– Physical Activities on Turf Exposure from incidental soil ingestion is calculated as follows:

E = SRt * SIgR * CF1

where: E = exposure (mg/day); SRt = soil residue on day "t" (μg/g);Page 34 of 36



### SIgR = ingestion rate of soil (mg/day); and CF1 = weight unit conversion factor (1 x 10

- 6 

### g/μg).

and

SRt = AR * FS * (1

- F D 

### ) t 

### * CF2 * CF3 * CF4

where:

SR t 

### = soil residue on day "t" (μg/g); AR = application rate (lbs ai/ft 2 

### or lb ai/acre); FS = fraction of ai available in uppermost cm of soil (fraction/cm);

F D 

### = fraction of residue that dissipates daily (unitless); T = post

- application day on which exposure is being assessed; CF2 = weight unit conversion factor (4.54 x 10 8 

### μg/lb); CF3 = area unit conversion factor (1.08 x 10

- 3 

### ft 2 

### /cm 2 

### or 2.47 x 10

- 8 

### acre/cm 2 

### ); and CF4 = soil volume to weight unit conversion factor (0.67 cm 3 

### /g soil).

Dose, normalized to body weight, are calculated as:

where : D = dose (mg/kg

- day);

E = exposure (mg/day); and

BW = body weight (kg).

Table A

- 4 : Turf (Physical Activities)

– Inputs for Residential Post

- application Incidental Soil Ingestion Exposure Algorithm

Notation Exposure Factor (units) Point Estimate(s)

AR Application rate

(mass active ingredient per unit area) 1 lb ae/acre

FS Fraction of AR available in uppermost 1 cm of soil (unitless) 1

F D Daily residue dissipation (fraction) 0.1

SIgR Soil ingestion rate (mg/day) 50

BW Body weight (kg) Children 1 < 2 years old 11



### Post

- application Episodic Granular Ingestion Exposure Algorithm

– Physical Activities on Turf Exposure from incidental ingestion of pesticide pellets or granules is calculated as follows:

E = GIgR* FD * CF1

where:Page 35 of 36



### E = exposure (mg/day); GIgR = ingestion rate of dry pesticide formulation (g /day); FD = fraction of ai in dry formulation (unitless); and CF1 = weight unit conversion factor (1,000 mg/g).

Dose, normalized to body weight, are calculated as:

where : D = dose (mg/kg

- day);

E = exposure (mg/day); and

BW = body weight (kg).

Table A

- 5 : Turf (Physical Activities)

– Inputs for Residential Post

- application Episodic Granular Ingestion Exposure
Algorithm

Notation Exposure Factor (units) Point Estimate(s)

F D Fraction of active ingredient in dry formulation 1%

AR Application rate (lbs/A or lbs/1,000 ft 2 ) 1 lb ae/acre

GIgR Granule ingestion rate per day (g/day) 1 0. 1 *

BW Body Weight (kg) Children 1 < 2 years old 11

1 See discussion below on how this value may be adjusted if product specific information is available.



### Post

- application granular pesticide exposure following applications to lawns and turf would not

occur as a result of routine behavior and is considered an episodic event related to poisoning.

* The default ingestion rate for dry pesticide formulations (e.g., pellets and granules) is 0.3 gram/day for children 1 < 2 years old . It is assumed that if 150 pounds of product were to be applied to a 1⁄2 acre lawn, the amount of product per square foot would be approximately 3 g/ft 2



### and a child would consume one

- tenth of the product available in a square foot. According to the 2012 Residential SOP, if product

- specific information is available, the granular ingestio n rate may be adjusted to reflect the amount of product applied on a per area basis if it is less or more than 150 pounds to a 1⁄2 acre lawn. For instance, if 50 pounds of product is meant to treat a 1⁄2 acre lawn, then the ingestion rate should be reduced by a third to 0.1 grams/day. As the maximum application rate for dicamba on lawns is 1 lb ae/acre, and the maximum percent of active ingredient in dry formulation is 1 %, the maximum amount of product to treat an acre is 100 pounds; or a maximum of 50 pounds of product to treat a half

- acre. Therefore, the point estimate for granular ingestion rate (GIgR) has been reduced by a third to 0.1 grams/day.

Occupational Non

- cancer Handler Algorithms

Potential daily exposures for occupational handlers are calculated using the following formulas:

E=UE * AR * A * 0.001 mg/ugPage 36 of 36



### where:

E = e xposure (mg ai/day),

UE = u nit e xposure (μ g ai/ lb ai),

AR = m aximum application rate according to proposed label (lb ai A or lb ai/gal ), and

A = a rea treated or amount handled (e.g., A/day, gal/day)

.

The daily doses are calculated using the following formula:

ADD= E * AF

BW

where:

ADD = average daily dose a bsorbed in a given scenario (mg ai/ kg / day),

E = e xposure (mg ai/day),

AF = absorption fa ctor (dermal and/or inhalation), and

BW = body weight (kg)

.

Margin of Exposure: Non

- cancer risk estimates for each application handler scenario are calculated using a Margin of Exposure (MOE), which is a ratio of the toxicological endpoint to the daily dose of concern. T he daily dermal and inhalation dose received by occupational

handlers a re compared to the appropriate POD ( i.e.

, NOAEL) to assess the risk to occupational handlers for each exposure route. All MOE values a re calculated using the following formula:

MOE= POD

ADD

where:

MOE = m argin of e xposure: value used by HED to represent risk estimates (unitless),

POD = p oint of d eparture (mg/kg/day)

, and

ADD = average daily dose absorbed in a given scenario (mg ai/kg/day)

.