Page 1 of 60 

### UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON, D.C. 20460

OFFICE OF CHEMICAL SAFETY

AND POLLUTION PREVENTION



### Date : November 9 , 2015

Subject: Boric Acid /Sodium Salts of Boric Acid

. Occupational and Residential Exposure

and Risk Assessment for Registration Review

.

PC Code: 011101, 011102, 011103, 011104, 011107, 011110, 011111, 011112, 011002 DP Barcode: D 428582, D320890, D320888, D320728

Decision Number: 48 8334 ,359976,359975,359928 Registration Number: N/A

Petition Number: NA Regulatory Action: Registration Review Risk Assessment Type: NA Case Number: 0024

T XR Number: NA CAS Number: 10043

- 35

- 3, 1303

- 96

- 4, 1130

- 12

- 4,

12179

- 04

- 3, 1330

- 43

- 4, 12008

- 41

- 2, 15293

- 77

- 3, 1303

- 86

- 2

MRID Numbers: 46852202, 47579901 , 47579902,

46971101 40CFR: §180 .1121 (Active Ingredient); §180 .920 (Inert Ingredient)



### From: Matthew Crowley

, Biolog ist

Risk Assessment Branch 2 (RAB 2 ) Health Effects Division ( HED; 7509P)

Through: Christina Swartz

, Branch Chief

Risk Assessment Branch 2 (RAB2) Health Effects Division (HED; 7509P)

and

Kelly O’Rourke , Reviewer

James

- S Miller , Reviewer Exposure Science Advisory Committee (ExpoSAC) / HED

To: Moana Appleyard, Chemical Review Manager

Risk Management and Implementation Branch 5 (RMIB 5 )

Pesticide Re

- evaluation Division (PRD)

As part of Registration Review, the Pesticide Re

- evaluation Division (PRD) of EPA’s Office of Pesticide Programs ( OPP ) has requested that the Health Effects Division ( HED ) evaluate the hazard and exposure data and conduct occupational and residential expos ure assessments, as needed, to estimate the risk to human health that will result from the currently registered uses of pesticides. This memorandum serves as HED’s Registration Review assessment of thePage 2 of 60



### occupational and residential handler and post

- applica tion exposure and risk from the current ly registered uses of boric acid and its sodium salts

.

It is HED policy to use the best available data to assess exposure. Several sources of generic data were used in this assessment as surrogate data in the abse nce of chemical

- specific data, including 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 ; the Residential SOPs (Law ns/Turf, Indoor Environments); and other registrant

- submitted exposure studies (MRIDs 44339801, 45250702, 45333401, 44439901, 45519601, 45167201, 43600102) . Some of these data are proprietary, and subject to the data protection provisions of the Federal I nsecticide, Fungicide, and Rodenticide Act ( FIFRA).

Note: This memorandum was reviewed by the Exposure Science Advisory Committee (ExpoSAC) on 10

- SEP

- 2015

.Page 3 of 60 

### Table of Contents

1.0 Executive Summary

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

2.0 Risk Assessment Conclusions and Recommendations

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

2.1 Summary of Risk Estimates

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

2.2 Label Recommendations

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

2.3 Data Deficiencies and Requirements

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

3.0 Hazard Characterization

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

4. 0 Exposure and Use Profile

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

5.0 Residential Exposure and Risk Estimates

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

5.1 Residential Handler Exposure/Risk Estimates

................................ ............................... 17

5.2 Residential Post

- application Exposure/Risk Estimates

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

5.3 Residential Risk Estimates for Use in Aggregate Assessment

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

6.0 Non

- Occupational Spray Drift Exposure and Risk Estimates

................................ .......... 28

7.0 Non

- Occupational Bystander Post

- Application Inhalation Exposure and Risk Estimates 29

8.0 Occupational Exposure and Risk Estimates

................................ ................................ ..... 30

8.1 Occupational Handler Exposure/Risk Estimates

................................ ............................ 30

8.2 Occupational Post

- application Exposure/Risk Estimates

................................ .............. 41

8.2.1 Occupational Post

- application Inhalation Exposure/Risk Estimates

...................... 41

8.2.2 Occupational Post

- application Dermal Exposure/Risk Estimates

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

- cancer Algorithms

..................... 43Page 4 of 60



### 1.0 Executive Summary

Boric acid [H 3 

### BO 3 

### ] and its sodium salts (sodium tetraborate decahydrate, sodium tetraborate pentahydrate, sodium tetraborate anhydrous, disodium octaborate tetrahydrate, disodium octaborate anhydrous and sodium metaborate) are active ingredients in a wide variety of pestici des including insecticides, acaricides, herbicides, algaecides, fungicides and wood preservatives. This document assesses occupational and residential exposures and risk es timates from the registered conventional use s of boric acid and its sodium salts re quired during Registration Review

. Exposure and risk estimates for antimicrobial uses of boric acid and its sodium salts (e.g., wood preservatives, swimming pools, etc.) are addressed in a separate

assessment.

For purposes of risk assessment, exposure an d toxicity are expressed in terms of boron equivalents, with molecular weight conversions to boron from boric acid or a borate sodium salt accordingly.

U se and Exposure Profile

There are numerous pesticide products containing boric acid or its sodium salts as the active ingredient used in residential, commercial, and agricultural settings . Products are both liquid and solid formulations ranging from < 1% to 100% active ingredient . Products used in residential settings (e.g., dusts in homes, crack and crevice sprays, recreational parks), commercial/industrial areas (e.g., food handling establishments, airport runways, sewers, transport vehicles) and agricultural facilities (e.g., poultry houses) are applied via hand dispersal, handheld equipment and by vehicles. Products used on agricultural crops are applied via handheld sprays or by vehicles; c hemigation and aerial applications are prohibited.

Based on the registered use pattern for boric acid/sodium salts, dermal and inhalation exposures

are antici pated for both occupational and residential handlers (mixer/loaders, applicators, etc.). In addition, post

- application exposures are also possible, including dermal exposures to re

- entry field workers, and dermal and incidental oral exposures to children playing on treated grass

. Additionally, dermal exposure to adults and children and incidental oral exposure to children via spray drift on to residential areas resulting from crop applications are expected

.

Hazard Profile and Dose Response

The toxicity database has been updated since previous assessments and is considered complete for the purposes of human health risk assessment.

Boric acid/borate salts generally show low acute lethality by all routes (Toxicity Categories III or

IV )

. Acute d ermal and eye irritation potential vary among the different compounds. For example, sodium tetraborate decahydrate is Category I for eye irritation and IV for skin irritation, while boric acid is Category III for both.

F or short

- /intermediate

- term inhalation and incidental oral exposure, a No Observed Adverse Effect Level ( NOA E L ) of 8.8 mg/kg bw/day was selected based on hematological and testicularPage 5 of 60



### effects observed in both a subchronic and chronic dog feeding study

. All values are expressed in

terms of boron.

The standard body weight for the general population (80 kg) was used for all exposure scenarios covered in this risk assessment since the endpoints selected were not developmental and/or fetal

effects. For assessment of incidental oral exposures to child ren a body weight of 11 kg was

used.

Dermal absorption data in humans indicates negligible absorption (estimated at less than 1%) and is consistent with published reports in laboratory animals showing low or no absorption of

boric acid or borate salts. Adjustment of the no observed adverse effect level (NOAEL) from the most sensitive oral doses for absorption of 1% would yield a dermal dose approaching the limit

dose (1000 mg/kg bw/day )

. Therefore, though dermal exposure is possible, due to the very

li mited absorption of boric acid and its sodium salts, dermal toxicity was not identified and a point of departure was not selected

.

Inhalation and incidental oral r isk estimates are combined where applicable due to use of the same toxicological endpoint. For both exposure scenarios, uncertainty factors (UFs) of 10x for interspecies (UF A 

### )

, 10x for intraspecies (UF H 

### ) variation , and 1x for the F ood Q uality P rotection

A ct (FQPA) safety factor (total UF of 100x) were used, thus characterization of risk estimates, in the form of Margins of Exposure (MOEs) are based on a level of 100.

Boric acid/sodium borate salts are classified as “Not Likely to be Carcinogenic to Humans.” A quantitative cancer risk assessment is not required

.

Residential Exposure and Risk

Many products, both applied as liquid sprays/solutions and as solids (dusts or granules), are used in residential settings. Dermal and inhalation exposures are possible during application and dermal, inhalation, and post

- application inc idental oral exposures are possible following applications.

Only post

- application incidental oral risk estimates were of concern for broadcast spray treatments to carpets . All other handler and post

- application risk estimates were not of concern

.

The re commended scenario for the adult a ggregate assessment is inhalation exposure during applications of dusts/powders to indoor residential areas via a shaker can. The recommended residential exposure s for use in a children 1<2 years old aggregate assessment reflects the combined exposures from post

- application inhalation and hand

- to

- mouth exposures following

ge neral indoor liquid applications to hard floors.

Spray drift

A quantitative non

- occupational spray drift assessment was not conducted as the direct spray use on home lawn s results in higher exposures than those resulting from spray drift on residentialPage 6 of 60



### areas resulting from agricultural uses. No risks of concern were identified resulting from the direct spray lawn use.

Occupational Exposure and Risk

Occupational risk estimates are based on inhalation exposures only due to the lack of toxicity via the dermal route. Occupational i nhalation handler risk estimates were of concern for a number of scenarios, requiring res piratory protection to mitigate risks. In a few cases, standard respiratory protection measures do not appear to be successful in mitigating inhalation risk

estimates of concern

.

Labels vary considerably with respect to requirements for work attire and p ersonal protective equipment (PPE) and restricted entry intervals (REIs). Label corrections/revisions should be consistently made to default to end

- use product and/or technical grade active ingredient acute (ocular, dermal, oral, and inhalation) toxicity requirements. Additional PPE, such as respiratory protection, beyond end

- use product acute toxicity requirements, should be considered as described in the context of any risks of concern identified in this assessment.

Human Studies Review

This risk asse ssment relies in part on data from studies in which adult human subjects were intentionally exposed to a pesticide or other chemical. These data, which inc lude studies from

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; the Residential SOPs (Lawns/Turf, Indoor Environments); and other registrant

- submitted exposure studies (MRIDs 44339801, 45250702, 45333401, 4443990 1, 45519601, 45167201, 43600102) are (1) subject to ethics review pursuant 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 guidance on their use, can be found at the Agency

website 1



### .

2.0 Risk Assessment Conclusions and Recommendations

2.1 Summary of Risk Estimates

 As no systemic dermal toxicity was identified, occupational and residential dermal exposure/risk assessment were not conducted. However, label requirements based on acute dermal toxicity categories for the active ingredients as well as the end use products

should be evaluated and considere d for label revisions.

 Residential handler inhalation risk estimates were not of concern.

 Post

- application residential incidental oral risk estimates were of concern for broadcast spray treatments to carpets (MOEs < 100). As a result, post

- application c ombined

1 http://www.epa.gov/pesticides/science/handler

- exposure

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

- app

- exposure

- data.htmlPage 7 of 60



### inhalation and incidental oral risk estimates were also of concern for spray treatments to carpets (MOEs < 100) . P ost

- application inhalation risk estimates alone were not of

concern.

 Occupational h andler inhalation risk estimates were of concern f or a number of scenarios, requiring respiratory protection to mitigate risks. In a few cases, standard respiratory protection measures do not appear to be successful in mitigating inhalation risk estimates

of concern.

2.2 Label Recommendations

Labels vary considerably with respect to requirements for work attire and personal protective equipment (PPE). For example, some labels do not specify any requirements for work attire, while others require respirators and coveralls over long

- sleeve shirt and long pants. Similarly

, restricted entry intervals (REIs) also vary considerably across labels (e.g., 4 hours versus 48 hours).

Thus, l abel corrections/revisions should be consistently made to default to end

- use product and/or technical grade active i ngredient acute (ocular, dermal, oral, and inhalation) toxicity requirements. These requirements may vary since each borate sodium salt might have a different acute toxicity profile, in addition to the potential presence of other active ingredients in a

p roduct. In particular, 4 hour REIs should be evaluated in the context of Pesticide Registration (PR) Notice 95

- 3 (see Section 8.2.2). Due to sodium tetraborate decahydrate being acute toxicity category I for eye irritation, the 4 hour may not be appropri ate for this active ingredient class.

Additional PPE, such as respiratory protection, beyond end

- use product acute toxicity requirements, should be considered as described in the context of any risks of concern identified

in this assessment.

2.3 Data Def

iciencies and Requirements

The exposure database is sufficient to support Registration Review of boric acid and its sodium salts and any data requirements have been satisfied.

3 .0 Hazard Characterization

Acute Toxicity

Boric acid/borate salts generally show low acute toxicity by oral and dermal routes (Toxicity Categories III or IV). Boric acid is Category III for acute inhalation, due to limitations in generating test atmosphere concentrations and not mortality (none observed). Dermal and ey e acute irritation potential vary. Sodium tetraborate decahydrate (borax) is Category I for eye irritation and IV for skin irritation, while boric acid is Category III for both.

Table 3.1 .a. Acute Toxicity Profile

- Boric Acid

Guideline No. Study Type MRID(s) Results Toxicity CategoryPage 8 of 60

870.1100 Acute oral rat 00006719 LD 50 males = 3450 mg/kg females = 4080 mg/kg III

870.1100 Acute oral beagle dog 00064208 LD 50 > 631 mg/kg III

870.1200 Acute dermal rabbit 00106011 LD 50 >2 g/kg III

870.1300 Acute inhalation rat 43500701 LC 50 >2.03 mg/L (no
deaths) 1 III

870.2400 Acute eye irritation rabbit 00064209 Conjunctival irritation clearing by Day 4 III

870.2500 Acute dermal irritation rabbit 00106011 Primary irritation score = 0.1; 1/6 erythema at 72

hrs III

1 exposure levels were limited by inability to produce higher test atmosphere concentrations

Table 3. 1.b. Acute Toxicity Profile

- Sodium tetraborate decahydrate (Borax)

Guideline No. Study Type MRID(s) Results Toxicity Category

870.1100 Acute oral rat 40692303 LD 50 males = 4550 mg/kg females = 4980 mg/kg III

870.1100 Acute oral dog 40692304 LD 50 > 974 mg/kg III

870.1200 Acute dermal rabbit 43553201 LD 50 > 2000 mg/kg III

870.1300 Acute inhalation rat 43500801 LC 50 >2.03 mg/L (no
deaths) III

870.2400 Acute eye irritation rabbit 43553203 Corrosive I

870.2500 Acute dermal irritation rabbit 43553202 Non

- irritating IV



### Toxicological PoDs Used for Risk Assessment

For risk assessment purposes, all toxicological values are expressed in terms of boron.

I ncidental oral and short

- and intermediate

- term inhalation exposure s were evaluated based on

the 90

- day and 2

- year dog oral studies (consid ered together to provide the NOAEL and LOAEL) on borax (MRID 406923 08 and 40692310 )

. The subchronic study was conducted using borax, and the chronic study was conducted with boric acid. The findings of the 90

- day, 38

- week and

2

- year dietary studies on bo ric acid were essentially the same as the studies on borax. The selected point of departure of 8.8 mg/kg bw/day (the highest dose tested (HDT) in the chronic study) was based on hematological findings (decreased Hct/Hgb and increased hemosiderin depositio n in the spleen, liver and kidneys) and testicular atrophy observed at the LOAEL of 32

mg /kg bw/day in the 90

- day study. Testicular atrophy was also observed at 40 mg/kg bw/day in a dog 38

- week study (only one dose tested). The observed effects are relev ant to all exposedPage 9 of 60



### populations, which may include young children and females age 13 to 49. The dose is protective of toxicity observed in several oral rat studies ( clinical findings , testicular atrophy) including the subchronic oral rat studies on borax ( NOAEL 41 mg/kg bw/day, HDT) and boric acid (NOAEL/LOAEL 38/125 mg/kg bw/day), as well as the rat chronic toxicity study on boric acid and borax (NOAEL/LOAEL 17/58 mg/kg/day) , and rat reproductive toxicity studies . The selected dose and endpoint are also p rotective of mild renal histopathology seen in pregnant mice (≥43 mg/kg/day) in the developmental toxicity study. The selected dose is protective of developmental toxicity observed in the rat at 13.3 mg/kg bw/day and the rabbit at 43 mg/kg bw/day with dev elopmental NOAELs of 9.6 and 22 mg/kg bw/day, respectively. The inhalation absorption of boric acid/borate salts is assumed to be 100% (i.e., is considered to be equivalent to toxicity via the oral route).

For inhalation exposure, the endpoint and point of departure selection (NOAEL of 8.8 mg/kg/day, dog chronic study) considered a published report on inhalation toxicity in the rat. The requirement for a rat subchronic inhalation toxicity study was waived (K. Rury, TXR No. 0056768, 2/5/2014), based on da ta indicating physical limitations in generating test atmosphere concentrations high enough to elicit toxicity (Wilding et al. , 1959). The published inhalation study did not identify adverse systemic or portal of entry effects in the rat at test concentrations up to 0.47 mg/L boron oxide, which is equivalent to an estimated oral exposure of about 29 mg/kg bw/day boron in the rat

. 2 

### In the absence of observed toxicity in the rat inhalation study, the highest exposure concentration tested (0.47 mg/L) was assumed to be a NOAEL for portal of entry (POE) and systemic toxicity. Human equivalent doses (HEDs) were calculated for compari son to the oral dose of 8.8 mg/kg/day selected for risk assessment and the POE effect

levels . POE HEDs of 3.65 and 1.49 mg/kg bw/day (males) were obtained for occupational and

non

- occupational HEDs, respectively (systemic HEDs were higher). Although lowe r than the oral dose, they are comparable for risk assessment purposes to the selected oral PODs based on the differences in UFs used for inhalation HEDs (30) and oral doses (100). The selected oral

dose (NOAEL) is therefore considered protective of poten tial POE effects from inhalation

exposure.

Additionally, a POD was selected to assess the potential ingestion of recently applied granular formulation products (e.g., in turf) by young children (e.g., 1 < 2 years old). For this scenario, a dose of 350 mg /kg was selected, based on clinical signs (depression, labored/rapid breathing, diarrhea, red crusts on eyes) and mortality observed in oral LD 50 

### studies for boric acid and borax at doses ≥439 mg/kg. The LD 50 

### studies were selected since no single

- dose eff ects relevant to this subpopulation were observed in other guideline toxicology studies. Clinical signs of toxicity in repeated

- dosing studies were not observed by the first or second day of treatment. In several oral

LD 50 

### studies (MRIDs 00056544, 000642 07, 40692303), no effects were observed at doses of 350 mg/kg bw boron equivalents. This endpoint is further supported by the lack of toxicity observed in the rat acute neurotoxicity screening study at the highest dose level of 350 mg/kg boron equivalents

.

2 Calculation: chamber concentration x species specific adjustment factor (respiratory volume and body weight) x exposure duration x 0.311 (factor to convert to boron equivalents for boron oxide) For the rat, 0.47 mg/L x 47 (Fisher rat) x 6 hr exposure du ration x [5 days/7 days per week exposure] x 0.311Page 10 of 60



### A dermal endpoint was not selected, based on in vivo dermal absorption data in humans and published studies in animals indicating that absorption across intact skin is negligible (<1 % ). Estimation of a dermal NOAEL using the NOAELs from the most sensit ive oral studies (NOAEL = 8.8 mg/kg/day, dog and 9.6 mg/kg/day, developmental rat) using a DAF of 1% would yield a dose approaching the li mit dose of 1000 mg/kg bw/day.

HED consider s the potential for concurrent exposure via different routes that produce the same toxicological effects. In the event that the same toxicological effect is produced upon exposure through different routes, HED combine s those exposures . Incidental oral and inhalation exposures are being regulated based on the same effects (hem atological changes, testicular toxicity) observed following oral exposure in the dog.

For all exposure scenarios, uncertainty factors (UFs) of 10x for interspecies (UF A 

### ), 10x for intraspecies (UF H 

### ) variation, and 1x for the Food Quality Protection Act (FQ PA) safety factor (total UF of 100x) were used, thus characterization of risk estimates, in the form of Margins of Exposure (MOEs) are based on a level of 100. The interspecies factor is considered to be

conservative because boric acid/borate salts are ex pected to show similar absorption and tissue distribution among different species, and boric acid is not metabolized. The 10x UF A 

### accounts for variability in renal clearance between species that may affect elimination of boric acid/borate salts, as well as providing additional protection for the close spacing of the rat developmental toxicity NOAEL and LOAEL (9.6 and 13.3 mg/kg bw/da y, respectively). The FQPA factor is 1x

based on an adequate toxicology database

, well

- characterized and clear NOAELs and LOAELs

, dose select ion being protective of potential developmental toxicity , and use of conservative inputs and models for exposure a ssessment

.

There was no evidence of carcinogenicity in cancer studies with mice and rats , although the studies were not conducted according to current guideline standards for carcinogenicity studies

. Boric acid/borate salts are classified as “not likely to be carcinogenic to humans” under the Agency revised (2005) Cancer Guidelines. Genotoxicity studies did not indicate mutagenic or clastogenic potential. Epidemiological data do not indicate any bor on exposure

- related cancers

in humans. Boron is a ubiquitous, naturally occurring element in food and drinking water to which humans are continuously exposed throughout their lifetime, further reducin g concern for pesticide

- related contribution to carcino genicity.

Body Weight

Though the toxicological point of departure (PODs) for adult inhalation assessments were based partly on testicular effects, overall toxicity was seen in both genders, thus, the body weight appropriate for risk assessment is 80 kg ( representing both males and females)

. A body weight of 11 kg was used f

or assessment of incidental oral exposure to children

.

A summary of the toxicological doses and endpoints for occupational and residential human health risk assessment is provide in Table 3.2.Page 11 of 60

3.2 Summary of Toxicological Dose s and Endpoints for Boric Acid/Borate Salts for Use in Occupational

and Residential Human Health Risk Assessments . All d oses expressed as boron equivalents.

Exposure/

Scenario Point of

Departure Uncertainty/

FQPA Safety

Factors Level of

Concern for

Risk

Assessment Study and Toxicological Effects

Incidental

Oral Short

Term (1

- 30 days) and

Intermediate

Term (1

- 6 months) NOAEL= 8.8

mg /kg bw /day (2

- year feeding study

– dog, HDT) UF A = 10x

UF H =10x FQPA SF=1x Residential

LOC for MOE

= 100 Subchronic (90

- day) and chronic (2

- year)

feeding study (borax)

-- dog LOAEL (90

- day study) = 32 mg/kg bw/day, based on hematological effects and testicular atrophy

Dermal (all

durations ) A dermal risk assessment was not performed. Dermal absorption data in humans indicates

negligible absorption (less than 1%) and is consistent with published reports in laboratory animals showing low or no absorption. Estimation of a dermal NOAEL, using a vailable oral NOAELs and a DAF of 1%, would give doses approaching the limit dose (1000 mg/kg bw/day).

Dermal risks are therefore not of concern.

Inhalation

Short

- Term (1

- 30 days)

Intermediate

Term (1

- 6 months) NOAEL= 8.8

mg /kg bw /day (2

- year feeding study

– dog, HDT)

100%

inhalation absorption

assumed. UF A = 10x

UF H =10x FQPA SF=1x Residential and

Occupational

LOC for MOE

= 100 Subchronic (90

- day) and chronic (2

- year)

feeding study (borax)

-- dog LOAEL (90

- day study) = 32 mg/kg

bw /day, based on hematological effects and testicular atrophy

Acute

Incidental

Oral (ingestion of granule formulations) NOAEL = 350

mg/kg UF A = 10x

UF H =10x FQPA SF=1x Residential

LOC for MOE

= 100 Acute LD 50 (boric acid and borax, 3

studies)

– rat
LOAELs ≥439 mg/kg, based on clinical signs of toxicity and mortality

Cancer (oral, dermal, inhalation) Classification: “Not likely to be Carcinogenic to Humans” bas ed on the lack of an increase in

treatment

- related increased tumors in rat and mouse carcinogenicity studies.

Point of Departure = 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

expos ures. 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 populat ion (intraspecies). FQPA SF = FQPA Safety Factor. HDT

– highest dose tested.



### 4 .0 Exposure and Use Profile

There are many pesticide products containing boric acid or one of its sodium salts as the active ingredient . These products include insecticides, acaricides, herbicides, algaecides, fungicides and wood preservatives . A summary of the use profile is provided below.

 Registered f

ormulations include dusts, granules /pellets/baits , wettable or water

- soluble powder s/dusts , liquid concentra te s
, and gels/ paste s

.

 U se sites and targets include :Page 12 of 60 

### o A gricultural food/feed crops;

o Residential areas (homes, schools, nursing homes, hospitals, etc.):

 Indoor (pet quarters, floors/carpets, attics; cracks/crevices, around appliances, bedding/mattresses);

 Ou tdoor (lawns, parks, golf courses, building perimeters, patios, driveways, trash areas, wood piles, gardens);

o Pre

- construction wood material;

o Wooden structures (utility poles, railroad ties, etc.);

o Structural Building/House Components (wall/cabinet voids, soffits, attic space, crawl spaces)

o Swimming pools;

o Food handling/storage/processing sites;

o Poultry houses;

o Industrial areas;

o Sewers/sewage systems;

o Tree stumps;

o Vehicles (ships, buses, etc.);

o Ant mounds.

 Depending on the use pattern, the percentage of act ive ingredient ranges from less than 1% (e.g., liquid concentrate for use on crops) to 100% (e.g., indoor insecticide dusts)

.

 Application types can be broadcast as well as spot or crack

- and

- crevice type treatments.

 Applications are made via hand dispersal, with handheld equipment (e.g., rotary spreaders, handwand sprayers), and with vehicles (e.g., tractor

- drawn spreaders, airblast sprayers). Chemigation and aerial applications are prohibited.

 Application rates vary depending on the use site/target and formulation. For example, i n terms of boron equivalents, spray application to crops has a relatively low rate of 0.0018 lb boron/acre, while applications of dusts to poultry houses has a relative ly high rate of

448 lb boron/acre.

 The minimum retreatment interval for crop uses is 7 days; non

- crop uses are applied on

an as

- needed basis.

 Work attire and/or personal protective equipment (PPE) is not specified on many labels while on others, such as the crop use product (EPA Reg. No. 72662

- 3) the label requires protective eyewear/goggles, long

- sleeve shirt, pants, waterproof gloves, shoes and socks.

Some labels require use of respiratory protection.

 For many p roducts, such as those not subject to the EPA’s Worker Protection Standard, a restricted entry interval (REI) does not apply. Where applicable, the REI varies from 4

hours on some labels to 48 hours on other labels

.

As there are numerous products with bo ric acid/sodium salts, Table 4.1 below outlines representative registered products on which the exposure and risk assessment is based. Application rates are presented in terms of boron equivalents for purposes of comparison with toxicological studies

– co nversions from boric acid or a specific sodium salt are performed using the molecular weight composition of boron in the active ingredient.Page 13 of 60

Table 4.1. Summary of Registered Use Directions for Boric Acid and its Sodium Salts

Application Type/Equip/etc. F ormulation

[Representative EPA Reg. No.] Maximum Application Rate 1 PPE/Work Attire, REI,

Retreatment

Grass/Turf (Homes, Parks, Golf courses) , Ant mounds, Building Perimeters

Broadcast application

via:

 Tractor

- drawn spreader

 Hand dispersal

 Belly grinder

 Cup/Spoon

 Push

- type rotary spreader Granule (insecticide)

EPA Reg. No. 19713

- 522 (Drexel Borxel)

5% boric acid Product rate 4 lb product/1000 ft 2

 Retreatment not specified

 PPE: eyewear/goggles, long sleeve shirt, long pants, waterproof gloves,

shoes/socks

 REI not specified Active ingredient rate 0.2 lb boric acid/1000 ft 2

9 lb boric acid/acre

Boron equivalent rate 1.5 lb boron/acre

0.035 lb boron/1000 ft 2

Golf Course Turf and Agricultural Food/Feed Crops (alfalfa, cane berries, bush berries, coffee, cacao, pome fruit, stone fruit, citrus, herbs, tree nuts, peanuts, strawberry, tobacco, Brassica leafy vegetables, bulb vegetables, corn, cucurbit, fruiting veg etables, leafy vegetables, except Brassica, legumes, root and tuber vegetables, soybean, cotton, herbs, avocado, kava,

banana, guava, papaya, pineapple, watermelon and grasses) and Golf Course Turf

Broadcast application

via:

 Groundboom

sprayer

 Airblast sprayer

 Chemigation

and aerial application is prohibited Liquid concentrate (insecticide)

EPA Reg. No. 72662

- 3 (Prev

- Am Ultra)

0.99% sodium tetraborohydrate decahydrate (STD) Product rate 100 fl oz/100 gal soln

25 gal soln/acre

 Minimum retreatment is

7 days.

 PPE: eyewear/goggles, long sleeve shirt, long pants, waterproof gloves,

shoes/socks

 REI: 12 hours Active ingredient rate 0.00065 lb STD/gal soln

(product rate * 8.34 lb/gal soln * 0.99% ai)

0.016 lb STD/acre (0.00065 lb STD/gal soln * 25 gal soln/acre)

Boron equivalent rate 0.0018 lb boron/acre

Home gardens, lawns, greenhouses, ornamentals, shrubs

Broadcast application via hand sprayers (e.g., hose

- end sprayers, handwand sprayers) Liquid concentrate

(insecticide)

EPA Reg. No. 72662

- 5 ( Prev

- Gard)

0.99% sodium tetraborohydrate decahydrate (STD) Product rate 1 fl oz. product/gal soln.

1 gal soln/1000 ft 2

 Spray every 7

- 10 days or as frequently as every 4 days

 PPE: eyewear/goggles, long sleeve shirt, long pants, waterproof gloves,

shoes/s ocks

 REI: 12 hours Active ingredient rate 0.00065 lb STD/gal

soln/1000 ft 2 (product rate * 8.34 lb/gal soln * 0.99% ai)

0.03 lb STD/acre

Boron equivalent rate 0.000073 lb boron/gal

soln/1000 ft 2

0.003 lb boron/acre

Tree Stumps

Application via

shaker can or hand

sprayers Dust/powder

(fungicide)

EPA Reg. No. 2935

- 501 (Sporax) Product rate 1 lb/50 ft 2 stump surface (equiv. 250 six inch stumps)

1 lb/gal soln/50 ft 2 stump surface (assume 1 gallon

wat er dilution )  Spray every 7

- 10 days or as frequently as every 4 days

 PPE: eyewear/goggles, long sleeve shirt, long pants (or coveralls),Page 14 of 60

Table 4.1. Summary of Registered Use Directions for Boric Acid and its Sodium Salts

Application Type/Equip/etc. F ormulation

[Representative EPA Reg. No.] Maximum Application Rate 1 PPE/Work Attire, REI,

Retreatment

100% sodium tetraborohydrate decahydrate (STD) Active ingredient rate 1 lb STD/gal soln/50 ft 2

(product rate * 100% ai) waterproof gloves,

shoes/socks

 REI: 48 hours

Boron equivalent rate 0. 11 lb boron/gal soln/50

ft 2

0.0023 lb boron/gal

soln/ft 2

Indoor Crack

- and

- crevice (Residential, Commercial, Recreational ) and Sewers

Application via shaker can, bulb

dusters , power dusters Dust (insecticide)

EPA Reg. No. 56

- 73 (Eaton’s Answer)

99% boric acid Product rate 20 oz container

12 oz/190 ft 2

 No retreatment, PPE, or REI specified Active ingredient rate 19.8 oz boric acid/20 oz

container

11.9 oz boric acid/190 ft 2

Boron equivalent rate 0.22 lb boron/20 oz

container

0.00068 lb boron/ft 2

30 lb boron/ acre

Application via hand dispersal Granule (insecticide)

EPA Reg. No. 64405

- 2 (Redzone Bait)

5% boric acid Product rate 2 lb/1000 ft 2

 PPE: eyewear/goggles, long sleeve shirt, long

pants, waterproof gloves,

shoes/socks

 REI: 4 hours

 No retreatment specified Active ingredient rate 0.1 lb boric acid/1000 ft 2

Boron equivalent rate 0.017 lb boron/1000 ft 2

0.76 lb boron/acre

Structural Building/House Components (wall/cabinet voids, soffits, attic space, crawl spaces)

Application via bulb and power dusters Dust/Wettable Powder

(insecticide/fungicide)

EPA Reg. No. 64405

- 8 (Nibor Borate)

98% disodium octaborate tetrahydrate (DOT) Product rate 0.5 oz/ft 2

1.5 lb/gal water

 PPE: eyewear/goggles, long sleeve shirt, long pants, waterproof gloves, shoes/socks, respirator in confined spaces

 REI: 48 hours

 No retreatment specified Active ingredient rate 0.49 oz DOT/ft 2

1.47 lb DOT/ gal soln

Boron equivalent rate 0.21 lb boron/lb product

0.1 oz boron/ft 2

0.0065 lb boron/ft 2

0. 31 lb boron/ gal soln

Application via hand sprayers (backpack, handgun, airless

sprayers, brush/rollers) Liquid concentrate

(insecticide/fungicide)

EPA Reg. No. 83465

- 1 (GB

- 40) Product rate 1 gallon product per 1 gallon water = 1 gal prod/2 gal soln (1 gallon product = 11.5

lbs)  PPE: eyewear/goggles,

long sleeve shirt, long pants, chemical resistant gloves, shoes/socks, respirator in confinedPage 15 of 60

Table 4.1. Summary of Registered Use Directions for Boric Acid and its Sodium Salts

Application Type/Equip/etc. F ormulation

[Representative EPA Reg. No.] Maximum Application Rate 1 PPE/Work Attire, REI,

Retreatment

40% disodium

octaborate tetrahydrate (DOT) Active

ingredient rate 2.3 lb DOT/gal soln

(product rate * 40% ai) spaces

 REI: 48 h ours

 No retreatment specified

Boron equivalent rate 0.32 lb boron/gal soln

Poultry House, Soil/Manure, Garbage/Municipal Dumps

Application via bulb and power dusters

and via hand sprayers Dust/Wettable Powder (insecticide)

EPA Reg. No. 1624

- 11 (Polybor 3)

98% disodium octaborate tetrahydrate (DOT) Product rate 5 lb/100 ft 2

2 lb/gal water

3 gal soln/100 ft 2  PPE: eyewear/goggles, long sleeve shirt, long pants, chemical resistant gloves, shoes/socks, respirator under certain

conditions

 REI not specified

 No retreatment specified Active ingredient rate 4 .9 lb DOT/100 ft 2

0.65 lb DOT/gal soln

Boron equivalent rate 1 lb boron/100 ft 2

0.14 lb boron/gal soln

448 lb boron/acre
Indoor Residential Carpets, Rugs, Upholstery

Application via hand

sprayers RTU Solution

(insecticide)

EPA Reg. No. 64405

- 6 (RTU Flea Spray)

8.5% disodium octaborate tetrahydrate (DOT) Product rate 1 gal/750 ft 2

 No retreatment, PPE, or REI specified Active ingredient rate 0.71 lb DOT/gal soln

(1 gal prod * 8.34 lb/gal * 8.5% ai)

0.00095 lb DOT/ft 2

Boron equivalent rate 0.15 lb boron/gal soln

0.0002 lb boron/ft 2

Application via hand

sprayers D ust/

Wettable powder (insecticide)

EPA Reg. No. 67419

- 1 (Ecology Works)

98% disodium octaborate tetrahydrate (DOT) Product rate 1 cup/0.5 gal water

1 cup/100 ft 2

 Reapply every 8 weeks

 No PPE or REI specified Active ingredient rate 0.86 lb DOT/gal soln

(1 cup * 200 grams/cup * 1 lb/454 grams * 98% ai)

0.00 43 lb DOT/ft 2

Boron equivalent rate 0.1 8 lb boron/gal soln

0 .0009 lb boron/ft 2

Bed Bug Treatments (Mattresses, Bed Frames, Floorboards, Baseboards, Carpets, Walls)
Application via hand

sprayers RTU Solution

(insecticide) Product rate 5 ounces/ft 2  No retreatment, PPE, or REI specifiedPage 16 of 60

Table 4.1. Summary of Registered Use Directions for Boric Acid and its Sodium Salts

Application Type/Equip/etc. F ormulation

[Representative EPA Reg. No.] Maximum Application Rate 1 PPE/Work Attire, REI,

Retreatment

EPA Reg. No. 64405

- 6 (RTU Flea Spray)

8.5% disodium octaborate tetrahydrate (DOT) Active

ingredient rate 0.71 lb DOT/gal soln

(1 gal prod * 8.34 lb/gal

* 8.5% ai)

0.028 lb DOT/ft 2

Boron equivalent rate 0.15 lb boron/gal soln

0.0058 lb boron/ft 2

Industrial Areas, Lots, Fence Lines, Runways, Underneath Asphalt, Wood Decks, Bleachers Broadcast application

via:

 Tractor

- drawn spreader

 Hand dispersal

 Belly grinder

 Cup/Spoon

 Push

- type rotary spreader

 Backpack Granule (herbicide)

EPA Reg. No. 33560

- 46 (Barespot)

49% sodium metaborate Product rate 3 lb product/100 ft 2

 PPE: eyewear/goggles, coveralls over long sleeve shirt and long pants, chemical resistant gloves, shoes/socks

 REI not specified

 No retreatment specified Active ingredient rate 1.5 lb sodium

metaborate/100 ft 2

653 lb sodium

metaborate/acre

Boron equivalent rate 105 lb boron/acre

1 Conversions to boron are performed based on the compound’s molecular weight percentage:

Boric acid: 17.48% boron (multiply ai rate by 0.1748) Sodium tetraborate decahydrate: 11.34% boron (multiply ai rate by 0.1134) Sodium tetraborate pentahydrate: 14.85% boron (multiply ai rate by 0.1485)

Sodium te traborate anhydrous: 21.5% boron (multiply ai rate by 0.215) Disodium octaborate tetrahydrate: 20.96% boron (multiply ai rate by 0.2096) Disodium octaborate anhydrous: 25.83% boron (multiply ai rate by 0.2583) Sodium metaborate: 16.41% boron (multiply ai rate by 0.1641)



### Considering the use pattern, dermal and inhalation exposures are anticipated for both occupational and residential handlers (mixer/loaders, applicators, etc.). In addition, post

application exposures are also possible, including dermal exposures to re

- entry field workers, and dermal and incidental oral exposures to children playing on treated grass as well as via spray

drift res ulting from crop applications.

5 .0 Residential Exposure and Risk Estimates

There are numerous conventi onal residential use s of boric acid or its sodium salts as active ingredients, from insecticide and fungicide dusts and sprays to granular herbicides. Additionally, there are antimicrobial uses in swimming pools and as wood preservatives, however, those a re addressed in a separate assessment.

Given these uses, both residential handler and post

- application exposures are anticipated. Addressed below are inhalation exposures for consumers mixing/loading and applying boric acid products as well as post

- appli cation inhalation and incidental oral exposures resulting from areas previously treated with boric acid products. As described previously, dermal toxicity was not identified, thus dermal risks are not quantitatively addressed

.Page 17 of 60



### Note also, as boric acid and its sodium salts are classified as “Not Likely to be Carcinogenic to Humans” only non

- cancer risks are quantified

.

5.1 Residential Handler Exposure/Risk Estimates

HED uses the term “handlers” to describe those individuals who are involved in the pest icide 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.

The quantitative exposure/risk assessment developed for residential handlers is based on the following scenarios

.

 Indoor area treatments (carpets, floors, crack

- and

- crevice treatments, attics, wall voids, crawl spaces, etc.)

o Loading/applying dust/powder formulations with :

 Hand pressure dusters (e.g., bulb dusters, plunger dusters, hand crank dusters)

 Power dusters/blo wers

 Shaker cans

o Applying granules/baits via hand dispersal

o Mixing/loading/applying wettable dusts/powder formulations with a manually pressurized handwand sprayer

o Mixing/loading/applying liquid concentrate formulations with a manually pressurized handwand sprayer

o Applying bait gels/pastes

 Outdoor area treatments (lawns, gardens, shrubs/bushes, and fruit/nut trees)

o Loading/applying granule formulations with push

- type rotary spreaders

o Applying granule formulations via hand dispersal or with spoons or cups

o Mi xing/loading/applying liquid concentrate formulations with

 M anually pressurized handwand sprayer s

 Hose

- end sprayers

 Backpack sprayers

 Sprinkler cans

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 assumption and factor is detailed below.

Application Rate:

V arious application rates are provided in Table 4.1 and are applied for specific scenarios and application methods.Page 18 of 60



### 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



### . Where default values are not provided in the SOPs, the assessment considers label langu age regarding the extent of the treatment as well as professional judgment considering house size and application capabilities of consumers.

Exposure Duration :

Residential handler exposure is generally expected to be short

- term in duration , though given

many boric acid/sodium salt labels don’t specify treatment frequency and the use of boric acid and its sodium salts is likely on an as

- needed basis (particularly its residential insecticide use), there is potential for intermediate

- term handler exposure as well

. However, the toxicological endpoint selected for the short

- term assessment is protective of both short

- and intermediate

- term
durations

.

Residential Handler Non

- Cancer Exposure and Risk Estimate Equations

The algorithms used to estimate exposure and dose for residential handlers can be found in the

2012 Residential SOPs 4 

### and Appendix A.

Combining Exposures/Risk Estimates

Residential handler dermal and inhalation exposures were not combined because dermal toxicity

was not identified in the boric acid toxicity database

.

Summary of Residential Handler Non

- Cancer Exposure and Risk Estimates

I nhalation exposures and risks were calculated for residential handlers assuming no respiratory protection ; n o estimates of inhalation risk were of concern.

Table 5.1.1 presents detailed exposure and risk calculations.

3 Available: http://www.epa.gov/pesticides/science/residential

- exposure

- sop.html

4 Available: http://www.epa.gov/pesticides/science/residential

- exposure

- sop.htmlPage 19 of 60

Table 5.1

. 1. Summary of Residential Handler Risk Estimates for Boric Acid and its Sodium Salts

Use Site Category Exposure Scenario App Rate 1 Amount

Handled/ Area

Treated 2 Unit Exposure

( m g/lb ai) 3 Dose (mg/kg/day) 4 Inhalation MOE 5
(LOC = 10 0) I nhalation (no respirator) Inhalation

(no respirator)

Indoor

treatments Mixing / loading

/ applying with a manually pressurized

handwand L iquids 0.15 lb ai/ gallon

dilute solution 0.5 gallons dilute

solution 1.1 0.001 8500

Wettable dusts/powders 0. 31 lb ai/ gallon

dilute solution 1.1 0.0021 4100

Applying granules/baits via hand

dispersal 0.000017 lb ai/ft 2 1000 ft 2 0.38 0.000081 110000

Loading /

a pplying dusts/powders Shaker can 0.22 lb ai/20 oz

container One 20 oz

container 18 0.05 180

Power

duster/blower 0.21 lb ai/lb dust 1 lb dust 18 0.024 370

Bulb Duster 0.21 lb ai /lb dust 0.25 lb dust 1.7 0.0011 7900

Plunger Duster 0.21 lb ai/lb dust 0.5 lb dust 1.7 0.0022 3900

Applying bait gels/pastes No exposure/risks expected from gel/paste formulations

.

Outdoor

treatments (lawns, gardens, and trees) Loading /

applying granules Rotary spreader 1.52 lb ai/acre 0.5 acres 0.0026 0.000025 360000

Belly grinder 0.034 lb ai/1000

ft 2 1200 ft 2 0.039 0.00002 430000

Spoon 0.034 lb ai/1000

ft 2 1200 ft 2 0.013 0.00054 1300000Page 20 of 60

Table 5.1

. 1. Summary of Residential Handler Risk Estimates for Boric Acid and its Sodium Salts

Use Site Category Exposure Scenario App Rate 1 Amount

Handled/ Area

Treated 2 Unit Exposure

( m g/lb ai) 3 Dose (mg/kg/day) 4 Inhalation MOE 5
(LOC = 10 0) I nhalation (no respirator) Inhalation

(no respirator)

C up 0.034 lb ai/1000

ft 2 1200 ft 2 0.087 0.000046 190000

Applying granules via hand dispersal 0.034 lb ai/1000

ft 2 1200 ft 2 0.38 0.0002 44000

Mixing / loading / applying liquids Manually

pressurized

handwand 0.000073 lb

ai/gallon dilute

solution 5 gallons dilute

solution 0.018 8.2E

- 08 110000000

Hose

- end

sprayer 0.003 lb ai/acre 0.5 acres 0.022 4.1E

- 07 21000000

Backpack

sprayer 0.000073 lb

ai/gallon dilute

solution 5 gallons dilute

solution 0.14 6.4E

- 07 14000000

Sprinkler can 0.000073 lb

ai/1000 ft 2 1000 ft 2 0.022 2.0E

- 08 440000000

1 Based on registered l abel s outlined in Table 4.1. All rates expressed in terms of boron

. 2 Based on HED’s 2012 Residential SOPs ( http://www.epa.gov/pesticides/science/residential

- exposure

- sop.html ).

3 Inhalation Dose = Inhalation Unit Exposure (mg/lb ai) × Application Rate (lb ai/acre or gal) × Area Treated or Amount Handled (A /day or gallons/day) ÷ BW (kg). Expressed

in terms of b oron. 4 Inhalation MOE = Inhalation POD (mg/kg/day) ÷ Inhalation Dose (mg/kg/day).Page 21 of 60



### 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 boric acid or a borate sodium salt

. As no dermal toxicity was identified, t he quantitative exposure/risk assessment for residential post

application exposures is based on the following scenarios:

 Inhalation exposure for adults and children (1 < 2 years old) following indoor treatments (carpets, floors, crack

- and

- crevice, bedding/mattresses)

 Incidental oral children’s (1< 2 years old) exposure from contact with treated:

o Turf/lawns

o Carpets and floors

The lifestages selected for each post

- application scenario are based on an analysis provided as an Appendix in the 2012 Residential SOPs 5



### . While not the only lifestage potentially exposed for these post

- application scenarios, the lifestage that is inclu ded in the quantitative assessment is health protective for the exposures and risk estimates for any other potentially exposed lifestage.

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

SOP s and Appendix A.

Application Rate:

V arious application rates are provided in Table 4.1 and are applied for specif ic scenarios and application methods.

A pplication rates were utilized in conjunction with molecular weights (in grams/mole) and vapor pressures (in mmHg) shown in the table below to estimate air concentrations via volatilization of liquid indoor sprays.

Compound Molecular weight (g/mol) Vapor pressure (mmHg)

Boric acid 61.83 < 10

- 4

Sodium tetraborate decahydrate (STD) 381.43

< 10

- 6 Sodium tetraborate pentahydrate 291.35

Sodium tetraborate anhydrous 201.22

Disodium octaborate tetrahydrate 412.31

Disodium octaborate anhydrous 340.31

Sodium metaborate 65.82

5 Available: http://www.epa.gov/pesticides/scie nce/residential

- exposure

- sop.htmlPage 22 of 60



### Exposure Duration :

Post

- application exposures are generally considered short

- term in nature. However, the toxicity study from which the inhalation and incidental oral toxicological endpoint s were selected to
assess post

- application exposures is of sufficient duration to assess both short

- and intermediate

term exposure durations

.

Residue Transferability

In accordance with 40CFR158, turf transferable residue ( TTR ), dislodgeable foliar residue (DFR), and indoor surface residue data are required for all occupational or residential uses that could result in post

- application exposure s

. In the absence of chemical

- specific residue data,

EPA uses default values. Since no systemic dermal toxicity was identified and the estimated

residential turf incidental oral post

- application exposure u sing default TTR values for boric

acid/sodium salts is minimal in comparison to the level of concern (i.e., the calculated MOE is

greater than 10 times higher than the level of concern, MOEs ≥ 10,000 compared to the LOC of 100), TTR data are not needed

. For this scenario , it is unlikely that chemical

- specific residue data would be needed to further refine exposure assessments or would add a ppreciably to

our general understanding of the availability of turf transferable residues.

For indoor surface residues, d uring and after the boric acid and its sodium salts Tolerance Reregistration Eligibility Decision (TRED) process in 1995/1996, registr ants submitted studies aimed at informing and refining estimates for post

- application indoor exposures , in particular residue transferability

. All residue transferability estimates were derived using the “ California

roller metho d” 6 

### . As described in the 2 012 Residential SOPs, exposure contact factors (i.e., transfer coefficients) used to estimat e indoor post

- application dermal and incidental exposures

are derived from datasets that utilized the same California roller method and a modified version

of the California roller method. Thus the submitted studies are consistent with standard procedures for estimating indoor post

- application exposures, and thus satisfy the 40CFR data requirements.

Across all the studies, which in cluded varying types and conditions of carpets, transferability (as a percentage of the application rate) of boric acid/sodium salts ranged from 0.03% to 0.95%. To
represent typical conditions for short

- /intermediate

- term post

- application risk assessments

, transferability of 0.1% will be used for dust treatments to carpets ( selected from MRID

47579901 ) and 0.4% for dust treatments to hard floors and liquid treatments to carpets or hard

surfaces ( selected from MRID 47579902, the only result available for th ese conditions)

. The

s ubmitted s tudies are listed and briefly summarized below.

6 Ross, J.H., Fong, H.R., Thongsinthusak, T., Margetich, S. and Krieger, R. 1991. Measuring Potential Dermal Transfer of Surface Pesticide Residue Generated from Indoor Fogger Use: Using the CDFA Roller Method.

Interim Report II. Chemosphere, Vol. 22. Nos.9

- 10:975

- 984Page 23 of 60 Title EPA

MRID Author Applicability for Pesticide Exposure

Assessment

Contact Transfer of Eco

- Fresh Borate

Treated Surfaces to Evaluate Human Exposure Potential 47579902 Robert Krieger (Univ. of California, Riverside) Residue transferability

from dust

- treated carpets

and solution

- treated hard

floors

Contact Transfer of Flea

- Be

- Gone Insecticide from Carpets to Evaluate Human Exposure Potential 475 7 990 1 Robert Krieger (Univ . of California, Riverside) Residue transferability

from dust

- treated carpets

Dosimetry Study for Rx for Fleas Plus: A Toxicology Review of Boric Acid and its Salt, Exposure Assessment, and

Risk Characterization 46971101 Robert Yarmuth, Environmental

Tox icology International Residue transferability

from dust

- treated carpets

Human Disodium Octaborate Tetrahydrate Exposure Following Carpet Flea Treatments Is Not Associated with Significant Dermal

Absorption 46852202 Robert Krieger and Travis Dinoff (Univ. of California, Riverside) and James Peterson (Pacific Toxicology Lab). J Expo Anal Env Epi. Vol 6, No.

3, 1996. Residue transferability and characterizing dermal

exposure (biomonitoring)



### EPA MRID 47579902

– Contact Transfer of Eco

- Fresh Borate T reated Surfaces to Evaluate Human Exposure Potential

This stu dy was conducted in 1996 by Robert Krieger of the University of California, Riverside Dept. of Entomology and submitted to the EPA in 2007 by U.S. Borax Inc. following information requests in th e EPA TRED for boric acid/sodium salts. The study used the “California roller” technique to measure boric acid transferability from treated carpets and linoleum floors. No human subjects were involved in the conduct of the study.

The test material (EPA Reg. No. 66480

- 1, Eco

- Fresh , 64% boric acid

– a product since canceled) , a dust, was applied to carpets as a dust at a rate of 3 lb of product per 100 ft 2


### (equivalent to 9.3 mg boric acid/cm 2 

### ) and to linoleum floors as a solution at a rate of 197 grams product in a gallon of water to 100 ft 2 

### of floor (equivalent to 1.3 mg boric acid/cm 2 

### ).

Transferable surface residue was measured using the “California roller” technique, a method that employs a short

- handled 25 pound roller, rolled 20 times over a 3,932 cm 2 

### cotton percale sheet covered by polyethylene, according to the protocol from Ross, 1991 7 

### . Samples were taken

before and after treatment ; before

- treatment samples showed negligible background boron levels

. Fortification of the cotton percal e sampler w as done at 3 levels, 0.505 mg, 1.01 mg, and 2.02 mg, with results averaging 129%, 114%, and 95% at each of those levels, respectively.

Transferability results, expressed in terms of a percentage of the application rate are shown in the

table below. Tho ugh conducted without prior EPA consideration of the study protocol, the results are reasonable to consider for the purposes of boric acid/sodium salts risk assessment.

7 Ross, J.H., Fong, H.R., Thongsinthusak, T., Margetich, S. and Krieger, R. 1991. Measuring Potential Dermal Transfer of Surface Pesticide Residue Generated from Indoor Fogger Use: Using the CDFA Roller Method. Interim Report II. Chemosphere, Vol. 22. Nos.9

- 10:975

- 984.Page 24 of 60 Transferability Results from MRID 47579902

Application/Surface Application Rate

(mg boric acid/cm 2 ) Average Transferable

Residue 1

, 2 ,3

(mg boric acid/cm 2 ) Transfer Efficiency

(% of app. rate) 4

Dust to c arpet (“open pile/little wear”) 9.3 0.0008 0.009

0.03 Dust to c arpet (“short pile/more wear”) 0.005 0.05

Solution to l inoleum 1.3 0.005 0.4

1 No adjustment for f

ortification recover ies (results acceptable).

2 Measurements per 3,932 cm 2 of sampler.

3 No adjustment for background boron levels which were insignificant.

4 Calculated as measurement divided by rate.



### EPA MRID 4757990 1

– Contact Transfer of Flea

- Be

- Gone Insecticide from Carpets to Evaluate Human Exposure Potential

This study was conducted in 199 7 by Robert Krieger of the University of California, Riverside Dept. of Entomology and submitted to the EPA in 2007 by U.S. Bo rax Inc. following information requests in the EPA TRED for boric acid/sodium salts. The study used the “California roller” technique to measure boric acid transferability from treated carpets. No human subjects were involved in the conduct of the study.

The test material (EPA Reg. No. 6 9115

- 1, Flea

- Be

- Gone , 6 5 % boric acid

– a product since canceled), a dust, was applied to carpets as a dust at a rate of 1 lb of product per 5 00 ft 2


### (equivalent to 0.63 mg boric acid/cm 2 

### ).

Transferable surface residue was measured using the “California roller” technique, a method that employs a short

- handled 25 pound roller, rolled 20 times over a 3,932 cm 2 

### cotton percale sheet covered by polyethylene, according to the protocol from Ross, 1991. Samples were taken before

a nd after treatment ; before

- treatment samples showed background boron levels ranging from 0.027 to 0.111 ug boron/cm 2 

### . Fortification of the cotton percale sampler was done at 3 levels, 0.5 mg, 1 mg, and 2 mg, with results averaging 75 %, 71 %, and 69 % at eac h of those levels, respectively.

Transferability results, expressed in terms of a percentage of the application rate are shown in the

table below. Though conducted without prior EPA consideration of the study protocol, the results are reasonable to consider for the purposes of boric acid/sodium salts risk assessment.

Transferability Results from MRID 47579901

Carpet

Section Average Transferable Re sidue

(ug boric acid/cm 2 ) 1,2 Study Application Rate (ug boric acid/cm 2 ) 4 Transfer Efficiency (%) 5 Pre

- treatment Post

- treatment Corrected 3

A 0.0337 0.516 0.482

630 0.0766

E 0.0337 0.661 0.627 0.0996

F 0.027 0.476 0.449 0.0713Page 25 of 60

G 0.111 0.361 0.250 0.0397

Overall

average 0.05135 0.5035 0.45215 0.0718

1 Adjusted for 71.8% recovery (overall average)

2 Reflect boric acid measurements normalized to 3932 cm 2

3 Corrected = post

- treatment minus pre

- treatment

4 Rate calculated from a 65% boric acid product applied at a rate of 1 pound per 500 ft 2

.

5 Calculated as measurement divided by rate.



### EPA MRID 46971101 Dosimetry Study for Rx for Fleas Plus: A Toxicology Review of Boric Acid and its Salt, Exposure Assessment, and Risk Characterization

This study was conducted in 1994 by Environmental Toxicology International and submitted to the EPA in 2005 by the sponsors Rx for Fleas and InCide Technologies following information requests in the EPA TRED for boric acid/sodium salts. In addition to an assessment of boric acid/sodium salts toxicology and risk, the study characterized the potential for exposure via

measurement of residue transfer following application of a boric acid dust product to carpets. No human subjects were involved in the conduct of the study.

The test material ( EPA Reg. No. 59111

- 1, Rx For Fleas Plus , 6 4 % boric acid), a dust, was applied to carpets as a dust at rates of 9.1 grams of product per ft 2 

### (equivalent to 0. 013 lb b oric

acid/ ft 2 

### or 1066 ug boron/cm 2 

### ) and 3.8 grams of pro duct per ft 2 

### (equivalent to 0.0054 lb boric

acid/ft 2 

### or 445 ug boron/cm 2 

### ).

Transferable surface residue was measured using the “California roller” technique, a method that employs a short

- handled 25 pound roller, rolled 20 times over a 3,932 cm 2 

### cotton pe rcale sheet covered by polyethylene, according to the protocol from Ross, 199 1 . Samples were taken before and after treatment; before

- treatment samples showed negligible background boron levels. Fortification of the cotton percale sampler results averag ed approximately 90%

.

Transferability results, expressed in terms of a percentage of the application rate are shown in the

table below. Though conducted without prior EPA consideration of the study protocol, the

results are reasonable to consider for t he purposes of boric acid/sodium salts risk assessment.

Transferability Results from MRID 47579901

Application Rate 1

Carpet/Condition Residue

Measurement
(ug boron/cm 2 ) 2 Mean Transfer

Efficiency (%) 3 g prod/ft 2 ug boron/cm 2

3.8 445 Carpet (standard condition) 0.51 0.11

Carpet (extreme condition) 4.24 0.95

9.1 1066 Carpet (standard condition) 0.95 0.09

Carpet (extreme condition) 3.43 0.32

1 Product is 64% boric acid . Boric acid is 17.48% boron.

2 Reflect boron measurements normalized to 17 in x 17 in sampler (1864 cm 2 )

3 Calculated as measurement divided by rate.Page 26 of 60



### EPA MRID 46852202 Human Disodium Octaborate Tetrahydrate Exposure Following Carpet Flea Treatments Is Not Associated with Significant D ermal Absorption

This is a published article in the Journal of Exposure Analysis and Environmental Epidemiology

– Krieger, et al. 1996 . The study obtained biomonitoring (urine) samples from volunteers performing Jazzercise routines on carpets treated with a dust product containing disodium octaborate tetrahydrate (DOT). Residue transferability was also measured using the same

California roller method previously described for the other studies.

Unlike the other available studies described above, the r aw data wa s not presented for discrete analysis, thus a determination of the transferability was not pursued

.

Residential Post

- application Non

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

- application exposure and dos e can be found in

the 2012 Residential SOPs 8 

### and Appendix A.

Combining Exposure and Risk Estimates

Based on the available toxicological information for boric acid/borate salts, dermal exposures are

not anticipated to result in adverse systemic effect s due to minimal absorption, and therefore not quantitatively assessed

. Since i ncidental oral and inhalation exposures are b ased on the same

toxico lo gical effects they are combined

.

Summary of Residential Post

- application Non

- Cancer Exposure and Risk Es timates

Risk estimates of concern were identified for hand

- to

- mouth exposures for children following indoor bedbug treatments (MOE = 8 ) and indoor carpet spray treatments (MOE = 51)

. These

route s are also combined with inhalation exposure, but as inhalat ion exposure is much lower in comparison to the hand

- to

- mouth exposure, the risk estimate s are unchanged.

The application rates are relatively high for pesticide applications, particularly the bed bug

treatment application rate (based on EPA Reg. No. 64 405

- 6 ) at approximately 6 pounds of boron

per 1000 square foot of carpet. Crack

- and

- crevice treatments

– assumed to result in substantially

less surface residue than broadcast treatments

– did not result in risk estimates of concern for

incidental oral ex posure scenarios.

Table 5.2.1 below outlines in more detail the exposure scenarios and exposure and risk

calculations. Combined exposure scenarios are shown as well for children: incidental oral scenarios are combined with post

- application inhalation exposure resulting from general indoor

spray treatments

.

8 http://www.epa.gov/pesticides/science/residential

- exposure

- sop.htmlPage 27 of 60

Table 5.2.1. Residential Post

- application Exposure and R isk Estimates for Boric Acid/Sodium Salts

Lifestage Post

- application Exposure Scenario Application Rate 1 Dose (mg/kg/day) 2 MOEs 3

Use Site Route of Exposure Route

specific Combined 5

Adult Bed Bug

treatments Carpets Liquids Inhalation 0.71 lb DOT/gallon dilute

solution
(0.0058 lb boron/ft 2 ) 0.00051 17000

--

Child Bed Bug

treatments Carpets Liquids Inhalation 0.71 lb DOT/gallon dilute

solution
(0.0058 lb boron/ft 2 ) 0.0022 4000

--

Carpets 4 Liquids Hand

- to

- Mouth 0.0058 lb boron/ft 2 1.12 8 8

Object

- to

- Mouth 0.0058 lb boron/ft 2 0.037 240 220

General

Indoor

treatments Carpets 4 Liquids Hand

- to

- Mouth 0.0009 lb boron/ft 2 0.17 51 51

Dusts Hand

- to

- Mouth 0.00068 lb boron/ft 2 0.033 270

-- Liquids Object

- to

- Mouth 0.0009 lb boron/ft 2 0.023 380 350

Dusts Object

- to

- Mouth 0.00068 lb boron/ft 2 0.004 2000

--

Hard floors 4 Liquids Hand

- to

- Mouth 0.0009 lb boron/ft 2 0.043 200 190

Dusts Hand

- to

- Mouth 0.00068 lb boron/ft 2 0.033 270

-- Liquids Object

- to

- Mouth 0.0009 lb boron/ft 2 0.012 760 620

Dusts Object

- to

- Mouth 0.00068 lb boron/ft 2 0.009 1000

--

Crack

- and

crevice Carpets 4 Liquids Hand

- to

- Mouth 0.0009 lb boron/ft 2 0.017 510 460

Dusts Hand

- to

- Mouth 0.00068 lb boron/ft 2 0.0033 2700

-- Liquids Object

- to

- Mouth 0.0009 lb boron/ft 2 0.0023 3800 2000

Dusts Object

- to

- Mouth 0.00068 lb boron/ft 2 0.0004 20000

--

Hard floors 4 Liquids Hand

- to

- Mouth 0.0009 lb boron/ft 2 0.0043 2000 1400

Dusts Hand

- to

- Mouth 0.00068 lb boron/ft 2 0.0033 2700

-- Liquids Object

- to

- Mouth 0.0009 lb boron/ft 2 0.0012 7600 2600

Dusts Object

- to

- Mouth 0.00068 lb boron/ft 2 0.0009 10000

--

Child Outdoor

(lawn, garden, tree sprays) Granules Hand

- to

- Mouth

1.52 lb ai/acre 0.0023 3800

-- Object

- to

- Mouth 0.00014 63000

-- Soil Ingestion 5.1E

- 05 170000

--

Solid Formulation Ingestion 8% boron

(49% sodium metaborate) 2.36 160

--

0.9% boron (5% boric acid) 0.24 1500

--

Liquids Hand

- to

- Mouth

0.003 lb ai/acre 0.00005 19000

--

Object

- to

- Mouth 0.000001 6300000

-- Soil Ingestion 1E

- 07 8.7E07

--
1 Based on registered labels outlined in Table 4.1. All rates expressed in terms of boron , except where application rate expressed is expressed in terms of the compound with the highest rate

– disodium octaborate tetrahydrate (DOT)

– in order to calculate volatilization of sprays using molecular weight and vapor pressure parameters.

2 Dose (mg /kg/day) algorithms provided in 2012 Residential SOPs ( http://www.epa.gov/pesticides/science/residential

- exposure

- sop.html ). Expressed in terms of boron.

3 MOE = POD (mg/kg/day) ÷ Dose (mg/kg/day).

4 As described in Section 5.2, transferability from carpet and hard floors following dust treatments estimated at 0. 1% an d 0. 4% respectively and transferability following liquid treatments on carpets and hard floor s estimated at 0.4%.

5 Combined MOE = POD (mg/kg/day) ÷ [Inhalation Dose + Oral Dose (mg/kg/day) ]

. Combined exposures are only applicable for children 1< 2. When a combined MOE is shown the inhalation component is via the scenario for liquid applications to carpet or hard floors (d ose = 0.0022 mg/kg/day, MOE=4000).



### 5.3 Residential Risk Estimates for Use in Aggregate Assessment

Table 5.3.1 reflects the r esidential risk estimates from the conventional pesticide uses of boric

acid and its sodium salts that are recommended for use in an aggregate assessment for boric acid

and its sodium salts

. The residential scenarios recommended for the aggregate assessme nt arePage 28 of 60



### generally the short

- /intermediate

- term scenarios with the highest exposure , except for the following situations :

 When the solid formulation ingestion scenario yields the highest exposure

– the episodic

nature of this scenario scenario is not applic able for aggregation with chronic dietary

exposure ; and,

 Scenarios with risk estimates of concern would by default not apply to a quantitative aggregate assessment until they are refined or mitigated. In those cases an aggregate scenario would also presen t a risk of concern.

Thus, for boric acid/sodium salts, the recommended scenarios for potential aggregation are the following:

 The recommended residential exposure for use in an adult aggregate assessment reflects inhalation exposure from indoor applica tions of dust formulations with a shaker can (dose = 0.05 mg/kg

- day, MOE = 180)

.

 The recommended residential exposure s for use in a children 1<2 years old aggregate

assessment reflects the combined exposures from post

- application inhalation (0.0022 mg/kg

- d ay) and hand

- to

- mouth exposures (0.0 43 mg/kg

- day) following ge neral indoor liquid applications to hard floors.

 P ost

- application combined inhalation plus hand

- to

- mouth exposures following general indoor spray treatments to carpets and bed bug treatments to carpets using liquid formulations already presents risk s of concern so would not be applicable for aggregate

risk assessment until r isk s are mitigated.

 Residential risk estimates resulting from antimicrobial pesticide use are addresse d separately and may also impact the aggregate risk assessment

.

Table 5. 3 .1. Recommendations for the Residential Exposures for the Boric Acid/Sodium Salt Aggregate Assessment.

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

Inhalation Oral Total Inhalation Oral Total

Adult Indoor/dust/shaker can 0.05 N/A N/A 180 N/A N/A

Child Indoor/liquids/carpets

and hard floors 0.0022 0.0 43 0.04 5 2 4000 200 190

1 Dose = the highest dose for each applicable lifestage of all residential scenarios assessed

. For adults, inhalation is the only applicable

route. For children t otal dose = inhalation + incidental oral

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



### 6

. 0 Non

- Occupational Spray Drift Exposure and Risk 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 ex posures to those it may 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 riskPage 29 of 60



### est imates from these residues 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 pre mise of compliant applications which, by definition, should not result in direct exposures to individuals because of existing label language and other regulatory requirements intended to prevent them. 9 

### Direct exposures would include inhalation of the spra y plume or being sprayed 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) and 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.

Boric acid and its sodium salts ha ve existing direct uses on turf, thus it was considered whether the risk assessment for that use may be health protective of exposure s resulting from spray drift. If the maximum application rate on crops adj usted by the amount of drift expected is less than or equal to existing turf application rates, the existing turf assessment is considered protective of spray drift exposure. The existing maximum single application rate of boric acid/sodium salts

for vari ous agricultural food/feed crops is 0.0018 lb ai/acre. The highest degree of spray drift noted for any application method immediately adjacent to a treated field (Tier 1 output from the aerial application using fine to medium spray quality) results in a d eposition fraction of 0.26 of the application rate.

A quantitative spray drift ass essment for boric acid/sodium salts is not required because the

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

0.26 is les s than the maximum direct spray residential turf application rate of 0.003 lb ai/acre (i.e., 0.0018 lb ai/A x 0.26 ≤ 0.003 lb ai/A ) . The turf post

- application MOEs based on the revised SOPs for Residential Exposure Assessment were assessed (see above in S ection 5.2) and

n o risks of concern were identified

.

7

. 0 Non

- Occupational Bystander Post

- Application Inhalation Exposure and Risk

Estimates

Volatilization of pesticides may be a source of post

- application inhalation exposure to individuals nearby 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 has evaluated the SAP report and has developed a Volatilization Screening Tool and a subsequent Volatilization Screening Analysis (http://www.regulation s.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) or further analysis are required for boric acid and its sodium salts

.

9 

### 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 30 of 60



### Exposure from volatilization o f indoor sprays resulting from residential applications were considered and are outlined in Section 5.2 above. No risks of concern were identified.

8 .0 Occupational Exposure and Risk Estimates

There are numerous conventional uses of boric acid or its sodium salts as active ingredients, from insecticide and fungicide dusts and sprays to granular herbicides. Additionally, there are antimicrobial uses in swimming pools and as material and wood preservatives.

Given these uses, both occupational handler a nd post

- application exposures are anticipated. As described above, though dermal exposures are possible, due to negligible dermal absorption, toxicity from dermal exposure is not expected and dermal risks are not of concern. Therefore,

addressed below ar e inhalation exposures for workers mixing/loading and applying boric acid products as well as post

- application inhalation resulting from areas previously treated with boric acid products

.

I nhalation exposures for some occupational handler scenarios have risk estimates of concern (MOEs < 100), requiring respirator s to mitigate risks. For dust applications to structural building components (e.g., attics, crawl spaces, soffits, etc.) and agricultural bu ildings (e.g., poultry houses) , standard respirator s (i.e., filtering face

- pieces) do not mitigat e inhalation risk estimates

of concern . No post

- application risks are of concern

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 on the specifics of each task. Job requirements (am ount 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.

The quantitative exposur e/risk assessment developed for occupational handlers is based on the following scenarios

.

 L oading granules to support tractor

- drawn spreader applications

 Mixing/loading liquids to support applications via:

o Airblast sprayers

o Groundboom sprayers

 Loading/ap plying granules with :

o Backpacks

o Belly grinders

o Spoons or cups

o Rotary spreaders

 Mixing/loading/applying liquid solutions with :

o Airless sprayerPage 31 of 60 

### o Brush/roller

o Backpack sprayers

o Manually

- pressurized handwand sprayers

o Mechanically

- pressurized handgun sprayers

 Mixing/loading dusts/powders with water and applying with m anually pressurized

handwands and m echanically pressurized handguns

 Applying bait gels/pastes

 Applying dusts with :

o Shaker cans

o Bulb dusters

o Plunger dusters

o Power dusters/blowers

 Applying granules v ia :

o Hand dispersal

o Tractor

- drawn spreaders

 Applying sprays with :

o Airblast sprayers

o Groundboom sprayers

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.

Application Rate :

The application rate used in this assessment is provided in Section 4.0 (Table 4.1)

.

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 ORETF database, or other registr ant

- 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 asses sment, known as “unit exposures”, are outlined in the “Occupational Pesticide Handler Unit Exposure Surrogate Reference Table 10 

### ”, 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 11



### .

Area Treated or Amount Handled :

The inputs for area treated or amount of solution or product handled were based on ExpoSAC Policy 9.1. The following summarizes the inputs used fo r estimating handler exposures:

10 Available: h ttp://www.epa.gov/opp00001/science/handler

- exposure

- table.pdf

11 Available: http://www.epa.gov/pesticides/science/handler

- exposure

- data.htmlPage 32 of 60



###  10,000 square feet (0.23 acres) for :

o H and dispersal of granules in food handling establishments or residential living

spaces

o Dust applications with plunger or power/blower dusters to industrial/commercial

areas, poultry houses , and structural building comp onents

o Dust applications with a bulb duster to food handling establishments, warehouses, and residential living spaces

 1 acre for:

o Hand dispersal of granules to grass, industrial/commercial areas, building foundations/perimeters, and ant mounds

o Backpack ap plication of granules to industrial/commercial areas

o Belly grinder application of granules to grass, building foundations/perimeters,

and industrial/commercial areas

o Spoon or cup applications to building foundations/perimeters and

industrial/commercial are as

 1 (20 oz.) container of dust for shaker can and bulb duster applications to greenhouses, nurseries, landscaping, warehouses, poultry houses , building foundations/perimeters, interior landscaping, food handling establishments, residential living spaces, and schools

 5 acres for:

o Liquid spray applications with a groundboom sprayer to golf course te e s and

greens

o Mechanically

- pressurized handgun applications of liquid sprays to grass (lawns, athletic fields, parks, etc.)

o Granule applications via rotary spread er to golf course turf, ant mounds, grass (lawns, athletic fields, parks, etc.), and industrial/commercial areas

 20 acres for airblast applications to nurseries

 40 acres for:

o Tractor drawn spreader applications of granules to golf course turf and grass (lawns, athletic fields, parks, etc.)

o Airblast applications to orchard s /vineyards

o Groundboom application of liquid sprays to golf course fairways, tees, and

greens , field

- grown ornamental crops, and orchards/vineyards

 40 gallons for:

o Backpack application t o orchards/vineyards, greenhouses, nurseries, landscaping (grass, flowers, trees), and structural building components

o Manually

- pressurized handwand greenhouses, nurseries, landscaping (grass, flowers, trees), residential living spaces , and structural build ing components

o Airless sprayer and brush/roller application of solutions to structural building

components

 60 acres for:

o Granule applications via tractor drawn spreader to industrial/commercial areas

o Groundboom application to greenhouses and nurseries

 80 a cres for groundboom application to typical

- acreage field crops

 200 acres for groundboom application to high

- acreage field crops

 1000 gallons for m echanically

- pressurized handgun applications to orchards/vineyards,Page 33 of 60



### greenhouses, nurseries, landscaping, struc tural building components, typical

- acreage field crops, and poultry houses

 1000 square feet (0.023 acres) for application to tree stumps (equivalent to approximately 100 tree stumps each with a diameter of 4 feet)

Exposure Duration:

HED typically clas sifies 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 pesticid e, 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 large agribusiness and/or commercial applicators who may apply a produ ct over a period of weeks (e.g., completing multiple applications for

mult iple clients within a region).

Additionally, given that labels for boric acid and its sodium salts products general ly do not specify retreatment intervals and its nature as a multi

- use pesticide (as an insecticide, herbicide, and fungicide), it is not unreasonable to consider applicators handling this active ingredient relatively frequently. Thus, both short

- and inte rmediate

- term exposures are anticipated. However, the toxicological endpoint selected for the short

- term assessment is protective of both

short

- and intermediate

- term durations

.

Mitigation/Personal Protective Equipment:

Product labels vary with respect to work attire and levels of personal protective equipment, with some labels not providing any specifications to others requiring use of chemical/water

- resistant gloves or respirators.

As previously described, dermal tox icity was not identified so dermal risks are not quantified in

this section. Dermal exposure

- related work attire and PPE (e.g., chemical

- resistant gloves)

should therefore be considered in the context of end

- use

- product acute toxicity requirements.

Inhal ation exposure is assessed assuming no respiratory protection and then, when risks of concern might indicate a need for them, assessed assuming different types of respirators. Respiratory protection requirements, beyond end

- use

- product acute toxicity requ irements, should

be considered for certain scenarios as described in this section.

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 Estimates As no dermal hazard was identified, there is no combination of dermal and inhalation exposures for risk assessment purposes.

Summary of Occupational Handler Non

- Cancer Exposure and Risk EstimatesPage 34 of 60



### The occupational handler exposure and risk estimates indicate th e following scenarios have

inhalation risk estimates of concern (MOEs < 100) without respiratory protection:

 L oading granules to support tractor

- drawn spreader applications in industrial/commerci al

areas

 Applying granules to industrial/commercial areas via:

o Hand dispersal

o Tractor

- drawn spreaders

o Spoons or cups

 Applying dusts with:

o Bulb dusters to food handling establishments, warehouses, residential living spaces, and structural building components

o Plunger dusters to structural building components

o Power dusters/blowers poultry houses

o Shaker cans to tree stumps

 Mixing/loading/applying liquid solutions with mechanically

- pressurized handgun sprayers and airless sprayers to structural building components

 Mixing/loading dusts/powders with water and applying with :

o M echanically pressurized handguns to poultry houses

o Manually pressurized handwands to residential living spaces and structural building components

Hand dispersal of granules in industr ial/commercial areas and shaker can applications of dusts to tree stumps do not result in risk estimates of concern (MOE > 100) with a respirator that offers 90% reduction in inhalation exposure (e.g., a half

- face cartridge/canister style mask) . All other scenarios of concern without a respirator do not result in risk estimates of concern with a respirator that offers 80% reduction in inhalation exposure ( e.g. a quarter

- face dust/mist filtering face mask)

.

For the following two scenarios, inhalation expos ures are of a magnitude that no standard respiratory protection 12 

### reduces exposures to a level where inhalation risks are not of concern (MOEs ≥ 100) :

 Applying dusts with:

o Plunger dusters to structural building components and poultry houses

o Power dusters/blowers to poultry houses

Overall, application rates for boric acid/sodium salts products are relatively high

– for the scenarios above, some on the order of 100 pounds of active ingredient or more per acre or almost 1⁄2 pound of active ingredient p er gallon of dilute solution. These h igh application rates , as well as, for applicable scenarios, the fact that exposure data indicates dust formulations present some of the highest inhalation exposures

, is driving the presence of inhalation risks.

12 While a self

- contained breathing apparatus or a powered

- air supply respirator will likely sufficiently reduce exposures, it is assumed that these are infeasible/impractical options.Page 35 of 60



### Final ly, a ll inhalation risk estimates

– those of concern and not of concern

– should be considered in concert with existing labels that require respirators under certain conditions as well

as the default end

- use product acute toxicity

- based respiratory protect ion requirements.

Table 8 .1.1 presents detailed exposure and risk calculations.Page 36 of 60

Table 8.1.1. Summary of Occupational Handler Risk Estimates for Boric Acid and its Sodium Salts

Exposure

Scenario Crop / Target Category App Rate 1 Amount

Handled/ Area

Treated 2 I nhalation 3

Unit Exposure ( u g/lb ai) 4 Dose

(mg/kg/day) 5 MOE 6

(LOC = 10 0 )

Mixing / loading / applying

l iquids Backpack

sprayer Nursery, Landscaping (turf,

trees, plants) 0.000073 lb

ai/ gallon dilute

solution

40 gallons dilute

solution 69.1 2.5E

- 06 3,500,000

Greenhouse 140 5.1E

- 06 1,700,000

Structural Building Components 0.32 lb ai/gallon

dilute solution 30 0.0048 1800

Manually

pressurized

Handwand Residential Living Spaces 0.1 5 lb ai/gallon

dilute solution 1100 0.083 110

Nursery, Landscaping (turf, trees, plants), Greenhouse

0.000073 lb

ai/ gallon dilute

solution 40 gallons dilute

solution 30 1.1E

- 06 8,000,000

Mechanically

pressurized handgun Field Crops (typical

acreage), Landscaping (trees, plants), Nursery, Orchards/vineyards 1000 gallons

dilute solution 8.68 7.9E

- 06 1,100,000

Greenhouse 120 1.1E

- 04 80,000

Structural Building Components 0.32 lb ai /gallon

dilute solution 79 (NR) 15.8 (PF5) 0.316 (NR)

0.063 (PF5) 28 (NR)

140 (PF5)

Landscaping (turf) 0.003 lb ai/acre 5 acres 1.9 3.6E

- 07 25,000,000

Airless sprayer Structural Building Components 0.32 lb ai/gallon

dilute solution 40 gallons dilute

solution 560 (NR)

112 (PF5) 0.09 (NR)

0.018 (PF5) 98 (NR)

490 (PF5)

Brush/roller 280 0.045 200

Mixing / loading / applying Mechanically

pressurized handgun Poultry house 0.15 lb ai/gallon

dilute solution 1000 gallons

dilute solution 79 (NR)

15.8 (PF5) 0.149 (NR)

0.03 (PF5) 59 (NR)

300 (PF5)Page 37 of 60

Table 8.1.1. Summary of Occupational Handler Risk Estimates for Boric Acid and its Sodium Salts

Exposure

Scenario Crop / Target Category App Rate 1 Amount

Handled/ Area

Treated 2 I nhalation 3

Unit Exposure ( u g/lb ai) 4 Dose

(mg/kg/day) 5 MOE 6

(LOC = 10 0 )

wettable

dusts/ powders Manually

pressurized

Handwand Residential Living Spaces 0.18 lb ai/gallon

dilute solution 40 gallons dilute

solution 1100 (NR)

220 (PF5) 0.099 (NR)

0.0198 (PF5) 89 (NR)

440 (PF5)

Structural building

components 0.31 lb ai/gallon

dilute solution 1100 (NR) 220 (PF5) 0.17 (NR)

0.0341 (PF5) 52 (NR)

260 (PF5)

Tree stumps 0.0023 lb ai/ft 2 1,000 ft 2 of tree

stumps 30 0.00085 10,000

Loading/ applying

dusts Bulb duster Crack and crevice (residential areas, warehouses, food handling establishments) 0.00068 lb ai/ft 2 10,000 ft 2
1690 (NR) 338 (PF5) 0.144 (NR)

0.029 (PF5) 61 (NR)

310 (PF5)

0.22 lb ai/20 oz

container One 20 oz

container 0.0047 1900

Plunger duster Structural building

components 0.0065 lb ai/ft 2 10,000 ft 2

1690 (NR) 338 (PF5) 169 (PF10) 1.38 (NR)

0.275 (PF5) 0.138 (PF10) 6.4 (NR)

32 (PF5) 64 (PF10)

Industrial/commercial areas 0.00068 lb ai/ft 2 10,000 ft 2 0.144 (NR) 0.029 (PF5) 61 (NR)

310 (PF5)

Poultry house 0.01 lb ai/ft 2 10,000 ft 2 2.18 (NR) 0.435 (PF5) 0.218 (PF10) 4 (NR)

20 (PF5) 40 (PF10)

Power

duster/blower Poultry house 0.01 lb ai/ft 2 10,000 ft 2 17,500 (NR) 3500 (PF5) 17500 (PF10) 22.5 (NR)

4.5 (PF5) 2.25 (PF10) < 1 (NR)

2 (PF5) 4 (PF10)

Shaker can Greenhouse, Nursery,

Landscaping (plants/flowers), Warehouse, Poultry house,

Foundations/Perimeters 0.22 lb ai/20 oz

container One 20 oz

container 17,500 (NR)

3500 (PF5) 17500 (PF10) 0.048 180

Tree stumps 0.0023 lb ai/ft 2 1,000 ft 2 of tree

stumps 0.495 (NR) 0.099 (PF5) 0.05 (PF10) 18 (NR)

89 (PF5) 180 (PF10)Page 38 of 60

Table 8.1.1. Summary of Occupational Handler Risk Estimates for Boric Acid and its Sodium Salts

Exposure

Scenario Crop / Target Category App Rate 1 Amount

Handled/ Area

Treated 2 I nhalation 3

Unit Exposure ( u g/lb ai) 4 Dose

(mg/kg/day) 5 MOE 6

(LOC = 10 0 )

Mixing / loading liquids Groundboom Golf course (tees and greens)

0.0018 lb ai/acre 5 acres

0.219 2.5E

- 08 360,000,000

Golf course (fairways, tees, and greens), Field

- grown ornamentals, Orchard/vineyards 40 acres 2.0E

- 07 44,000,000

Nursery, Greenhouse 60 acres 3.0E

- 07 30,000,000

Field crops (typical acreage) 80 acres 3.9E

- 07 22,000,000

Field crops (high acreage) 200 acres 9.9E

- 07 8,900,000

Airblast Nursery 20 acres 9.9E

- 08 89,000,000

Orchards/vineyards 40 acres 2.0E

- 07 44,000,000

Applying

sprays Groundboom Golf course (tees and greens)

0.0018 lb ai/acre 5 acres

0.34 3.8E

- 08 230,000,000

Golf course (fairways, tees, and greens), Field

- grown ornamentals, Orchard/vineyards 40 acres 3.1E

- 07 29,000,000

Nursery, Greenhouse 60 acres 4.6E

- 07 19,000,000

Field crops (typical acreage) 80 acres 6.1E

- 07 14,000,000Page 39 of 60

Table 8.1.1. Summary of Occupational Handler Risk Estimates for Boric Acid and its Sodium Salts

Exposure

Scenario Crop / Target Category App Rate 1 Amount

Handled/ Area

Treated 2 I nhalation 3

Unit Exposure ( u g/lb ai) 4 Dose

(mg/kg/day) 5 MOE 6

(LOC = 10 0 )

Field crops (high acreage) 200 acres 1.5E

- 06 5,800,000

Airblast Nursery 20 acres

4.71 2.1E

- 06 4,100,000

Orchards/vineyards 40 acres 4.2E

- 06 2,100,000

Mixing/ loading granules Tractor drawn

spreader Golf course (fairways, tees,

and greens) 1.5 lb ai/acre 40 acres 1.7 (NR) 0.34 (PF5) 0.0013 6900

Industrial/commercial areas 105 lb ai/acre 60 acres 0.134 (NR) 0.027 (PF5) 66 (NR)

330 (PF5)

Applying granules/

baits Hand dispersal Residential areas, food handling establishments 0.017 lb ai/1000 ft 2 10,000 ft 2

470 (NR) 94 (PF5) 47 (PF10) 0.001 8500

Foundations/perimeters 1.5 lb ai/acre

1 acre 0.009 1000

Industrial/commercial areas 105 lb ai/acre 0.618 (NR) 0.123 (PF5) 0.062 (PF10) 14 NR)

72 (PF5) 140 (PF10)

Belly grinder Landscaping (turf),

Foundations/perimeters 1.5 lb ai/acre 1 acre

62 0.0012 7600

Industrial/commercial areas 105 lb ai/acre 1 acre 6.51 110

Tractor drawn spreader Golf course (fairways, tees,

and greens) 1.5 lb ai/acre 40 acres 1.2 (NR) 0.24 (PF5) 0.0009 9800

Industrial/commercial areas 105 lb ai/acre 60 acres 0.095 (NR)

0.019 (PF5) 93 (NR)

470 (PF5)Page 40 of 60

Table 8.1.1. Summary of Occupational Handler Risk Estimates for Boric Acid and its Sodium Salts

Exposure

Scenario Crop / Target Category App Rate 1 Amount

Handled/ Area

Treated 2 I nhalation 3

Unit Exposure ( u g/lb ai) 4 Dose

(mg/kg/day) 5 MOE 6

(LOC = 10 0 )

Rotary spreader Golf course (fairways, tees,

and greens), Landscaping

(turf) 1.5 lb ai/acre 5 acres

10 0.0009 9400

Industrial/commercial areas 105 lb ai/acre 5 acres 0.066 130

Spoon Foundations/perimeters 1.5 lb ai/acre 1 acre 121 (NR) 24.2 (PF5) 0.0023 3900

Industrial/commercial areas 105 lb ai/acre 1 acre 0.159 (NR) 0.032 (PF5) 55 (NR)

280 (PF5)

Cup Foundations/perimeters 1.5 lb ai/acre 1 acre

12.5 0.00024 37000

Industrial/commercial areas 105 lb ai/acre 1 acre 0.0164 5400

Backpack Industrial/commercial areas 105 lb ai/acre 1 acre 23.8 0.031 280

Applying gels/pastes Crack and crevice (residential areas,

warehouses, food handling establishments) No exposure/risks expected from gel/paste formulations.

1 Based on registered label on registered labels outlined in Table 4.1. All rates expressed in terms of boron.

2 Exposure Science Advisory Council Policy #9.1 and information provided on labels

3 NR = no respirator; PF5 = “Protection Factor 5”, indicating a reduction in exposure of 80% ; PF10 = “Protection Factor 10” indicating a reduction in exposure of 90%. Unless noted, results reflect no respirator (NR).

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

5 Inhalation Dose = Inhalation Unit Exposure (μg/lb ai) × Conversion Factor (0.001 mg/μg) × Application Rate (lb ai/acre) × Area Treated ( A/day) ÷ BW (kg). Expressed in terms of boron.

6 Inhalation MOE = Inhalation POD (mg/kg/day) ÷ Inhalation Dose (mg/kg /day )Page 41 of 60



### 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 addition, the timing of pesticide applications,

relative to harvest acti vities, 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

- app lication activities in previously treated fields. These potential sources include volatilization of pesticides and resuspension of dusts and/or particulates that contain pesticides. The agency sought expert advice and input on issues related to volatiliza tion 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 a gency 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) or further analysis is required for boric acid/sodium salts

.

In addition, the A gency 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.

For applications within greenhouses, t he Worker Protection Standard for Agricultural Pesticides contains requirements for protecting workers from inhalation exposures du ring and after greenhouse applications through the use of ventilation requirements [40 CFR 170.110, (3) (Restrictions associated with pesticide applications)] . Additionally, c ommercial applicators do not typically return to the treated areas after an indo or commercial pesticide application (sites such as warehouses, food handling establishments, and hotels, etc.) and thus an occupational

post

- application inhalation exposure assessment was not perfo rmed for commercial applicators

.

8

. 2 .2 Occupational Post

- a pplication Dermal Exposure/Risk Estimates

Dermal exposure s are possible for workers re

- entering treated areas (e.g., agricultural crops), however, a s no systemic dermal toxicity was identified, occupational de rmal risks are not of

concern.Page 42 of 60



### Restricted

- ent ry intervals (REIs) therefore default to technical grade active ingredient acute toxicity

- based requirements. Currently, REIs on product labels vary considerably from 4 hours to 48 hours. These differences may reflect the different acute toxicity profile s of the various borate sodium salts, or the presence of an additional active ingredient in the product. REIs

should be reconciled with the acute toxicity

- based requirements.

Products having 4 hour REIs should be reviewed to be sure they meet certain cri teria in accordance with the Pesticide Registration (PR) Notice 95

- 3 [Reduction of WPS Interim REIs for Certain Low Risk Pesticides] 13 

### . In PR Notice 95

- 3, there are a set of criteria listed for the active ingredient that must be met for chemicals to be eli gible for a reduced REI. These criteria

include:

1. The active ingredient is in Toxicity category III or IV based upon data for acute dermal toxicity, acute inhalation toxicity, primary skin irritation, and primary eye irritation. Acute oral toxicity data w ere used if no acute dermal data were available. If EPA lacked data on primary skin irritation, acute inhalation, or primary eye irritation of the active ingredient, the Agency reviewed data on that end

- point for similar active ingredients (analogs), and e xcluded such active ingredients from consideration for the reduced REI, if the analog is in Toxicity Category I or II for that endpoint.

2. The active ingredient is not a dermal sensitizer (or in the case of biochemical and microbial active ingredients, no known reports of hypersensitivity exist).

3. The active ingredient is not a cholinesterase inhibitor (NMethyl carbamate and Organophosphate) as these chemicals are known to cause large numbers of pesticide poisonings and have the potential for serious neurological effects.

4. No known reproductive, developmental, carcinogenic, or neurotoxic effects have been

associa ted with the active ingredient. If active ingredients did not have data available for these chronic health effects, EPA considered data on appropriate chemical and biological analogs. Active ingredients that have been classified as carcinogenic in Category B (probable human carcinogen) or Category C with a potency factor, Q* (possible human carcinogen, for which quantification of potential risk is considered appropriate), or are scheduled for the Health Effects Division's Cancer Peer Review process, were om itted

from consideration.

5. EPA does not possess incident information (illness or injury reports) that are “ definitely ” or “probably” related to post

- application exposures to the active ingredient.

Upon review of the criteria for boric acid and its sodium s alts, it appears that they are not

consistent with the criteria in PRN 95

- 3 that allow for a 4

- hour REI , based primarily on the prevalence of acute toxicity category I for eye irritation

. Note that similar criteria apply to the acute toxicity of the end

- u se product s, but HED has only evaluated the 4 hour REI in the context of the acute toxicity of the active ingredients

.

13 Available: http://www.epa.gov/PR_Notices/pr95

- 3 .htmlPage 43 of 60



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

- cancer Algorithms

RESIDENTI AL NON



## - CANCER HANDLER ALGOR ITHMS



### 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 b y 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 exposure (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 w eight (kg).

RESIDENTIAL NON



## - CANCER POST



## - APPLICATION ALGORITH MS



### 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 assessment 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 44 of 60



### 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 immediately after application). However, if data are not available, then TTR t 

### can be calcula ted 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 

### acr e/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

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

AR Application rate (mass active ingredient per unit area) [input]

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 45 of 60

Table A

- 1 : Turf (Physical Activities)

-- Inputs for Residential Post

- application Dermal 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 factor (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 46 of 60



### 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) [input]

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 per 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).Page 47 of 60



### and

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 = a rea 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) [input]

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:Page 4 8 of 60



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

SRt = soil residue on day "t" (μg/g); 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 uni t 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) [input]

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:Page 49 of 60 

### E = GIgR* FD * CF1

where: 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, a re 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 [input]

AR Application rate (lbs/A or lbs/1,000 ft 2 ) [input]

GIgR Granule ingestion rate per day (g/day) 1 0.3

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.



### Turf/Mowing

Post

- application Dermal Exposure Algorithm

– Mowing Exposure resulting from contacting previously treated turf while mowing is calculated as

follows:

E = TTRt * CF1 * TC * ET

where :

E = exposure (mg/day);

TTR t 

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

### ); CF1 = weight unit conversion factor (0.001 mg/μg); TC = transfer coefficient (cm 2 

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

andPage 50 of 60 

### TTRt = AR * F

AR 

### * (1

- F

D 

### ) t 

### * CF2 * CF3

where :

TTR t 

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

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

### or lb ai/acre);

F AR 

### = fraction of ai retained on turf (unitless);

F D 

### = fraction of residue that dissip ates 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 

### ).

Absorbed dose, normalized to body weight, are calculated as:

where :
D = dose (mg/kg

- day);

E = exposure (mg/day);

AF = absorption factor (dermal); and

BW = body weight (kg).

Table A

- 6 : Turf (Mowing)

– Inputs for Residential Post

- application Dermal Exposure

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

AR Application rate mass active ingredient per unit area [input]

F AR Fraction of AR as TTR following application L/WP/WDG 0.01

Granules 0.002

F D Daily residue dissipation L/WP/WDG 0.1

Granules 0.1

TC Transfer Coefficient (cm 2 /hr) Adult 5,500

Children 11 < 16 years

old 4,500

ET Exposure time (hours per day) 1

BW Body Weight (kg) Adults 80

Children 11 < 16 years

old 57

L/WP/WDG = liquid/wettable powder/water dispersible granule



### Post

- Application Inhalation Exposure AlgorithmsPage 51 of 60



### Exposure to pesticide vapors The following algorithm is used to determine post

- application inhalation exposure from indoor

surface

- directed sprays:

E = IR ∗ M label


### ACH ∗ V

room 

### [ 1

− ( ( ACH ∗ e − k ∗ ET 

### )

− ( k ∗ e − ACH ∗ ET



### ACH

− k ) ]

where :
E = exposure (mg/day);

IR = inhalation rate (m 3 

### /hr);

M label 

### = mass of active ingredient applied, determined from product label (mg);

V room 

### = volume of room (m 3 

### );

ACH = air exchanges per hour (1/hr );

k = first order decay rate (1/hr); and

ET = exposure time (hr).

In the above equation, a mass of pesticide is applied to a surface and the emission of the pesticide from the surface is assumed to decline over time due to dissipation of the pesticide (i .e., emission from the treated surface and removal due to the air exchange rate). The mass of active ingredient applied can be calculated using the following formula:

M label 

### = AR ∗ A ∗ CF 1

where:

M label 

### = mass of active ingredient applied, determined from product label (mg);

AR = application rate (e.g., lb ai/ft 2 

### , lb ai/gal);

A = area treated or amount handled (e.g., ft 2 

### /day, gal/day); and

CF1 = conversion factor (4.54x10 5 

### mg/lb).

The exposure equation models an emission rate that decrease s over time, which is based on a

first

- order decay rate constant (k). Evans (1994) proposed calculating such a decay rate based on work done by Chinn (1981). Chinn developed the following relationship between the volatility, or saturation concentration ( C sat 

### ), of a chemical and the time required for 90% of the chemical to evaporate (EvapT):

EvapT = 10 [ 7

. 3698

− 0

. 9546 ∗ log 10 ( C sat ) ]



### where : EvapT = evaporation time (sec); and

C sat 

### = saturation concentration (mg/m 3 

### ).Page 52 of 60



### Evans proposed the following equation to calculate the decay rate (or dissipation rate) that defines the change in the emission rate based on the evaporation time described by Chinn:

k = ln ( 0

. 1 ) ∗ CF 1

EvapT

where : k = first order decay rate (1/hr),

CF1 = conversion factor (sec /hr), and EvapT = evaporation time (sec).

**Saturation concentration verification** In the vapor emission assessment, post

- application inhalation exposure occurs from the release of vapors following a surface treatment indoors. The concentration of pesti cide in the air is modeled over time to calculate exposure. The maximum concentration allowed in the air should be the saturation concentration, calculated as a function of the pesticide’s molecular weight and vapor pressure. The equation used to model t he air concentration is not bound by the saturation concentration; therefore, the reviewer must perform a check to make sure the exposures being calculated are valid.

The exposure equation above is based on the mass of pesticide applied, not the concentration of the pesticide in the air; therefore, the reviewer must check that the input for mass applied (M label 

### ) is predicting an air concentration less than or equal to the saturation concentration. The following equation can be used to calculate t he theoretical mass applied that would result in an air concentration that reaches the saturation concentration for a pesticide (M Csat 

### ):

M C sat 

### = C

sat 

### ∗ ( ACH

− k ) ∗ V

k

M Csat 

### should be compared to M label



### .

 If M label 

### > M Csat 

###  M label 

### will predict an air concentration higher than the saturation

concentration. Use M Csat 

### in the exposure calculation.

 If M label 

### < M Csat 

### ,  M label 

### will not predict an air concentration higher than the saturation

concentration. Use M label 

### in the exposure calcu lation.

Once the post

- application inhalation exposure is calculated, the inhalation dose normalized to body weight is calculated as:

D = E ∗ AF

BWPage 53 of 60



### where :

D = dose (mg/kg

- day);

E = exposure (mg/day);

AF = absorption factor (inhalation); and

BW = body weight (kg).

Table A

- 7 : Indoor Environments

– Inputs for Residential Post

- applica tion Inhalation Exposure Algorithm

Notation Exposure Factor (units) Point Estimate(s)

Generic Variables Used in Calculating Post

- application Inhalation Exposure

IR Inhalation rate

(m 3 /hour) Adult 0.64 Children 1 < 2 years old 0.33

ACH Air changes per hour (hr

- 1 ) 0.45

BW Body weight

(kg) Adult 80

Children 1 < 2 years old 11

V
room Volume of room (m 3 ) 33

Variables Specific to Post

- application Inhalation Exposure to Pesticide Aerosols

C
o Initial air concentration (mg/m 3 ) Calculated; concentration at

time “0”

AR Application rate (lb ai/ ft 3 ) [input]

A.I. Percent ai in product (%) [input]

V product Volume of product (mL) [input]

D product Product density

(g/mL) Water

- based products 1

Solvent

- based products 0.8

ET Exposure time (hr/day) 2

Variables Specific to Post

- application Inhalation Exposure to Pesticide Vapors

C sat Saturation concentration (mg/m 3 ) Calculated

VP Vapor pressure (mmHg) [input]

MW Molecular weight (g/mol) [input]

R Gas constant (L

- atm/mol

- K) 0.0821

T Temperature of the air (kelvin, K) 298



### M label Mass of active ingredient applied (mg) [input]

k First order decay rate Calculated

ET Exposure time

(hr/day) Adult 16

Children 1 < 2 years old 18Page 54 of 60



### Post

- Application Dermal Exposure Algorithm (hard surfaces and carpets) The algorithm to calculate exposure is as follows:

E = TR ∗ TC ∗ ET ∗ CF 1

where :
E = exposure (mg/day);

TR = indoor surface transferable residue (μg/cm 2 

### );

TC = transfer coefficient (cm 2 

### /hr);

ET = exposure time (hr/day); and

CF1 = conversion factor (0.001 mg/μg).

If chemical

- specific TR data are available, this is preferred and should be used to calculate exposure. However, if chemical

- specific TR data are not available, then TR can be calculated using the following formula:

TR = DepR ∗ F ai



### where :
TR = indoor surface transferable residue (μg/cm 2 

### ); DepR = deposited residue (  g/cm 2 

### ), based on (in order of preference):

(1) Chemical

- specific residue deposition data (  g/cm 2 

### ), (2) Application rate (lb ai/area), or (3) Default residue based on type of application (  g/cm 2 

### ); and

F ai 

### = fraction of ai available for transfer from carpet or hard surface (unitless).

Absorbed derma l dose, normalized to body weight, are calculated as:

D = E ∗ AF

BW

where :
D = dose (mg/kg

- day);

E = exposure (mg/day);

AF = absorption factor; and

BW = body weight (kg).

Table A

- 8 : Indoor Environments (Hard Surfaces and Carpets)

– Inputs for Residential Post

- application Dermal Exposure Algorithm

Notation Exposure Factor (units) Point Estimate(s)

TR Transferable residue
(  g/cm 2 ) (1) Chemical

- specific transferable

residue data ORPage 55 of 60

Table A

- 8 : Indoor Environments (Hard Surfaces and Carpets)

– Inputs for Residential Post

- application Dermal Exposure Algorithm

Notation Exposure Factor (units) Point Estimate(s)

(2) Estimated: DepR * F ai

DepR Deposited residue
(  g/cm 2 ) (1) Chemical

- specific residue deposition data, (2) Estimated based on application

rate, or (3) Estimated based on default residue related to type of application

F ai Fraction of DepR as TR

following application Carpets 0.06

Hard surfaces 0.08

TC Transfer Coefficient

(cm 2 /hr) Adult 6,800

Children 1 < 2 years old 1,800

ET Exposure Time (hrs/day) Adults Carpets 8

Hard

Surfaces 2

Children 1 < 2 years old Carpets 4

Hard

Surfaces 2

BW Body weight (kg) Adult 80 Children 1 < 2 years old 11



### Post

- Application Dermal Exposure Algorithm (mattresses) The algorithm to calculate absorbed dose is as follows:

D = DR ∗ SA

BW ∗ F ∗ F

ai 

### ∗ PF ∗ AF ∗ CF 1

where:

D = Dermal dose (mg/kg

- day);

DR = Deposited residue (mg/cm 2 

### );

SA/BW = Surface area / Body Weight Ratio (cm 2 

### /kg);

F = Fraction of body that contacts residue;

CF1 = Conversion factor (mg/  g);

AF = Absorption factor;

F ai 

### = fraction of ai available for transfer from treated mattress; and

PF = Protection factor to account for the presence of a single layer of

fabric (e.g. bed sheet) b etween the treated material and individual.Page 56 of 60

Table A

- 9: Indoor Environments (mattresses)

– Inputs for Residential Post

- application Dermal Exposure

Algorithm

Notation Exposure Factor (units) Point Estimate(s)

DR Deposited residue
(  g/cm 2 ) (1) Calculated based on information provided on

label

OR (2) based on default residue values

SA/BW Surface area / Body Weight

Ratio (cm 2 /kg) Adult 280

Children 1 < 2 years old 640

F Fraction of body that contacts residue 0.5

F ai Fraction of DR available for transfer 0.06

PF Protection Factor 0.5



### Post

- application Hand

- to

- Mouth Exposure Algorithm Exposure from hand

- to

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

SHEDS

- Multimedia):

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 

### );

F M 

### = fraction hand surface area mouthed / event (fraction/event);

ET = exposure time (hr/day);

SA H 

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

### ); N_Replen = number of replenishment intervals per hour (intervals/hour);

SE = saliva extraction factor (i.e., mouthing removal efficiency); and Freq_HtM = number of h and

- to

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

and

HR = Fai h ands 

### ∗ DE

SA H 

### ∗ 2

where :
HR = hand residue loading (mg/cm 2 

### );

Fai hands 

### = fraction ai on hands compared to total surface residue from jazzercise

study (unitless);

DE = dermal exposure (mg); andPage 57 of 60



### SA H 

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

### ).

and

Dose, normalized to body weight, is calculated as:

D = E

BW

where :
D = dose (mg/kg

- day);

E = exposure (mg/day); and

BW = body weight (kg).

Table A

- 10: Indoor Environments

– 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 jazzercise study (unitless) 0.15

DE Dermal exposure (mg) Calculated

HR Residue available on the hands (mg/cm 2 ) Calculated

SA H Surface area of one hand

(cm 2 ) Children 1 < 2 years old 150

AR Application rate (mass active ingredient per unit area) [input]

F M Fraction of hand mouthed per event (fraction/event) 0.13

N_Replen Replenishment intervals per hour (intervals/hr) 4

ET Exposure time

(hours per day) Children 1 < 2 years old Carpets 4

Hard Surfaces 2

SE Saliva extraction factor (fraction) 0.48

Freq_HtM Hand

- to

- mouth events

per hour (events/hr) Children 1 < 2 years old 20

BW Body Weight

(kg) Children 1 < 2 years old 11Page 58 of 60



### Post

- application Object

- to

- Mouth Exposure Algorithm Exposure from object

- to

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

SHEDS

- Multimedia):

E = OR ∗ CF 1 ∗ SAM O 

### ∗ ( ET ∗ N

_ Replen ) ∗ ( 1

− ( 1

− SE ) Freq

_ OtM

N

_ Replen 

### )

where:

E = exposure (mg/day);

OR = chemical residue loading on an object (  g/cm 2 

### );

CF1 = weight unit conversion factor (0.001 mg/  g);

SAM O 

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

### /event);

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

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

- to

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

and

OR = DepR ∗ F O



### where :

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

### ); DepR = deposited residue (μg/cm 2 

### ); and

F O 

### = fraction of residue transferred to an object (unitless).

and

Oral dose, normalized to body weight, is calculated as:

D = E

BW

where :

D = dose (mg/kg

- day);

E = exposure (mg/day); and

BW = body weight (kg).Page 59 of 60

Table A

- 11: Indoor Environments

– Inputs for Residential Post

- application Object

- to

- Mouth Exposure

Algorithm

Notation Exposure Factor (units) Point Estimate(s)

AR Application rate

(mass active ingredient per unit area) [input]

F O Fraction of residue

transferred to an object Carpets 0.06

Hard surfaces 0.08

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 0.48

ET Exposure Time

(hours per day) Children 1 <

2 years old Carpets 4

Hard Surfaces 2

Freq_OtM Object

- to

- mouth events

per hour (events/hour) Children 1 < 2 years old 14

BW Body Weight

(kg) Children 1 < 2 years old 11



### OCCUPATIONAL NON



## - CANCER HANDLER ALGOR ITHMS



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

E=UE * AR * A * 0.001 mg/ug

where:

E = exposure (mg ai /day),

UE = unit exposure (μg ai/lb ai),

AR = maximum application rate according to registered label s (lb ai A

, lb ai/gal , etc. ),

and

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

The daily doses are calculated using the following formula:

ADD= E * AF

BW

where:Page 60 of 60



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

E = exposure (mg ai/day),

AF = absorption factor (dermal and/or inhalation), and

BW = body weight (kg).

Margin of Exposure: Non

- cancer risk estimates for ea ch 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. The daily dermal and inhalation dose received by occupational handlers are compared to the approp riate POD to assess the risk to occupational handlers for each exposure route. All MOE values are calculated using the following formula:

MOE= POD

ADD

where:

MOE = margin of exposure: value used by HED to represent risk estimates (unitless),

POD = point of departure (mg/kg/day), and

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