### Page 2 of 19 Table of Contents

1.0 Executive Summary

................................ ................................ ................................ ............ 3

2.0 Hazard Characterization

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

3.0 Use Patterns

................................ ................................ ................................ ........................ 7

4.0 Occupational Exposure/Risk

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

4. 1 Occupational Handler

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

4.1.1 Data and Assumptions for Handler Exposure Scenarios

............................... 9

4.1.2 Occupational Handler and Exposure Risk Summary

................................ ... 11

4.2 Post

- application Exposure

................................ ................................ ....................... 16

4.2.1 Data and Assumptions for Post

- application Exposure Scenarios

................ 16

4.2.2 Post

- application Exposure and Risk

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

5.0 Residential (Non

- Occupational) Exposure and Risk

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

### Page 3 of 19

1.0 Executive Summary

Lactofen is a n herbicide use d by occupational handler s in agricultural settings. It is typically used early in the growing season, before or shortly after the crop has emerged. This memorandum presents the results of HED’s review of the potential human health risks from

o ccupational exposure to lactofen from its use on soybeans, snap beans, conifer seedlings and strawberries (non

- bearing).

Use Profile

The end

- use products evaluated in this assessment includ e three emulsifiable concentrate (EC) products ( EPA Reg. No. 59639

- 34 , 59639

- 92, and 59639

- 118) and one wettable powder in

water

- soluble packaging (WP in WSP) product (EPA Reg. No. 59639

- 113). Additi onally, four SLN labels, under the main label for EPA Reg. No. 59639

- 34

, were evaluated.

Lactofen may be applied to soybean s as pre

- plant, pre

- emergent , or post

- emergent application, up to the R6 (full seed) growth stage. The maximum single application rate is 0.2 lb ai/A for foliar applications and 0.3 lb ai/A for soil

- directed applications. The pre

- harvest interval (PHI) is 45 to 60 days. For snap beans, a single pre

- emergent application is made to the soil, no later than 48 hours after planting, at a maximum rate of 0.25 lb ai/A

. The PHI is 55 days. For strawberries (non

- bearing), a single pre

- emergent application i s made at a maximum application rate of 0.38 lb ai/A to the soil before transplanting or to dormant strawberry plants within 48 hours of transplanting; the plants should have soil placed over the crown of th e plant before the application. The PHI is 1 year. For conifers, lactofen may be applied to the soil or seedlings in outdoor settings including plantations and nurseries (not forest s ) at a maximum single application rate of 0.25 lb ai/A. Handlers may apply lactofen to soybeans, snap beans, conifer seedlings and strawberries (non

- bearing) using aerial and groundboom equipment. Applications to conifers may also be applied using handg un equipment.

Based on application rates and label information, exposure is expected to occur for short

- (1 to 30 days) and intermediate

- term (1 to 6 months) durations

. Long

- term (6 months or greater) occupational exposure is not expected with these use patterns.

Hazard Characterization

Lactofen has a low acute toxicity profile based on its classification in Toxicity Category II I via the dermal route and Toxicity Category IV via t he oral and inhalation routes. It is not a skin

sensitizer

, but it is a very slight dermal irritant. The manufacturing use product is classified as a moderate eye irritant.

The point of departure (PoD) selected for regulation of dermal and inhalation risk at short

- and

intermediate

- term durations is the lowest observed adverse effect level (L OAEL) of 5 mg/kg/day, based on decreases in live young per litter a ccompanied by increases in post

implantation lo ss and in early embryonic death per litter. A no observed adverse effect level (NOAEL) was not established for this st udy. Since the dermal PoD was selected from an oral study

, a 20% der mal absorption factor was used to estimate dermal dose

. Inhalation doses were

### Page 4 of 19

converted to oral equivalent doses, assuming an absorption factor of 100%

. T he average body weig ht of an ad ult (8 0 kilograms) was used in the exposure assessment s. Since the dermal and inhalation PoDs were the same, margins of exposure (MOEs) were combined to provide a total margin of exposure for handler exposure scenarios.

Lactofen is classified as “Not likely to be carcinogenic to humans.”

HED’s level of concern (LOC) for lactofen short

- and intermediate

- term dermal and inhalation exposures is 300 (i.e., an MOE ≥ 300 is not of concern to HED). The LOC is based on a 10X to account for interspecies extrapolation (differences between humans and animals), a 10X to account for intraspecies sensitivity (differences among humans), and an additional 3X factor to

account for the extrapolation of a LOAEL to N OAEL.

Occupational Handlers

HED has determined that there is potential for short

- and intermediate

- term dermal and

inhalation occupational exposure to lactofen during handling activities (e.g., mixing, loading and application). None of the occupational handler exposure scenarios assessed result in combined dermal and inhalation risks of concern (i.e., an MOE ≥ 300) at either baseline attire, with the

addition of chemical

- resistant gloves

, and/ or engineering control s

.

Occupational Post

- application

HED has determined that there is potential for occupational post

- application dermal exposure to lactofen following use on soybeans and conifer seedlings. Post

- application exposures for soybean are not assessed in this action, however, because the exposure is anticipated to be

simi lar to that previously assessed previously for peanut. Post

- application exposures are considered to be negligible for the use of lactofen on snap beans and strawberry (non

- bearing) based on label application instructions (i.e., soil

- directed applications) ; therefore, post

application exposures and risks to occupational workers for the snap bean and strawberry uses were not quantitatively assessed.

Based on a post

- application assessment of common agricultural practices an ticipated for conifer seedlings

, risks were not of concern (i.e., MOEs ≥ 300) on Day 0 (12 h ou rs after application ) using the highest applicable transfer coefficient

.

Since post

- application risks are not a concern on day 0 (12 hours following applicatio n), the restricted entry interval (REI) is based on the acute toxicity of lactofen technical material.

Lactofen is classified as Toxicity Category III via the dermal route and eye irritation potential and Toxicity Category IV for skin irritation potential

. Under the Worker Protection Standard for Agricultural Pesticides, active ingredients classified as acute toxicity categories III or IV for these routes are assigned a 12

- hour REI. Therefore, the 12

- hour REI that appears on the labels is adequate.

### Page 5 of 19

R esidential Exposure

No residential uses are associated with the use s being evaluated in this action and, therefore, no

residential handler exposure and risk assess ment has been conducted

.

Review of Human Research

This risk assessment relies in part on data from studies in which adult human subjects were intentionally exposed to a pesticide or other chemical. These data, which include studies from PHED 1.1 and the AHETF database are (1) subject to ethics review pur suant to 40 CFR 26, (2) have received that review, and (3) are compliant with applicable 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 guid ance on their use, can be found at http://www.epa.gov/pesticides/science/handler

- exposure

- data.html and http://www.epa.gov/pesticides/science/post

- app

- exposure

- data.html

.

2.0 Hazard Characterization

Lactofen has a low acute toxicity profile based on its classification in Toxicity Cate gory II I via

the dermal r o ute and Toxicity Category IV via the oral and inhalation route s

. It is not a skin sensitizer but it is a very slight dermal irritant. The manufacturing use product (MUP), however, is classified as a moderate eye irritant. Table 1 presents a summary of the acute toxicity

information for l actofen

.

Table 1. Acute Toxicity Profile

– Lactofen

Guideline

No. S tudy Type Accession #(S). Results Toxicity Category

81

- 1 Acute Oral 73859 LD 50 > 5.96 g/kg IV

81

- 2 Acute Dermal 73859 LD 50 > 2.0 g/kg III

81

- 3 Acute Inhalation 73859 LC 50 > 6.3 m/L IV

81

- 4 Primary Eye Irritation (MUP) 73859 Moderate eye irritant III

81

- 5 Primary Skin Irritation

(MUP) 73859 Very slight dermal irritant IV

81

- 6 Dermal Sensitization 73859 Not a dermal sensitizer



### On February 22, 2000 the Health Effects Division (HED) Hazard Identification Assessment
Review Commit tee (HIARC) evaluated the toxicology database for lactofen, re

- assessed the existing reference dose, and selected the doses and toxicological endpoints for dietary and non

dietary exposure risk assessments. Additional data and information have been submitted since

th en, including mechanistic data on the carcinogenicity of lactofen (Fricke 2002) and a request to waive the rabbit developmental study (Phang 2006 ). T he cancer classification of lactofen should
be characterized as “not likel y to be carcinogenic in humans.”

The toxicological points of departure that were used to complete the occupational risk

assessment are summarized below and in Table 2

. Adverse effects were identified at durations

### Page 6 of 19

of exposure ranging from short

- term to intermediate

- term durations. No c ancer endpoint was identified; therefore, cancer risks were not assessed.

Dermal and Inhalation Route (N on

- cancer)

The short

- and intermediate

- term dermal and inhalation risk assessments for lactofen are based

on a L OAEL of 5 mg/kg/day defined in a n oral developmental toxicity study in rabbits

. A NOAEL was not established for this study. No long

- term occupational exp osures are expected

from the uses of lactofen

.

Non

- cancer Level of Concern (LOC)

HED’s level of concern (LOC) for lactofen short

- and intermediate

- term dermal and inhalation exposures is 300 (i.e., an MOE ≥ 300 is not of concern to HED). The LOC is based on a 10X to account for interspecies extrapolation (differences between humans an d animals), a 10X to account for intraspecies sensitivity (differences among humans), and an additional 3X factor to

account for the extrapolation of a lowest observed adverse effect level ( LOAEL ) to NOAEL.

Body Weight

The average adult body weight (8 0 kg) was used for occupational dermal and inhalation risk

assessments because the short

- and intermediate

- term inhalation point of departure was not sex

specific.

Table 2. Summary of Toxicological Doses and Endpoints for Lactofen for Use in Occupational Human Health Risk Assessments
Exposure/
Scenario Point of

Departure Uncertainty

Factors Level of Concern

for Risk

Assessment Study and Toxicological Effects

Dermal Short

Term (1

- 30 days)

and

Intermediate

Term (1

- 6 months) L OAEL = 5

mg/kg/day UF A =10x

UF H =10x

UF L =3X Occupational LOC

is an MOE = 300 Developmental Toxicity Study

– Rabbit

LOAEL was 5 mg/kg based on decrease in live young per litter accompanied by

i ncreases in post

- implantation loss and in early embryonic death/litter.

Inhalation

Short

- Term (1

- 30 days) and

Intermediate

term (1

- 6 months) L OAEL = 5

mg/kg/day UF A =10x

UF H =10x

UF L =3X Occupational LOC

is an MOE = 300 Developmental Toxicity Study

– Rabbit

LOAEL was 5 mg/kg based on decrease in live young per liver a ccompanied by increases in post

- implantation loss and in early embryonic death/litter.

Cancer (oral, dermal, inhalation) Classification: Not likely to be carcinogenic to humans.

1 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. LOAEL = lowest observed adverse effect level. UF = uncertainty factor. UF A = extra polation from animal to human (intraspecies). UF H

### Page 7 of 19

= potential variation in sensitivity among members of the human population (interspecies). 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.



### 3 .0 Use Patterns

Table 3 provides a summary of the registered products with uses on soybeans, snap beans, conifer seedlings, and strawberri es (non

- bearing) for lactofen. Four end

- use product labels were evaluated, including three products formulated as an emulsifiable concentrate ( Cobra ® 

### Herbicide

- EPA Reg. No. 59639

- 34; Stellar ® 

### Herbicide

- EPA Reg. No. 59639

- 92; and V

- 10086

Her bicide EPA Reg. No. 59639

- 118) and one product formulated as a wettable powder in water

soluble packaging ( Cobra ® 

### 25 Herbicide

- EPA Reg. No. 59639

- 113). Additionally, four SLN

labels for Cobra ® 

### Herbicide ( EPA Reg. No. 59639

- 34 ) were evaluated.

Table 4 provides a summary of the use pattern for each of registered uses of lactofen on soybeans, snap beans, conifer seedlings, and strawberries (non

- bearing)

. Maximum single application rates are 0.20 lb ai/A for soybean, 0.25 lb ai/A for snap bean and conifer seedlings, and 0.38 lb ai/A for strawberries (non

- bearing).

Table 3. Summary of End

- Use Products

Product EPA Reg No. Formulation Type a % ai lb ai/gal Crop Use

Cobra ® Herbicide 59639

- 34 EC 24 2 Soybean, Snap Bean, Conifer Seedlings

IA890002 EC 23.2 2 Soybean

NM980003 and

TX980006 EC 23.2 2 Snap Bean

OR010006 EC 23.2 2 Strawberries (non

- bearing)

Stellar ® Herbicide 59639

- 92 EC 26.6 2.4 Soybean

V

- 10086

Herbicide 59639

- 118 EC 24 2 Soybean, Snap Bean

Cobra ® 25

Herbicide 59639

- 113 WP in WSP 25 N/A Soybean

a, EC = emulsifiable concentrate ; WP in WSP = wettable powder i n water

- soluble packaging.



### Table 4 . Summary of Maximum Application Rates for Lactofen Agricultural Uses

Crop Target Formulation Maximum Single Application Rate a Application Equipment

Soybean Foliage EC; WP in WSP 0. 2 0 lb ai/acre Aerial

Ground

Soil EC; WP in WSP 0. 3 0 lb ai/acre Aerial

Ground

Snap Bean Soil EC 0.25 lb ai/acre a Aerial

Ground

Conifers Soil and Seedling EC 0.25 lb ai/acre Ground

### Page 8 of 19

Table 4 . Summary of Maximum Application Rates for Lactofen Agricultural Uses

Crop Target Formulation Maximum Single Application Rate a Application Equipment Transplants (prior to bud break) Handgun

Strawberries (non

bearing) Soil and Transplants

(dormant, with soil placed over crown) EC 0.38 lb ai/acre Aerial

Ground

a

. For the SLN label, the maximum application rate is 0.22 lb ai/A.



### 4.0 Occupational Exposure/Risk

4.1 Occupational Handler

The Agency uses the term “handlers” to describe those individuals who are involved in the pesticide application process. The anticipated use patterns and current labeling indicate occupational exposure scenarios based on the types of equipment and techniq ues that can potentially be used for lactofen applications.

Handlers may apply lactofen to all crops using aerial and groundboom equipment. Applications to conifers may also be a pplied using handgun equipment. Application methods, maximum application rates, and use sites are summarized in Table 4

. Handler exposure is expected to be

short

- or intermediate

- term based on information provided on the labels.

The quantitative exposure/risk assessment for occupational handlers is based on the following exposure scenarios:

Mixer/Loaders

1. Mixing/loading liquid s to support aerial applications

, 2. Mixing/loading liquid s to support groundboom applications

, 3. Mixing/loading wettable powders in water

- soluble packagi ng to support aerial applications

, 4. Mixing/loading wettable powders in water

- soluble packaging to support groundboom applications

,

Applicators

5. Applying sprays with fixed

- wing aircraft (enclosed cockpit)

, 6. Applying sprays with groundboom equipment

,

Flaggers

7. Flagging to support aerial spray applications

, and

Mixer/Loader/Applicator

8. Mixing/loading/applying using mechanically pressurized handgun s prayer

.

### Page 9 of 19 4.1.1 Data and Assumptions for Handler Exposure Scenarios

Unit Exposures

Chemical

- specific data for assessing exposure during pesticide handling activities (mixing/loading, applying, flagging , etc. ) were not submitted to the Agency in support of this

action

. 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 the Pesticide Handlers Exposure Database Version 1.1 (PHED 1.1), the Agricultural Handler Exposure Task Force (AHETF) database, the Outdoor Residential Exposure Task Force (ORETF) database, or other registrant

- submitted occupational exposure studies. Some 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” ( http:/ /www.epa.gov/opp00001/science/handler

- exposure

table.pdf ) , which, along with additional information on HED policy on use of surrogate data, including descriptions of the various sources, can be found at http://www.epa.gov/pesticides/science/handler

- exposure

- data.html

.

Risk Mitigation Approach

The baseline clothing level for occupational exposure scenarios represents an individual wearing long pants, a long

- sleeved shirt, shoes, socks, no chemical

- resistant gloves, and no respirator. The first level of mitigation applied is personal protective equipment (PPE), which may include

addition of chemical

- resistant gloves (as specified on current label ing ), an additional layer of

cloth ing, and/or a respirator. The next step in mitigation considered in the risk assessment process is the use of appropriate engineering controls. Examples of commonly used engineering

controls include enclosed cockpits or tractor cabs, closed mixing/loadin g systems, and water

soluble packets.

Occupation al handler exposure assessments of lactofen use were completed using baseline clothing, baseline clothing plus gloves, closed mixing/loading systems for the EC formulations,

water

- soluble packets for the wet table powder formulation, and enclosed cockpits for aerial applications.

Area Treated

Based on HED Exposure Science Advisory Committee SOP N o. 9.1, the area treated in a day is

assumed to be:

1,200 acres for aerial treatments for soybean ; 350 acres for aerial treatments for snap beans, conifer seedlings, and strawberries (non

bearing) ;

### Page 10 of 19

200 acres for groundboom applications for soybean ; 80 acres for groundboom applications for snap beans, conifer seedlings, and strawberries (non

- bearing) ; 350 acres for flagging for aerial treatments (all crops) ; and

20 acres for mechanically pressurized handgun s prayer treatments for conifers.

Application Rate

Broadcast f

oliar applications of lactofen may be applied at a maximum application rate of 0.3 0 lb ai/A for soybean, 0.25 lb ai/A for snap bean and conifer seedlings, and 0.38 lb ai/A for strawberries (non

- bearing). Application rates are shown in Table 4

.

Body Weight

Th e average adult body weight of 8 0 kg was used for estimating dermal and inhalation dose s , since the selected toxicological endpoints are not sex

- specific

.

Absorption Factor s

S ince the short

- and intermediate

- term dermal and inhalation PoD was based on a n oral developmental study, a dermal absorption factor of 20 % was used to estimate dermal exposure

for short

- and intermediate

- term durations. Since no inhalation absorption data are available, toxicity by the inhalation route is considered to be equivalent to the estimated toxicity by the oral route of exposure

.

Equations and Calculations

Daily Exposure: Daily handler exposures are estimated for each applicable handler task with the application rate, the amount of acres treated in a day, and the applicable unit exposure using the following formula:

Daily Exposure (mg ai/day) =

Unit Exposure (mg or μg ai/lb ai) x Applicat ion Rate (lb ai/A) x Daily Area Treated (A/day)

Where:

Daily Exposure = Amount (mg ai/day) deposited on the surface of the skin that is available for dermal absorption or amount inhaled that is available for inhalation absorption; Unit Exposure = Unit exposure value (mg or μg ai/lb ai) derived from exposure data; Application Rate = Normalized application rate based on a logical unit treatment, such as acres, square feet, or gallons. Maximum values are generally used (lb ai/A) and Daily Area Treated = Normalized application area based on a logical unit treatment

### Page 11 of 19 such as acres (A/day)

.



### Daily Dose: Daily dose (inhalation or dermal) was calculated by normalizing the daily de rmal or inhalation exposure value by body weight and accounting for dermal and i nhalation absorption. Average Daily Dose (mg ai/kg/day) = Daily Exposure (mg ai/day) x ( Absorption Factor (%/100 ) Body Weight (kg)

Where:

Average Daily Dose = Absorbed dose received from exposure to a pesticide in a given scenario (mg pesticide active ingredient/kg body weight/day); Daily Exposure = Amount (mg ai/day) deposited on the surface of the skin that is available for dermal absorption or am ount inhaled that is available for inhalation absorption; Absorption Factor = A measure of the amount of chemical that crosses a biological boundary such as the skin or lungs (% of the total available absorbed); and Body Weight = Body weight determined to represent the population of interest in a risk assessment (kg).



### Margin of Exposure (MOE): The daily dermal dose and daily inhalation dose received by occupational handlers w ere compared to the appropriate point of departure (i.e., NOAEL) to assess the risk to occupational handlers for each exposure route. All MOE values were calculated separately for dermal and inhalation exposure levels using the following formula:

MOE = NOAEL or LOAEL (mg ai/ (kg/day)) Average Daily Dose (mg ai/ (kg/day))

Where:

MOE = Margin of Exposure, value used by HED to represent risk or how close a chemical exposure is to being a concern (unitless);

ADD = Average Daily Dose or the absorbed dose received from exposure to a pesticide i n a given scenario (mg pesticide active ingredient/kg body weight/day); and

NOAEL or LOAEL = Dose level in a toxicity study, where no observed adverse effects (NOAEL) or where the lowest observed adverse effects (LOAEL) occurred in the study



### Combined Risks: Dermal and inhalation risks for short

- and intermediate

- term risks were combined in this assessment, since the toxicological effects for the dermal and inhalations routes

were the same. Dermal and inhalation risks were combined using the following formula:

Total MOE = 1/ ((1/ Dermal MOE) + (1/Inhalation MOE))



### 4.1.2 Occupational Handler and Exposure Risk Summary

Summaries of the risks for occupational handlers are included in Table 5 . The maximum application rate for each exposure scenario is presented as the worst

- case scenario. None of the

### Page 12 of 19

occupational handler exposure scenarios assessed result in combined dermal and inhalation risks of concern (i.e., an MOE ≥ 300) at either basel ine attire, with the addition of chemical

- resistant gloves, and/or engineering controls.

### Page 13 of 19 Table 5

. Short

- and Intermdiate

- term Agricultural Handler Risk Estimates for Lactofen

Exposure Scenario Crop or Target Application

Rate a (lb ai/A) Area

Treated Daily b
(acres) Unit Exposure c,d,e

( μ g/lb ai) Dose f,g
(mg/kg/day) MOEs h,i,j,k

Baseline

Dermal PPE

- G

Dermal Baseline

Inhalation Baseline

Dermal d,h PPE

- G

Dermal i Baseline

Inhalation e Baseline

Dermal f PPE

- G

Dermal Baseline

Inhalation g Combined

Baseline

Dermal +

Inhalation

j Combined

PPE

- G
Dermal +

Inhalation

j k

Mixer/Loader

Mixing/Loading Liquid s for Aerial Applications S oybean 0.3 0 1

, 200 220 37.6 [ eng. control = 8.6 ] 0.219

[eng.
control= 0.083] 0.20 0.034

[ eng. control = 0.0077 ] 0.000 20

[eng.
control = 0.0000 75] 25 150 [ eng. control = 650 ] 26

, 000

[eng.
control =

67

, 000 ] 25 15 0 [ eng. control = 640 ] Snap Bean
and Conifer Seedlings 0.25 350 220 37.6 0.219 0.048 0.0082 0.000048 100 610 100

, 000 100 61 0

Strawberries (non

bearing) 0.38 350 220 37.6 0.219 0.0 73 0.01 3 0.00007 3 70 400 69

, 000 70 400

Mixing/Loading Liquids
for Groundboom Applications S oybean 0.3 0 200 220 37.6 0.219 0.03 3 0.00 56 0.00003 3 1 50 890 1 5 0

, 000 1 5 0 89 0

Snap Bean
and Conifer Seedlings 0.25 80 220 37.6 0.219 0.01 1 0.00 19 0.00001 1 4 50 2

, 7 00 46 0

, 000 45 0 2

, 7 00

Strawberries (non

bearing) 0.38 80 220 37.6 0.219 0.01 7 0.00 29 0.00001 7 300 1

, 7 00 300

, 000 300 1

, 7 00

Mixing/Loading

Wettable Powders in

Water

- Soluble Packaging for Aerial Applications S oybean 0.3 0 1

, 200 NA 9.8 (eng. control) 0.24

(eng. control) NA 0.088 (eng. control) 0.00022

(eng. control) NA 5 7 0 (eng. control) 23

, 000

(eng. control) NA 570 (eng. control)

Mixing/Loading
Wettable Powders in
Water Soluble Packaging for
Groundboom Applications S oybean 0.3 0 200 NA 9.8 (eng. control) 0.24

(eng. control) NA 0.0015 (eng. control) 0.000036

(eng. control) NA 3

, 4 00 (eng. control) 14 0

, 000

(eng. control) NA 3,4 00 (eng. control)

### Page 14 of 19 Table 5

. Short

- and Intermdiate

- term Agricultural Handler Risk Estimates for Lactofen

Exposure Scenario Crop or Target Application

Rate a (lb ai/A) Area

Treated Daily b
(acres) Unit Exposure c,d,e

( μ g/lb ai) Dose f,g
(mg/kg/day) MOEs h,i,j,k

Baseline

Dermal PPE

- G

Dermal Baseline

Inhalation Baseline

Dermal d,h PPE

- G

Dermal i Baseline

Inhalation e Baseline

Dermal f PPE

- G

Dermal Baseline

Inhalation g Combined

Baseline

Dermal +

Inhalation

j Combined

PPE

- G
Dermal +

Inhalation

j k

Applicator

Applying Sprays via

Fixed

- Wing Aerial Equipment (Enclosed Cockpit) S oybean 0.3 0 1

, 200 5 .0 (eng. control) No Data 0.068

(eng. control) 0.0045

(eng. control) No Data 0.000061

(eng. control) 1,100

(eng. control) No Data 82

, 000

(eng. control) No Data 1,100 (eng. control)

Snap Bean 0.25 350 5 .0 (eng. control) No Data 0.068

(eng. control) 0.0011

(eng. control) No Data 0.000015

(eng. control) 4

, 6 00

(eng. control) No Data 34 0

, 000

(eng. control) No Data 4,6 00 (eng. control)

Strawberries (non

bearing) 0.38 350 5 .0 (eng. control) No Data 0.068

(eng. control) 0.001 7

(eng. control) No Data 0.000023

(eng. control) 3

, 0 00

(eng. control) No Data 22 0

, 000

(eng. control) No Data 3,0 00 (eng. control)

Applying Sprays via Groundboom Equipment (Open Cab) S oybean 0.3 0 200 78.6 16.1 0.34 0.01 2 0.002 4 0.00005 1 420 2

, 1 00 98

, 000 420 2,1 00

Snap Bean
and Conifer Seedlings 0.25 80 78.6 16.1 0.34 0.00 39 0.000 81 0.00001 7 1

, 3 00 6,2 00 29 0

, 000 1

, 3 00 6,2 00

Strawberries (non

bearing) 0.38 80 78.6 16.1 0.34 0.006 0 0.001 2 0.0000 26 840 4,1 00 19 0

, 000 840 4,1 00

Flagger

Flagging for Aerial Sprays Applications S oybean 0.3 0 350 11 NA 0.35 0.00 29 NA 0.000 092 1

, 7 00 NA 54

, 000 1

, 7 00 NA

Snap Bean 0.25 350 11 NA 0.35 0.002 4 NA 0.0000 77 2

, 0 00 NA 65

, 000 2,0 00 NA

Strawberries (non

bearing) 0.38 350 11 NA 0.35 0.00 37 NA 0.0001 2 1

, 4 00 NA 43

, 000 1

, 3 00 NA

### Page 15 of 19 Table 5

. Short

- and Intermdiate

- term Agricultural Handler Risk Estimates for Lactofen

Exposure Scenario Crop or Target Application

Rate a (lb ai/A) Area

Treated Daily b
(acres) Unit Exposure c,d,e

( μ g/lb ai) Dose f,g
(mg/kg/day) MOEs h,i,j,k

Baseline

Dermal PPE

- G

Dermal Baseline

Inhalation Baseline

Dermal d,h PPE

- G

Dermal i Baseline

Inhalation e Baseline

Dermal f PPE

- G

Dermal Baseline

Inhalation g Combined

Baseline

Dermal +

Inhalation

j Combined

PPE

- G
Dermal +

Inhalation

j k

Mixer/Loader/Applicator
Mixing/Loading/ Applying Mechanically Pressurized Handgun Sprayer Conifer

Seedlings 0.25 2 0 1,300 390 3.9 0.0 16 0.00 49 0.0000 0 49 310 1,000 100 ,000 310 1,000

a. Application rates = maximum application rates from labels.

b. Area treated daily from Science Advisory Council Policy # 9.1

. c. Unit Exposures are from the “Occupational Pesticide Handler Unit Exposure Surrogate Reference Table,” dated 9/26/11, and located at http://www.epa.gov/opp00001/science/handler

- exposure

- table.pdf

. Enginee ring control unit exposure for mixing/loading liquids = closed system. Engineering control unit exposure for applying sprays via aerial equipment = enclosed cockpit. Engineering control unit exposure for mixing/loading wettable powders = water

- soluble pa ckaging.

d. Baseline Dermal = Long

- sleeve shirt, long pants, and no gloves; Baseline Inhalation: no respirator.

e. PPE

- G = Baseline plus chemical

- resistant gloves; f. Dermal Dose (mg/kg/day) = daily unit exposure (mg/lb ai) x application rate (lb ai /acre) x acres treated x dermal absorption factor (20 %) / body weight (8 0 kg adult). g. Inhalation Dose (mg/kg/day) daily unit exposure (μg/lb ai) x application rate (lb ai/acre) x acres treated x inhalation ab sorption (100%) / body weight (8 0 kg adult). h. Dermal MOE = NOAEL (3.0 mg/kg/day) / dermal daily dose (mg/kg/day). Level of concern = 3 00. Bold = MOE ≤ 300

. i. Inhalation MOE = NOAEL (3.0 mg/kg/day) / inhalation daily dose ( mg/kg/day). Level of concern = 3 00. Bold = MOE ≤ 300

. j. Combined Baseline Dermal + Inhalation MOE = 1 / (1/Baseline Dermal MOE) + (1/Baseline Inhalation MOE). Bold = MOE ≤ 300

. k. Combined PPE

- G + Baseline Inhalation MOE = 1 / (1/PPE

- G Dermal MOE) + (1/Baseline Inhalation MOE). Bold = MOE ≤ 300

.

### Page 16 of 19

4.2 Post

- application Exposure

4.2.1 Data and Assumptions for Post

- application Exposure Scenarios

Inhalation: Based on the Agency's current practices, a quantitative post

- application inhalation exposure assessment was not performed for the uses of lactofen at this time primarily because it has low vapor pressure ( 2.8 x 10

- 7 mm Hg )

. However, volatilization of pesticides may be a potential source of post

- application inhalation exposure to individuals nearby to pesticide applications. The Agency sought expert advice and input on issues related to volatilization of pesticides from its Federal Insecticide, Fungicide, and Rodenticide Act Scientific Advisory Panel (SAP) in December 2009. T he Agency received the SAP’s final report on March 2, 2010 ( http://www.epa.gov/scipoly/SAP/meetings/2009/120109meeting.html ). The Agency is in the process of evaluating the SAP report and may, as appropriate, develop policies and procedures to identify th e need for and, subsequently, the way to incorporate post

- application inhalation exposure into the Agency's risk assessments. If new policies or procedures are put into place, the Agency may revisit the need for a quantitative post

- application inhalation exposure assessment
for indaziflam.

Dermal: There is the possibility for agricultural workers to have post

- application dermal exposure to lactofen following use on soybeans and conifer seedling s

. Post

- application exposures for soybean are not assessed in this action, however, because the exposure is anticipated to be similar to that previously assessed for peanut. Post

- application exposures are considered to be negligible for the use of lactofen on snap beans and strawberr y (non

- bearing)

based on label instructions

. For snap beans, lactofen is applied to the soil only and for strawberries, lactofen is applied to either to the soil or to dormant seedlings with soil placed over the crown prior to application. HED as sumes that post

- application dermal exposure to treated soil by occupational workers is negligible and, t herefore

, post

- application exposures and risks to occupational workers for the snap bean and strawberry uses were not quantitatively assessed.

The as sumptions made in assessing the s hort

- and intermediate

- te rm dermal post

- application

risks for the use of lactofen on c onifer seedlings include the application rate, bodyweight, and dermal absorption factor values discussed above in the occupational handle r section, and the following assumptions below:

Dislodgeable foliar residues

There were no chemical

- specific dislodgeable foliar residue data to assess post

- application risks to workers while performing tasks related to crops treated with lactofen . Occupational post

application exposures and risks are assessed using H ED’s default assumptions that 25 % of the initial application is available for transfer on day 0 (i.e., 12 hours after application)

, and that the residue dissipates at a rate of 10 % per day.

Transfer coefficients

Transfer coefficients numerically represent the post

- application exposures one would receive (generally presented as cm 2 

### /hour). A transfer coefficient is a measure of the residue transferred

### Page 17 of 19

from a treated surface to a person who is doing a task or activity in a treated area. These values are the ratio of an exposure for a given task or activity to the amount of pesticide residue on
treated surfaces available for transfer.

It is the policy of HED to use the best available data to assess post

- application exposure. The TC values recommended for use in predicting post

- application exposure are presented in the “Science Advisory Council for Exposure (ExpoSAC) Policy 3” ( http://www.epa.gov/pesticides/science/exposac_policy3.pdf ), which, can be found at http://www.epa.gov/pesticides/science/post

- app

- exposure

- data.html

.

HED selects the most appropriate TCs based on the label use patterns for the crops. HED

assessed post

- application exposure to conifers (seedlings and conifers in nurseries) using a transfer coefficient of 580 for scouting Christmas t rees (low height foliage and minimum density foliage). HED did not select a TC for irrigation activities because the only irrigation transfer coefficient available for Christmas trees is for full foliage density, which is not rep resentative of the use pat tern.

The TC for sod harvesting , 6,700, was s elected as it was determined to be most similar to the
activit y of harvesting and bundling conifer seedlings. When using the sod harvesting TC, the fraction application rate retained on foliage (DFR) is anticipated to be 1%

, which is consistent
with that recommended for the assessment of liquid formulated turf products.

Workday

HED assumes an 8 hour workday for post

- application workers

.

Equations and Calculations

Daily D ermal E

xposure: Daily dermal exposures were calculated on each post

- application day after application using the following equation:

E (t) 

### (mg/day) = (DFR (t) 

### (μg/cm 2 

### ) x TC (cm 2 

### /hr) x Hr/Day)/1,000 (μg/mg)

Where:

E(t) = Daily exposure or amount deposited on the surface of the skin at time (t)

attributable for activity in a previously treated area ; DFR(t) = Dislodgeable foliar residue at time “t” (μg/cm 2 ) ; TC = Transfer Coefficient (cm 2 /hour) ; and Hr/day = Exposure duration meant to repres ent a typical workday ( 8 hours).



### DFR: Default dislodgeable foliar residue (DFR) values were calculated on each post

- application day after application using the following equation:

DFR (μg/cm 2 

### ) = AR (lb ai/A) x F x (1

- D) t 

### x CF1 x CF2

### Page 18 of 19 Where:

AR = Maximum application rate;
F = Fractio n of ai retained on the foliage;

D = Fraction o f residue that dissipates daily;

t = Post

- application day ; CF1 = 4.54E+8 μg/lb ; and

CF2 = 2.47E

- 8 A/cm 2

.



### 4.2.2 Post

- application Exposure and Risk

The post

- application exposure associated with conifer seedlings is summarized in Table 6

. Using HED default assumptions and surrogate DFR data, risks were not of concern (i.e., MOEs ≥ 300) on Day 0 (12 h ou rs after application ) using the highest transfer coefficient

.

Table 6

. Post

- application Exposure and Risk for Lactofen

Crop TC a Days after

Treatment DFR b (μg/cm 2 ) Daily Dermal Dose c (mg/kg/day) MOE d

Conifer Seedlings 580 (scouting) 0

(12 hours) 0. 63 0.00 73 680

6,7 00 (harvesting ) e 0

(12 hours) 0. 025 0.0 034 1,500

a

. Transfer coefficients from “Science Advisory Council for Exposure (ExpoSAC) Policy 3” http://www.epa.gov/pesticides/science/exposac_policy3.pdf)

b

. DFR = Dislodgeable Foliar Residue = application rate (lb ai/A) x (1

- daily dissipation rate) t x 4.54E8 μg/l b x 2.47E

- 8 A/cm 2 x 25 % DFR after initial treatment or 1% turf transferable residue (TTR) after initial treatment (for use with sod harvesting TC)

c

. Daily Dermal Dose = [DFR (μg/cm 2 ) x Tc (cm 2 /hr) x 0.001 mg/μg x dermal absorption (20 %) * 8 hrs/day] body weight (8 0 kg adult)

d

. MOE = L OAEL/Daily Dose (Dermal NOAEL = 5 mg/kg/day)

e. The TC for sod harvesting was s elected from “Science Advisory Council for Exposure (ExpoSAC) Policy 3 ” which was

determined to be most similar to the activity of h arvesting and bundling conifer seedlings.



### Restricted Entry Interval: Since post

- application risks are not a concern on day 0 (12 hours following application), the restricted entry interval (REI) is based on the acute toxicity of

lactofen technical material. Lactofen is classified as Toxicity Category III via the dermal route and for eye irritation potential and as Toxicity Category IV for skin irritation potential. Under the Worker Protection Standard for Agricultural Pesticides, active ingredients classified as acute toxicity categories III or IV for these routes are assigned a 12

- hour REI. Therefore, the 12

- hour REI that appears on the labels is adequate.

5.0 Residential (Non

- Occupational) Exposure and Risk

No residential uses are a ssociated with the uses of lactofen being evaluated in this action and, therefore, no residential handler exposure and risk assessment has been conducted in this

document.

Residential Bystander Post

- Application Inhalation Exposure

### Page 19 of 19

Based on the Agency's current practices, a quantitative post

- application inhalation exposure assessment was not performed for lactofen at this time because of the low acute inhalation toxicity (Toxicity Category IV), low vapor pressure (3.0 × 10

- 8 mm Hg at 21 oC ) , and the low application rates (0.20 to 0.38 lb ai/A)

. However, volatilization of pesticides may be a potential source of post

- application inhalation exposure to individuals nearby to pesticide applications. The Agency sought expert advice and input on issues related to volatilization of pesticides from its Federal Insecticide, Fungicide, and Rodenticide Act Scientific Advisory Panel (SAP) in December 2009, and received the SAP’s final report on March 2, 2010 ( http://www.epa.gov/scipoly/SAP/meetings/2009/120109meeting.html ). The Agency is in the process of evaluating the SAP report and may, as appropriate, develop policies and procedures to identify the need for and, subsequently, the way to incorporate post

- application inhalation exposure into the Agency's risk assessments. If new policies or procedures are developed, the Agency may revisit the need for a quantitative post

- application inhalation exposure assessment

for lactofen.

Spray Drif

t

Spray drift is always a potential source of exposure to residents nearby to spraying operations. This is particularly the case with aerial application, but, to a lesser extent, could also be a potential source of exposure from the ground application method employed for lactofen . The Agency has been working with the Spray Drift Task Force, EPA Regional Offices and State Lead Agencies for pesticide regulation and other parties to develop the best spray drift management practices (see the Agency’s Spray Drift website for more information at http://www.epa.gov/opp00001/factsheets/spraydrift.htm ). On a chemical by chemical basis, the Agency is now requiring interim mitigation measures for aerial applications that must be placed on product labels/labeling. The Agency has completed its evaluation of the new database submitted by the Spray Drift Task Force, a membership of U.S. pesticide registrants, and is developing a policy on how to appr opriately apply the data and the AgDRIFT computer model to its risk assessments for pesticides applied by air, orchard airblast and ground hydraulic methods. After the policy is in place, the Agency may impose further refinements in spray drift
management practices to reduce off

- target drift with specific products with significant risk
estimates associated with drift.

Although a quantitative residential post

- application inhalation exposure assessment was not performed as a result of pesticide drift from n eighboring treated agricultural fields, an inhalation exposure assessment was performed for flaggers. This exposure scenario is representative of a worse case inhalation (drift) exposure and may be considered protective of most outdoor agricultural and co mmercial post

- application inhalation exposure scenarios

.