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UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON, D.C. 20460

OFFICE OF

CHEMICAL SAFETY AND

POLLUTION PREVENTION

MEMORANDUM

DATE: August 22, 2013

SUBJECT: Boscalid – Human Health Risk Assessment for a Section 3 Registration of New 

Uses on Globe Artichoke, Belgium Endive, Persimmon, Greenhouse Grown 

Tomato Transplants for the Home Consumer Market, and Residential 

Ornamentals, Landscape Gardens, Fruit Trees and Nut Trees; Plus Crop Group 

Expansions/Revisions for Bulb Vegetable Group 3-07, Fruiting Vegetable Group 

8-10, Citrus Fruit Group 10-10, Pome Fruit Group 11-10, Berry Subgroups 13-

07A, B, F, and G, Vegetable Root Subgroup 1B Except Sugar beet, and Oilseed 

Group 20.

PC Code: 128008 DP Barcode: D405063, D398877, 406471, D406506

Decision No.: 459294, 470110, 467106, 468292 Registration No.: 7969-199, 7969-251, 7969-GLG, 4-

UII

Petition No.: 2E8068 Regulatory Action: Section 3

Risk Assessment Type: Single Chemical/Aggregate Case No.: NA

TXR No.: NA CAS No.: 188425-85-6

MRID No.: NA 40 CFR: 180.589

FROM: Barry O’Keefe, Senior Biologist

Myron S. Ottley, Senior Biologist

Steve Funk, Senior Chemist

Cassi Walls, Senior Biologist

Risk Assessment Branch III (RAB III)

Health Effects Division (7509P)

THROUGH: Christine Olinger, Branch Chief

Risk Assessment Branch III (RAB III) 

Health Effects Division (7509P)

TO: Heather Garvie, Risk Manager

Dominic Schuler, Risk Manager

Robert Westin, Risk Manager

Fungicide Branch

Registration Division (7505P)

and

Andrew Ertman, Risk Manager

Risk Integration, Minor Use and Emergency Response Branch

Registration Division (7505P)
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This document and attachments provide an assessment of the human health risk resulting from 

the proposed and registered uses of boscalid. The toxicology reevaluation was performed by 

Myron Ottley, the drinking water assessment was conducted by Katrina White (EPA 

Environmental Fate and Effects Division (EFED)), the review of the residue chemistry data an 

dietary exposure assessment were conducted by Steve Funk, the occupational and residential 

exposure assessment was conducted by Cassi Walls, and the human health risk assessment was

conducted by Barry O’Keefe. 
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Table of Contents

1.0 Executive Summary........................................................................................................... 5

2.0 HED Recommendations.................................................................................................... 7

2.1 Data Deficiencies ............................................................................................................ 8

2.2.1 Enforcement Analytical Method ............................................................................... 8

2.2.2 Recommended Tolerances......................................................................................... 8

2.2.3 Revisions to Petitioned-For Tolerances.................................................................. 11

2.2.4 International Harmonization................................................................................... 11

3.0 Introduction...................................................................................................................... 12

3.1 Chemical Identity ......................................................................................................... 13

3.2 Physical/Chemical Characteristics ............................................................................. 14

3.3 Pesticide Use Pattern.................................................................................................... 14

3.4 Anticipated Exposure Pathways................................................................................. 16

3.5 Consideration of Environmental Justice.................................................................... 17

4.0 Hazard Characterization and Dose-Response Assessment.......................................... 17

4.1 Toxicology Studies Available for Analysis................................................................. 17

4.2 Absorption, Distribution, Metabolism and Excretion (ADME) .............................. 18

4.2.1 Dermal Absorption................................................................................................... 18

4.3 Summary of Toxicological Effects.............................................................................. 19

4.4 Safety Factor for Infants and Children (FQPA Safety Factor) ............................... 20

4.4.1 Completeness of the Toxicology Database.............................................................. 20

4.4.2 Evidence of Neurotoxicity........................................................................................ 21

4.4.3 Evidence of Sensitivity/Susceptibility in the Developing or Young Animal........ 21

4.4.4 Residual Uncertainty in the Exposure Database ................................................... 22

4.5.1 Dose-Response Assessment...................................................................................... 22

4.5.2 Recommendation for Combining Routes of Exposure for Risk Assessment ...... 24

4.5.3 Cancer Classification and Risk Assessment Recommendation............................ 24

4.5.4 Summary of Points of Departure and Toxicity Endpoints Used in Human Risk 

Assessment............................................................................................................................... 24

5.0 Dietary Exposure and Risk Assessment......................................................................... 26

5.1 Residues of Concern Summary and Rationale.......................................................... 26

5.2 Food Residue Profile .................................................................................................... 26

5.3 Water Residue Profile.................................................................................................. 28

5.4 Dietary Risk Assessment.............................................................................................. 29

5.4.1 Description of Residue Data Used in Dietary Assessment.................................... 29

5.4.2 Percent Crop Treated Used in Dietary Assessment .............................................. 30

5.4.3 Acute Dietary Risk Assessment............................................................................... 30

5.4.4 Chronic Dietary Risk Assessments ......................................................................... 30

5.4.5 Summary Table......................................................................................................... 31

6.0 Residential (Non-Occupational) Exposure/Risk Characterization ............................. 31

6.1 Residential Handler Exposure .................................................................................... 31

6.2 Post-Application Exposure.......................................................................................... 34

6.3 Combined Residential Risk Estimates (Multiple Exposure Scenarios)................... 34

6.4 Residential Risk Estimates for Use in Aggregate Assessment.................................. 35

6.5 Residential Bystander Post-application Inhalation Exposure ................................. 35
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6.6 Spray Drift.................................................................................................................... 35

7.0 Aggregate Exposure/Risk Characterization.................................................................. 36

7.1 Acute Aggregate Risk................................................................................................... 36

7.2 Short-Term Aggregate Risk........................................................................................ 36

7.3 Chronic Aggregate Risk .............................................................................................. 37

8.0 Cumulative Exposure/Risk Characterization ............................................................... 37

9.0 Occupational Exposure/Risk Characterization ............................................................ 37

9.1 Short-/Intermediate-Term Handler Risk................................................................... 38

9.2 Short-and Intermediate-Term Post-Application Risk.............................................. 39

9.2.1 Dermal Post-Application Risk................................................................................. 39

9.2.2 Inhalation Post-Application Risk............................................................................ 39

10.0 References......................................................................................................................... 40

Appendix A. Toxicology Profile and Executive Summaries .................................................. 41

A.1 Toxicology Data Requirements................................................................................... 41

A.2 Toxicity Profiles............................................................................................................ 42

Appendix B. Physicochemical Properties of Boscalid. ........................................................... 47

Appendix C. Review of Human Research................................................................................ 47

Appendix D. Summaries of Field Residue Data...................................................................... 48

Appendix E. Summaries of Occupational Handler and Post-application Exposure and Risk 

Estimates...................................................................................................................................... 49

Appendix F. International Residue Limits Status Sheet........................................................ 52
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1.0 Executive Summary

Introduction

Boscalid, 3-pyridinecarboxamide, 2-chloro-N-(4'-chloro[1,1'-biphenyl]-2-yl), is a fungicide 

active ingredient that works inside the mitochondria of fungi and stops fungi from producing the 

energy that they need to carry on basic functions. Boscalid prevents energy production by

binding to the enzyme succinate ubiquinone reductase. Boscalid is currently registered on 

numerous agricultural crops and on golf course turf.

Use Profile

The proposed actions of boscalid are as follows: 1) The Interregional Research Project No. 4 (IR4) is proposing new agricultural uses (PP# 2F8069) on artichoke, Belgium endive, and 

persimmon; 2) BASF is proposing a new greenhouse tomato use for commercial production and 

for tomato transplants grown for the home consumer market; 3) Bonide Products is proposing a 

new use on residential fruit and nut trees; and 4) BASF is proposing new uses on residential 

ornamentals and landscape gardens. Additionally, crop group expansions/revisions were 

requested for the bulb vegetable group 3-07, fruiting vegetable 8-10, citrus fruit group 10-10, 

pome fruit group 11-10, berry subgroups 13-07A, B, F, and G, vegetable root subgroup 1B 

except sugar beet, and oilseed group 20.

The proposed agricultural labels require occupational handlers to wear the following personal 

protective equipment (PPE): long-sleeved shirts, long pants, chemical resistant gloves, and 

coveralls in a few cases. The 12 hour restricted entry interval (REI) listed on the labels is 

appropriate. 

Exposure Profile

The proposed residential uses result in short-term handler dermal and inhalation exposures for 

adults, short-term post-application dermal exposures for adults, youths (11 to 16 years old), and 

children 6 to 11 years old, and short-term post-application dermal and incidental oral exposures 

for children (1 to <2 years old). Exposure pathways include dietary (food and drinking water), 

and residential exposure sources. Dietary exposures are also expected for acute and chronic 

durations. Occupational exposures are expected via dermal and inhalation routes for short- and 

intermediate-term durations.

Hazard Assessment 

In subchronic and chronic feeding studies in rats, mice and dogs, boscalid generally caused 

decreased body weights and body weight gains and effects on the liver as well as on the thyroid. 

While the dog appeared to be the most sensitive species in the subchronic studies, the sensitivity

of the dog and the rat was similar in the chronic studies. Based on weak evidence of carcinogenic 

effects in male rats, boscalid is classified as, “suggestive evidence of carcinogenicity, but not 

sufficient to assess human carcinogenic potential.” Boscalid was negative in the mutagenicity

battery, the neurotoxicity battery and the immunotoxicity study. There were no susceptibility

concerns and no residual uncertainties regarding developing offspring, and the FQPA Safety

Factor was reduced to 1X in the risk assessment. Boscalid has low acute toxicity via the oral, 

dermal, and inhalation routes of exposure and is not a dermal sensitizer, primary eye irritant, or 

skin irritant. Endpoints and points of departure were selected for chronic dietary, incidental oral 
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(short- and intermediate-term), dermal (all durations) and inhalation (all durations) exposure 

scenarios. As there were no toxic effects attributable to a single dose, an endpoint for acute 

dietary was not identified. The level of concern (LOC) for all exposure scenarios is a margin of 

exposure (MOE) <100, with the exception of inhalation exposures where the LOC is an MOE of 

<1000 because a subchronic inhalation study is required for this risk assessment but is not 

available.

Dietary Exposure

The residue chemistry and environmental fate data are adequate to assess human dietary

exposure. The assessments are based on reliable data and will not underestimate exposure or 

risk. Estimated drinking water concentrations (EDWCs) were incorporated directly into the 

dietary exposure assessments. 

Since no observed effects could be attributed to a single dose, an acute endpoint was not 

established. Therefore, an acute dietary exposure assessment was not conducted.

The results of the slightly refined chronic dietary (food and drinking water) analysis are below 

the Agency’s level of concern for all population subgroups. The dietary exposure for food and 

drinking water for the general U.S. population is 20% of the chronic Population Adjusted Dose 

(cPAD) and 56% of the cPAD for children 1-2 years old, the population subgroup with the 

highest estimated chronic dietary exposure to boscalid.

Residential Exposure

New residential uses were requested in this action. Additionally, boscalid is currently registered 

for use on golf course turf. Residential exposures from the proposed and existing residential uses

were assessed using the updated 2012 HED Residential Standard Operating Procedures1(SOPs). 

Residential exposure is expected to be short-term only. Because the dermal and inhalation PODs 

are the same, the dermal and inhalation handler exposure estimates were combined using the 

aggregated risk index (ARI) approach. All residential handler dermal and inhalation exposure 

risk estimates were not of concern to HED, with ARI values ranging from 24 to 330. All 

residential post-application dermal exposure risk estimates were also not of concern to HED, 

with margins of exposure (MOEs) ranging from 690 to 16,000. 

Aggregate Exposure

There is potential for short-term and chronic exposure to boscalid via dietary (which is 

considered background exposure) and residential (which is considered primary) exposure 

pathways. The aggregate MOEs are 310 for children 6 to 11 years old, 690 for youths 11 to 16 

years old, and 290 for adults. None of these aggregate risk estimates are of concern to HED.

Occupational Exposure

Based on the proposed agricultural uses, there is potential for short- and intermediate-term 

occupational exposure during mixing, loading, and other handling tasks; and during postapplication activities. The proposed labels require occupational handlers to wear the following 

personal protective equipment (PPE): long-sleeved shirts, long pants, and chemical resistant 

 

1

http://www.epa.gov/pesticides/science/residential-exposure-sop.html
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gloves. Because the dermal and inhalation PODs are the same, the dermal and inhalation handler 

exposure estimates were combined using the ARI approach. 

All of the occupational handler ARIs are greater than 1.0 when assessed using labeled PPE 

(gloves), and are not a concern to HED.

All post-application scenarios resulted in dermal exposure MOEs greater than 100 on day 0 (12 

hours after application), and therefore, are not of concern to HED. The MOEs for boscalid 

ranged from 400 to 21,000. Dislodgable foliar residue (DFR) studies are not required at this time 

for boscalid since the lowest dermal MOE (400) is greater than 4 times the LOC based on default 

input values.

Based on the Agency's current practices, a quantitative non-cancer occupational post-application 

inhalation exposure assessment was not performed for boscalid at this time. If new policies or 

procedures are put into place, the Agency may revisit the need for a quantitative occupational 

post-application inhalation exposure assessment for boscalid. The 12 hour restricted entry

interval (REI) listed on the labels is appropriate. 

Review of Human Research

This risk assessment relies in part on data from studies in which adult human subjects were 

intentionally exposed to a pesticide or other chemical. These data, which include studies from 

the Pesticide Handlers Exposure Database, Version 1.1 (PHED 1.1), the Agricultural Handler 

Exposure Task Force (AHETF) database, the Residential SOPs (lawns and turf), and MRID 

45773201 are subject to ethics review pursuant to 40 CFR 26, have received that review, and are 

compliant with applicable ethics requirements. For certain studies that 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 http://www.epa.gov/pesticides/science/handler-exposuredata.html and http://www.epa.gov/pesticides/science/post-app-exposure-data.html. 

Environmental Justice Considerations

Potential areas of environmental justice concerns, to the extent possible, were considered in this 

human health risk assessment, in accordance with U.S. Executive Order 12898, "Federal Actions 

to Address Environmental Justice in Minority Populations and Low-Income Populations," 

(http://www.eh.doe.gov/oepa/guidance/justice/eo12898.pdf. 

2.0 HED Recommendations

HED has examined the toxicology and residue chemistry databases for boscalid. Pending 

submission of revised Sections B and F, there are no toxicology or residue chemistry issues that 

would preclude granting Section 3 registration for the requested uses of boscalid, or 

establishment of tolerances for residues of boscalid. Additional data are needed, as outlined 

below in Section 2.1. The specific tolerance recommendations are discussed in Section 2.2, and 

label modifications are discussed in Section 2.3.
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2.1 Data Deficiencies

870.3465 Subchronic Inhalation study

 A subchronic Inhalation study is required because the use of an oral point of departure 

(POD) for inhalation exposure results in MOEs as low as 370 for occupational exposure, 

which is not sufficient to alleviate concern (TXR0056585. K. Rury. 03/04/2013). 

Therefore, a 10X database uncertainty factor has been added for inhalation exposures.

2.2 Tolerance Considerations

2.2.1 Enforcement Analytical Method

There are adequate residue analytical methods for tolerance enforcement and data collection.

An adequate gas chromatography/mass spectrometry (GC/MS) method (Method D0008) is 

available for enforcing boscalid tolerances in plant commodities. The Analytical Chemistry

branch/Biological and Economic Analysis Division (ACB/BEAD) concluded that the method is 

acceptable for enforcement purposes in plants without the need for an EPA validation 

(DP284510; D. Swineford and E. Kolbe, 8/12/2003, PMV memo).

An enforcement method is available for determining the residues of concern in livestock. 

Method DFG S19 is a GC/electron capture detection method that was successfully validated by

ACB/BEAD. For the most recent livestock feeding study, residues of boscalid and its hydroxy 

metabolite M510F01 (including the glucuronide conjugate M510F02) were determined using a 

LC/MS/MS method (BASF Method 471/0, modified) which was previously reviewed in 

conjunction with earlier feeding studies.

Residues of boscalid and its metabolite M510F01 were not adequately recovered using the 

multiresidue methods. Protocol A was not applicable. Protocol B was not applicable for 

boscalid and yielded inconsistent recoveries of M510F01. Residues of boscalid and its hydroxy 

metabolite M510F01 had good responses with GC/ECD on a DB-1 column under Protocol C. 

Neither analyte was recovered at ≥30% using Protocols D, E, and F. The study has been 

forwarded to FDA for a future updating of PAM, Vol. I.

2.2.2 Recommended Tolerances

For the use of boscalid on globe artichoke, Belgium endive, and persimmon, tolerances are 

required. Based on evaluation of the field trial data with the Organization of Economic 

Cooperation and Development (OECD) tolerance calculation procedure (Appendix II), the 

tolerances listed in Table 2.2.2.1 are appropriate. With the establishment of the tolerance for 

Belgium endive, the existing tolerance for Section 18 emergency exemption for Belgium endive 

should be removed.
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Several crop group conversions were requested. Most were crop group or subgroup updates.

The request to replace vegetable, root subgroup 1A, except sugar beet, garden beet, radish, and 

turnip at 1.0 ppm with vegetable, root, except sugar beet, subgroup 1B at 1.0 ppm is not 

acceptable. The original tolerance was established based on data for carrot only (DP287829, M. 

Nelson, MRID 45405113). No field trial data were submitted for radish, the other representative 

commodity. Therefore the request must be amended to vegetable, root, except sugar beet, 

subgroup 1B, except garden beet, radish, and turnip at 1.0 ppm. The proposed changes and their 

evaluation are summarized in Table 2.2.2.1.

Table 2.2.2.1. Tolerance Summary for Boscalid.

Commodity Proposed/Existing

Tolerance (ppm)

Recommended/ 

Harmonized

Tolerance (ppm)

Comments; Correct Commodity 

Definition

40 CFR 180.589(a) General. It is recommended that tolerances be established for residues of the fungicide 

boscalid, including its metabolites and degradates, in or on the commodities listed below. Compliance with the 

tolerance levels specified below is to be determined by measuring only boscalid, 3-pyridinecarboxamide, 2-

chloro- N -(4′-chloro[1,1'-biphenyl]-2-yl), in or on the following raw agricultural commodities:

Artichoke, globe 6.0 6.0

Endive, belgium 5.0 6.0 OECD statistical calculation 

estimates 6.0 ppm

Persimmon 7.0 8.0 OECD statistical calculation 

estimates 8.0 ppm 

Vegetable, bulb, group 3-07 3.0 5.0 Group update. Harmonization 

with Codex (VA 0035 Bulb 

vegetables: 5 mg/kg)

Vegetable, bulb, group 3 3.0 Remove Group update.

Vegetable, fruiting, group 8-10 1.2 3.0 Group update. Harmonization 

with Codex (Fruiting vegetables 

other than cucurbits VO 0050: 3 

mg/kg)

Vegetable, fruiting, group 8 1.2 Remove Group update.

Fruit, citrus, group 10-10 1.6 2.0 Group update. Harmonization 

with Codex (Citrus fruits FC 

0001: 2 mg/kg)

Fruit, citrus, group 10 1.6 Remove Group update.

Fruit, pome, group 11-10 3.0 3.0 Group update.

Fruit, pome, group 11 3.0 Remove Group update.

Caneberry subgroup 13-07A 6.0 10.0 Subgroup update. 

Harmonization with Codex 

(Berries and other small fruits, 

FB 0018: 10 mg/kg)

Caneberry subgroup 13A 6.0 Remove Subgroup update.

Bushberry subgroup 13-07B 13.0 13.0 Subgroup update.

Bushberry subgroup 13B 13.0 Remove Subgroup update.

Fruit, small, vine climbing, 

except fuzzy kiwifruit, 

subgroup 13-07F

3.5 5.0 Subgroup update. 

Harmonization with Codex 

(Grapes FB 0269: 5 mg/kg)
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Table 2.2.2.1. Tolerance Summary for Boscalid.

Commodity Proposed/Existing

Tolerance (ppm)

Recommended/ 

Harmonized

Tolerance (ppm)

Comments; Correct Commodity 

Definition

Grape 3.5 Remove Group update. See subgroup 13-

07F.

Berry, low growing, subgroup 

13-07G except cranberry

4.5 4.5 Subgroup update.

Strawberry 4.5 Remove Group update. See subgroup 13-

07G.

Oilseed group 20 3.5 5.0 Group update. Harmonization 

with Canada (canola oil and 

mustard seed oil, 5.0 ppm)

Canola, seed 3.5 Remove Group update. See group 20.

Sunflower, seed 0.60 Remove Group update. See group 20.

Cotton, undelinted seed 1.0 Remove Group update. See group 20.

Vegetable, root, except sugar

beet, subgroup 1B

1.0 2.0 Vegetable, root, except sugar

beet, subgroup 1B, except 

garden beet, radish, and turnip.

Subgroup update. 

Harmonization with Codex 

(Root and tuber vegetables, VR 

0075: 2 mg/kg)

Vegetable, root subgroup 1A, 

except sugar beet, garden beet, 

radish, and turnip

1.0 Remove Group update.

Turnip, greens 18.0 40.0 Turnip, greens

Translation of data from mustard 

greens, for which a tolerance of 

18.0 ppm exists (Brassica leafy 

greens). Harmonization with 

Codex (Leafy vegetables VL 

0053: 40 mg/kg)

40 CFR 180.589(b) Section 18 emergency exemptions 

Endive, belgium 16 Remove Replaced by tolerance under 40 

CFR 180.589(a)

40 CFR 180.589(d) Indirect or inadvertent residues

Flax, seed 3.5 Remove Group update. See group 20.

Cotton, gin byproducts 0.30 Remove Duplicate of existing 40 CFR 

180.589(a) entry.

No new tolerances are proposed for boscalid based on the proposed residential use on pome fruit, 

stone fruit, and tree nuts using the proposed label for the Bonide Products, Inc FT09 (EPA File 

Symbol 4-UII). The existing tolerances based on the BASF Pristine®label cover these

residential uses on pome fruit, stone fruit, and tree nuts. The Bonide Products, Inc FT09 label 

compares favorably with the BASF Pristine®label. Therefore, the existing tolerances for pome 

fruit, stone fruit, and tree nuts will also cover the proposed new residential uses.
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2.2.3 Revisions to Petitioned-For Tolerances

860.1550 Proposed Tolerances

 The available data for Belgium endive will not support a tolerance level of 5.0 ppm. A 

revised Section F should be submitted with a tolerance for Belgium endive at 6.0 ppm.

 The available data for persimmon will not support a tolerance level of 7.0 ppm. A 

revised Section F should be submitted with a tolerance for persimmon at 8.0 ppm.

Several crop group conversions were requested. Most were crop group or subgroup updates. 

The request to replace vegetable, root subgroup 1A, except sugar beet, garden beet, radish, and 

turnip at 1.0 ppm with vegetable, root, except sugar beet, subgroup 1B at 1.0 ppm is not 

acceptable. The original tolerance was established based on data for carrot only (D287829, M. 

Nelson, MRID 45405113). No field trial data were submitted for radish, the other representative 

commodity. Therefore the request must be amended to vegetable, root, except sugar beet, 

subgroup 1B, except garden beet, radish, and turnip. Moreover, the tolerance should be revised 

to 2.0 ppm in order to harmonize with Codex. 

The request to create a tolerance for turnip greens is acceptable. Turnip greens may be covered 

by translation of field trial residue data for mustard greens. Data for the latter were used in 

establishing the Brassica leafy greens subgroup 5B tolerance at 18.0 ppm. However, the 

proposed value of 18 ppm is not acceptable. A value of 40.0 ppm is recommended in order to 

harmonize with Codex. 

The proposed conversions of certain existing crop groups (including the removal of certain 

commodity or commodity group/subgroup tolerances), with the exception of the conversion of 

vegetable, root, subgroup 1A except sugar beet, garden beet, radish, and turnip at 1.0 ppm to 

vegetable, root subgroup 1B, except sugar beet, at 1.0 ppm are acceptable. The exceptions of 

garden beet, radish, and turnip must be maintained.

2.2.4 International Harmonization

Codex MRLs and/or Canadian MRLs have not been established for boscalid in/on globe 

artichoke, Belgium endive, or persimmon. Therefore, there is no issue of harmonization with 

Codex or Canada for these commodities (see Appendix F).

Some harmonizations with Codex were not possible because the corresponding commodity

group/subgroup tolerance in the US is higher than the Codex MRL. Decreasing the tolerance 

value has the potential to create apparent violation of the label use instructions when boscalid is 

used according to the label. Subgroup 13.07G could not be changed from 4.5 ppm to harmonize 

with Codex (strawberry, 3 mg/kg). Pome fruit group 11-10 could not be changed from 3.0 to 

harmonize with Codex (apple, 2 mg/kg). Bushberry subgroup 13-07B could not be changed 

from 13.0 ppm to harmonize with Codex (small berry, 10 mg/kg).
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Many of the group crop updates include changes in the tolerances in order to harmonize with 

Codex. These are bulb vegetable group 3-07 (3.0 to 5.0 ppm); fruiting vegetables group 8-10 

(1.2 to 3.0 ppm); citrus fruit group 8-10 (1.6 to 2.0 ppm); caneberry subgroup 13-07A (6.0 to 

10.0 ppm); small vine fruit subgroup 13-07F (3.5 to 5.0 ppm); root vegetable subgroup 1B (1.0 

to 2.0 ppm). The update from canola, sunflower, and cotton seeds to oilseed group 20 includes a 

revision in the tolerance from 3.5 ppm to 5.0 ppm in order to harmonize with Canada.

Also, the proposed turnip greens tolerance (18 ppm) is based on the proposed addition of turnip 

greens (turnip tops) to crop subgroup 5B, for which adequate data were previously presented for 

the representative commodity mustard greens. The tolerance proposal of 18.0 ppm is changed to 

40.0 ppm in order to harmonize with Codex.

2.3 Label Recommendations

860.1200 Directions for Use

 The proposed Pristine®label (EPA Reg. No. 7969-199) and the proposed Endura®label 

(EPA Reg. No. 7969-197) provide directions for use on “root vegetables, 1B (except 

sugar beet).” This must be modified to use on “vegetable, root, except sugar beet, 

subgroup 1B, except garden beet, radish, and turnip”. The specific crops garden beet, 

radish, and turnip must be removed from the description of root vegetables for treatment 

with Pristine®.

 The proposed Pristine® label (Reg. No. 7969-199) and the proposed Endura ® label 

(EPA Reg. No. 7969-197) provide directions for use on the low growing berry subgroup

13-07G. Cranberry must be removed from the list of crops. The title “low growing berry

subgroup” should be changed to “berry, low growing, subgroup 13-07G, except 

cranberry.”

3.0 Introduction

Boscalid, 3-pyridinecarboxamide, 2-chloro-N-(4'-chloro[1,1'-biphenyl]-2-yl), is a fungicide 

active ingredient that works inside the mitochondria of fungi and stops fungi from producing the 

energy that they need to carry on the basic functions in life like obtaining food, growing and

reproducing. Boscalid prevents energy production by binding to the enzyme succinate 

ubiquinone reductase. 

Boscalid is currently registered on alfalfa, beans, berries, Brassica vegetables (subgroups 5A and 

5B), bulb vegetables, canola, carrots, celery, certain root vegetables, citrus, cotton, cucurbit 

vegetables, edible peas, fruiting vegetables, herbs (herbs subgroup 19A), grapes, lettuce, Leafy

Greens Subgroup 4A, except head and leaf lettuce, and leaf petioles subgroup 4B, mint, peanuts, 

pistachios, pome fruits, potatoes, soybeans, spinach, stone fruits, strawberries, tree nuts, tropical 

fruits (avocado, black sapote, canistel, mamey sapote, mango, papaya, sapodilla, and star apple) 

sunflower, seed treatment of rapeseed, greenhouse grown tomatoes, imported bananas, and 

imported coffee, as well as golf course turf.
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The proposed actions of boscalid are as follows: 1) The Interregional Research Project No. 4 (IR4) is proposing new agricultural uses (PP# 2F8069) on artichoke, Belgium endive, and 

persimmon; 2) BASF is proposing a new greenhouse tomato use for commercial production and 

for tomato transplants grown for the home consumer market; 3) Bonide Products is proposing a 

new use on residential fruit and nut trees; and 4) BASF is proposing new uses on residential 

ornamentals and landscape gardens. Additionally, crop group expansions/revisions were 

requested for the bulb vegetable group 3-07, fruiting vegetable 8-10, citrus fruit group 10-10, 

pome fruit group 11-10, berry subgroups 13-07A, B, F, and G, vegetable root subgroup 1B 

except sugar beet, and oilseed group 20.

3.1 Chemical Identity

The chemical structure and nomenclature of boscalid and its hydroxyl metabolite are presented 

in Tables 3.1.

Table 3.1. Nomenclature of Boscalid and its Hydroxy Metabolite.

Compound

Common name Boscalid; Nicobifen

Company experimental name BAS 510 F

IUPAC name 2-chloro-N-(4׳-chlorobiphenyl-2-yl)nicotinamide

CAS name 2-chloro-N-(4'-chloro[1,1'-biphenyl]-2-yl)-3-pyridinecarboxamide

Molecular weight 343.2

CAS registry number 188425-85-6

End-use product (EPs) 25.2% WDG (Pristine®Fungicide; EPA Reg. No. 7969-199, also contains 12.8% 

pyraclostrobin)

70% WDG (Endura®Fungicide; EPA Reg. No. 7969-197)

Hydroxy-metabolite

Common name Boscalid hydroxy metabolite

Company experimental name M510F01 (glucuronide conjugate – M510F02)

CAS name 2-chloro-N-(4'-chloro-5-hydroxy-biphenyl-2-yl)nicotinamide

Molecular weight 359.2

N

N

O

Cl

Cl

N

N

O

Cl

Cl

OH
Page 14 of 53

3.2 Physical/Chemical Characteristics

If released to air, a vapor pressure of 5.4 x 10-9 mm Hg at 20o C indicates boscalid will exist 

solely in the particulate phase in the atmosphere. Particulate-phase boscalid will be removed 

from the atmosphere by wet or dry deposition. Boscalid will not volatilize from dry soil surfaces 

based upon its vapor pressure. Boscalid is stable to direct photolysis by sunlight. If released to 

soil, boscalid is expected to have low mobility based upon an estimated Koc of 970. 

Volatilization from moist soil surfaces or water surfaces is not expected to be an important fate 

process based upon a Henry's Law constant of 5.1 x 10-10 atm-cu m/mole. A biodegradation 

half-life in soil ranging from 96 to 578 days and a dissipation half-life range of 27 to 372 days 

indicate that biodegradation is not an important environmental fate process. If released into 

water, boscalid is expected to adsorb to suspended solids and sediment based upon the estimated 

Koc. An estimated bioconcentration factor (BCF) of 38 suggests the potential for 

bioconcentration in aquatic organisms is moderate. Boscalid is stable to hydrolysis. The 

physiochemical properties of boscalid are summarized in Appendix B. 

3.3 Pesticide Use Pattern

Globe artichoke, Belgium endive, and persimmon

IR-4 is proposing the use of Pristine Fungicide on globe artichokes, Belgium endive, and 

persimmons. Pristine Fungicide (EPA Reg. No. 7969-199) is a MAI WDG fungicide containing 

12.8% pyraclostrobin and 25.2% boscalid. Belgium endive may be treated at a maximum rate of 

0.025 lb ai/1000 lb roots prior to cold storage and 0.028 lb ai/70 ft2prior to forcing, each at one 

application per season. The maximum single application rate for artichoke and persimmon is 

0.36 lb ai/A using aerial, ground, or chemigation equipment. Pristine may be applied 3 times per 

crop cycle at a maximum crop-cycle application rate of 1.08 lb ai/A/yr. 

Greenhouse tomato use for commercial production and for tomato transplants grown for the 

home consumer market

BASF is proposing the use of Pagent® Fungicide on greenhouse grown tomatoes. Pagent® 

Fungicide label (EPA Reg. No.7969-251) is a MAI WDG fungicide containing 12.8% 

pyraclostrobin and 25.2% boscalid. Pagent may be applied at a maximum single application rate 

of 0.36 lb ai/A (or 0.0036 lb ai/gal). Pagent may be applied 3 times per crop cycle at a maximum 

crop-cycle application rate of 1.08 lb ai/A (or 0.0108 lb ai/gal). Handlers may apply Pagent 

using high or low pressure sprayer, or a backpack sprayer. 

Residential fruit and nut trees

Bonide Products is proposing a new product, Bonide® Fruit Tree Spray Concentrate (FT09), for 

use on home orchard fruit and nut trees via a homeowner applicator. Bonide® Fruit Tree Spray

Concentrate (EPA Reg No.4-UII) is a MAI SC fungicide containing 0.500% lambda-cyhalothrin, 

3.06% pyraclostrobin, and 5.622% boscalid. The maximum single application rate is 0.22 lb 

ai/A with no more than 4 or 5 applications per year, depending on the tree type. The retreatment 

interval ranges from 7 to 10 days. Residential handlers may apply FT 09 using handheld spray 

equipment.
Page 15 of 53

Residential ornamentals and landscape gardens

BASF is proposing a new product, Homeowner Garden Spray Fungicide, for use on residential 

ornamentals and landscape gardens via a residential applicator. Homeowner Garden Spray

Fungicide (EPA Reg No. 7969-GLG) is a MAI SC fungicide containing 9.0% pyraclostrobin and 

18.0% boscalid. The maximum single application rate for this product is 0.0033 lb ai/gal via 

residential handheld spray equipment or hose-end sprayers.

The proposed uses of boscalid are summarized in Table 3.3.

Table 3.3. Use Profile for Proposed Boscalid Uses

Proposed

Use

Product 

Formulation

[EPA Reg. No.]

Application 

Equipment

Max. Single 

Applic. Rate 

(lb ai/A)

Max. No. 

Applic. 

Per 

Season

Max. 

Seasonal 

Applic. 

Rate 

(lb 

ai/A/yr)

PHI 

(days)

Use Directions and 

Limitations

Globe 

Artichoke

Persimmon

Pristine Fungicide 

[EPA Reg. No.7969-

199]

WDG 25.2% boscalid

Ground, 

Aerial, or 

Chemigation

0.36 3 1.1 0

Continue treatment on a 7 to 

14 day interval.

Belgium 

endive

Make one app 

as a spray to 

roots when 

brought into 

cold storage 

prior to 

forcing. 

Apply again 

at the 

beginning of 

forcing after 

the roots have 

been packed 

in forcing 

trays.

Prior to cold 

storage:

0.028 lb ai/1000 lb 

roots

1

NA 19

Prior to Cold Storage: make 

one app as a spray to the 

roots as they move along a 

conveyor belt used to bring 

the roots from field 

transportation into cold 

storage bins.

Prior to forcing: 

0.028 lb ai/70ft2of 

forcing tray

1

Prior to Forcing: make one 

app as a spray to roots at the 

beginning of forcing, after 

they have been packed into 

forcing trays.

Greenhouse 

tomatoes

Pagent® Fungicide

[EPA Reg. No.7969-

251]

WDG 25.2% boscalid

Chemigation,

Ground, or

Handheld 

spray 

equipment

0.36 lb ai/A

or

0.0036 lb ai/gal 

3

1.1 0

For commercial production:

Apply as a foliar spray in a 

minimum of 100 gal/A 

water volume. 

Allow at least 7 days 

between applications.

Do not make more than one 

application before 

alternations to a fungicide 

with a different mode of 

action for at least on 

application.

0.28 lb ai/A

or

0.0028 lb ai/gal 

0.85 NA

For tomato transplants 

grown for the home 

consumer market:

Do not exceed 100 gal/A 

spray volume.

Allow at least 7 days 

between applications.

Do not use in transplant 

production for commercial 

field-grown tomatoes.
Page 16 of 53

Table 3.3. Use Profile for Proposed Boscalid Uses

Proposed

Use

Product 

Formulation

[EPA Reg. No.]

Application 

Equipment

Max. Single 

Applic. Rate 

(lb ai/A)

Max. No. 

Applic. 

Per 

Season

Max. 

Seasonal 

Applic. 

Rate 

(lb 

ai/A/yr)

PHI 

(days)

Use Directions and 

Limitations

Do not apply more than 2 

consecutive applications in 

any crop production cycle.

Residential 

fruit and nut 

trees

Bonide® Fruit Tree 

Spray Concentrate 

(FT09)

[EPA Reg. No. 4-UII]

SC 5.62% boscalid

Handheld 

spray 

equipment

0.0076 lb ai/gal

0.000051 lb ai/ft2

0.22 lb ai/A

Pome 

Fruit and 

Tree 

nuts: 4

Stone 

Fruit: 5

Pome 

Fuit: 21

Stone 

Fruit: 14

Almonds: 

25

Tree 

Nuts: 14

Apply thoroughly as a foliar 

cover spray to both sides of 

plant leaves and surfaces. 

Spray leaf surfaces to the 

point of drip but do not 

exceed 2 fl oz of product per 

1,500 ft2

Residential 

ornamentals

Homeowner Garden 

Spray Fungicide 

[EPA Reg. No. 7969-

GLG]

SC 18.0% boscalid

Handheld 

spray 

equipment

0.0033 lb ai/gal

0.33 lb ai/A1

6 NA

For manual spray 

applications: spray until 

foliage is wet.

For hose-end sprayers: 

typically hose-end 

applicators are designed to 

deliver the desired dial 

setting per gallon of water in 

30 seconds.

Retreatment interval is 14 

days.

1 Assumed 100 gallons treats 1 acre based on other similar labels; HED recommends that the Homeowner Garden Spray Fungicide (EPA Reg.

No. 7969-GLG) label should be clarified by including the spray volume (i.e., number of gallons of spray treated per acre). This information is 

needed so that the application rate can be presented in terms of lbs ai/A as well as, lbs ai/gal (which is currently on the label). 

3.4 Anticipated Exposure Pathways

The Registration Division has requested an assessment of human health risk to support proposed 

new uses of boscalid on the following: 1) agricultural crops globe artichoke, Belgium endive, 

and persimmon; 2) greenhouse tomato use for commercial production and for tomato transplants 

grown for the home consumer market; 3) residential fruit and nut trees; and 4) residential 

ornamentals and landscape gardens. Humans may be exposed to boscalid in food and drinking 

water, since boscalid may be applied directly to growing crops and application may result in 

boscalid reaching surface and ground water drinking water sources. There are residential uses of 

boscalid so there is exposure to residential handlers and those entering treated areas following 

application. In occupational settings, applicators may be exposed while handling boscalid. 

There is a potential for post-application exposure for workers re-entering treated fields and 

residents re-entering treated areas. 
Page 17 of 53

Risk assessments have been completed for proposed and existing uses of boscalid. This risk 

assessment considers all of the aforementioned exposure pathways based on the proposed new 

uses of boscalid, but also considers existing uses of boscalid, particularly in the dietary and 

residential exposure assessments. 

3.5 Consideration of Environmental Justice

Potential areas of environmental justice concerns, to the extent possible, were considered in this 

human health risk assessment, in accordance with U.S. Executive Order 12898, "Federal Actions 

to Address Environmental Justice in Minority Populations and Low-Income Populations," 

(http://www.eh.doe.gov/oepa/guidance/justice/eo12898.pdf. As a part of every pesticide risk 

assessment, OPP considers a large variety of consumer subgroups according to well-established 

procedures. In line with OPP policy, HED estimates risks to population subgroups from 

pesticide exposures that are based on patterns of that subgroup’s food and water consumption, 

and activities in and around the home that involve pesticide use in a residential setting. 

Extensive data on food consumption patterns are compiled by the U.S. Department of 

Agriculture’s National Health and Nutrition Examination Survey, What We Eat in America, 

(NHANES/WWEIA) and are used in pesticide risk assessments for all registered food uses of a 

pesticide. These data are analyzed and categorized by subgroups based on age and ethnic group. 

Additionally, OPP is able to assess dietary exposure to smaller, specialized subgroups and 

exposure assessments are performed when conditions or circumstances warrant. Whenever 

appropriate, non-dietary exposures based on home use of pesticide products and associated risks 

for adult applicators and for toddlers, youths, and adults entering or playing on treated areas 

post-application are evaluated. Further considerations are currently in development as OPP has 

committed resources and expertise to the development of specialized software and models that 

consider exposure to bystanders and farm workers as well as lifestyle and traditional dietary

patterns among specific subgroups.

4.0 Hazard Characterization and Dose-Response Assessment

4.1 Toxicology Studies Available for Analysis

The available toxicity database includes: 

 acute toxicity battery,

 oral subchronic studies (rat, mouse and dog),

 dermal subchronic study (rat),

 oral developmental (rat, rabbit), reproductive (rat), neurotoxicity (rat, acute and 

subchronic) and immunotoxicity (rat) studies,

 oral chronic (rat, dog) and carcinogenicity (rat, mouse) studies,

 mutagenicity battery,

 metabolism and pharmacokinetics studies (rat), and

 special oral subchronic (rat) studies on hepatic enzyme induction, thyroid hormone 

induction and reversibility of these inductions.
Page 18 of 53

Anticipated exposure routes include oral, dermal and inhalation. While acute and subchronic 

oral and dermal studies are available, a subchronic inhalation study was not included in the 

submitted toxicity database.

4.2 Absorption, Distribution, Metabolism and Excretion (ADME)

In metabolism and kinetics studies, boscalid was absorbed to some degree, 17% in the low dose 

(50 mg/kg/day) and 3.5% at 500 mg/kg/day. These values were increased approximately threefold when biliary excretion data were incorporated. The lower percentages of high-dose 

absorption were considered to be due to saturation, which was supported by the decreased 

urinary and biliary excretion, and greater fecal excretion observed in the high-dose group. There 

did not appear to be any biologically relevant differences in the total absorption between the 

single dose and the 15-day repeated dose regimens nor were there any remarkable gender-related 

differences. Maximum plasma concentration (Tmax) was achieved in 8 hours regardless of dose. 

Elimination of radioactivity from the plasma appeared to be biphasic with a rapid decline from 

Tmax to 24 hours (t1/2~8.1 hr) followed by a slower elimination phase (t1/2~29.9 hr). There did not 

appear to be biologically significant gender-related differences in pharmacokinetic parameters. 

The AUC values and maximum plasma concentrations did not reflect the 10-fold difference in 

administered dose.

Tissue distribution data showed that radioactivity was most prevalent in organs/tissues associated 

with absorption, metabolism and elimination processes such as liver, kidneys, gut, and adipose 

tissue. Tissue burdens for the low- and high-dose groups did not, however, reflect the 10-fold 

difference in dose. Radioactivity in the thyroid and bone marrow appeared to be greatest at the 

168–hour time point. The metabolite characterization findings were consistent with Phase I

oxidation followed by Phase II conjugation processes. The most prominent metabolites in the 

urine, bile, and liver were M510F01 (a hydroxylation product) and M510F02 (a glucuronide 

conjugate). In the feces, parent compound (representing unabsorbed material) was the most 

prevalent component.

Excretion of administered radioactivity was primarily via the feces (~80-98%) for all treatment 

groups regardless of dose level or label position. Urinary excretion accounted for the majority of 

the remainder of the radiolabel. Although excretion profiles were similar for the single highdose and repeat high-dose groups, somewhat greater urinary excretion of radioactivity was 

observed for the low-dose group. Biliary excretion represented approximately 40 to 50% of the 

fecal radioactivity in the low-dose group but only about 10% in high-dose group. This was also 

confirmed by the plasma kinetics and AUC data. Excretory patterns did not significantly differ 

by gender or position of the radiolabel.

4.2.1 Dermal Absorption

Based on the results of an available dermal absorption study in rats, the dermal absorption factor 

(DAF) of boscalid was determined to be 15% in the previous risk assessment, as represented by 

11% being absorbed plus 4% found as bound residue on the skin following a 24 hr exposure and 

24 hr sacrifice. The 10 hr exposure and 10 hr sacrifice DAF is 11%, based on 8% being 

absorbed and 3% found as bound residue on the skin.
Page 19 of 53

4.3 Summary of Toxicological Effects

Boscalid is a carboxamide (anilide) fungicide that acts in the fungal cell by inhibiting 

mitochondrial respiration and subsequent production of adenosine triphosphate (ATP) and by

inhibiting the succinate-ubiquinone oxidase reductase system in Complex II of the mitochondrial 

electron transport chain.

In mammals, the primary targets are the liver and the thyroid (indirectly from liver adaptive 

response). In subchronic and chronic feeding studies in rats, mice and dogs, boscalid generally

caused decreased body weights and body weight gains (primarily in mice) and effects on the 

liver (increase in weights, changes in enzyme levels and histopathological changes) as well as on 

the thyroid (increase in weights and histopathological changes). Mode of action studies 

conducted in rats indicated that boscalid has a direct effect upon the liver and that the thyroid 

effects are secondary. A reversibility study in rats indicated that both liver and thyroid 

parameters returned to control values after the animals were placed on control diet. Absolute 

and/or relative thyroid weights were elevated in rats and dogs, but there were no 

histopathological changes observed in the thyroid in either mice or dogs.

In a developmental toxicity study in rats, no developmental toxicity was observed in the fetuses 

at the highest dose tested (limit dose). No effects were noted in the dams in this study. In a 

developmental toxicity study in rabbits, an increased incidence of abortions or early delivery was 

observed at the limit dose. There was quantitative evidence of increased susceptibility in the 

two-generation reproduction study in rats, where decreases in body weights and body weight 

gains in male offspring were seen at a dose that was lower than the dose that induced 

parental/systemic toxicity. There was quantitative evidence of increased susceptibility in the 

developmental neurotoxicity study in rats, where decreases in pup body weights (PND 4) and 

body weight gains (PND 1-4) were seen in the absence of any maternal toxicity. 

In a two-year chronic toxicity study and a two-year carcinogenicity study in male and female 

rats, the combined data showed an increased trend in thyroid follicular cell adenomas that 

appeared to be treatment-related in males. This was supported by thyroid hypertrophy and 

hyperplasia of follicular cells at the same dose as well as increased thyroid weights plus 

mechanistic data. The mouse carcinogenicity study was negative. Boscalid was negative in the 

mutagenicity battery.

There was not evidence of neurotoxicity in rats in the acute, subchronic or developmental studies 

up to the limit dose. No neurotoxic observations were noted in any of the other studies in any 

species. 

In acute studies, there is relatively low toxicity (toxicity categories III or IV for oral, dermal, 

inhalation, primary eye irritation and primary skin irritation).
Page 20 of 53

4.4 Safety Factor for Infants and Children (FQPA Safety Factor)

A database of acceptable developmental, reproduction, and neurotoxicity (acute, subchronic and 

developmental) studies is available. Based on the weight-of-evidence considerations, it is 

determined that there is a low concern for increased susceptibility and pre- or post-natal toxicity

resulting from exposure to boscalid.

There was no evidence of increased susceptibility in the rat developmental study as no 

developmental toxicity was seen at the highest dose tested (limit dose).

There was evidence of increased qualitative susceptibility in the rabbit developmental study as 

characterized by an increased incidence of abortions or early delivery at the limit dose. It could 

not be ascertained if the abortions were the result of a treatment-related effect on the dams, the 

fetuses or both. It was concluded that the degree of concern is low because the increased 

abortions or early delivery was seen only at the limit dose and the abortions may have been due 

to maternal stress.

There was evidence of increased quantitative susceptibility seen in the rabbit developmental 

study and the developmental neurotoxicity study, in that reduced body weights were seen in the 

offspring at dose levels where no parental toxicity was observed. However, the degree of 

concern is low because the dose selected for chronic dietary and non-dietary exposure risk 

assessments would address the concern for the body weight effects, and the effect was shown to 

be reversible in the developmental neurotoxicity study.

Therefore, it was determined that the FQPA Safety Factor can be reduced to 1X because there is 

no evidence of susceptibility following in utero exposure to rats and there are low concern and 

no residual uncertainties in the developmental toxicity study in rabbits, in the 2-generation 

reproduction study or in the developmental neurotoxicity study after establishing toxicity

endpoints and traditional uncertainty factors to be used in the risk assessment.

4.4.1 Completeness of the Toxicology Database

The toxicity database is considered complete and adequate for risk assessment, with the 

exception of a subchronic inhalation study. All studies needed to assess susceptibility concerns, 

such as developmental and reproduction studies, have been submitted. Additional studies, such a 

developmental neurotoxicity study, acute and subchronic neurotoxicity studies and an 

immunotoxicity study are also available. The subchronic inhalation study is required because the 

use of an oral point of departure (POD) results in MOEs as low as 370 for occupational 

exposure, which the Hazard and Science Policy Council has determined is not sufficient to 

alleviate concern (TXR0056585. K.Rury. 03/04/2013). Therefore, a 10x database uncertainty

factor has been added for inhalation exposure.
Page 21 of 53

4.4.2 Evidence of Neurotoxicity

There was no evidence of neurotoxicity based on an acute neurotoxicity study, a 90-day

neurotoxicity study and a developmental neurotoxicity study (all in rats). There was no evidence 

of neurotoxicity in the other subchronic and chronic studies in the database.

4.4.3 Evidence of Sensitivity/Susceptibility in the Developing or Young Animal

There is no evidence of susceptibility following in utero exposure to rats and there are low 

concern and no residual uncertainties in the developmental toxicity study in rabbits, in the 2-

generation reproduction study or in the developmental neurotoxicity study after establishing 

toxicity endpoints and traditional uncertainty factors to be used in the risk assessment. 

There was no evidence of increased susceptibility in the developmental rat study as no 

developmental toxicity was seen at the highest dose tested (limit dose).

There was evidence of qualitative (not quantitative) increased susceptibility in the developmental 

rabbit study as characterized by an increased incidence of abortions or early delivery at the limit 

dose. It could not be ascertained if the abortions were the result of a treatment-related effect on 

either the dams, the fetuses, or both. The degree of concern is low because the increased 

abortions or early delivery was seen only at the Limit Dose and the abortions may have been due 

to maternal stress.

There was quantitative evidence of increased susceptibility in the two-generation reproduction 

study in rats, where decreases in body weights and body weight gains in male offspring were 

seen in the F2 generation at a dose that was lower than the dose that induced parental/systemic 

toxicity. However, the degree of concern is low because the dose selected for chronic dietary

and non-dietary exposure risk assessments would address the concern for the body weight 

effects.

There also was quantitative evidence of increased susceptibility in the developmental 

neurotoxicity study in rats, where decreases in pup body weights on post-natal day four (PND 4) 

and body weight gains (PND 1-4) were seen in the absence of any maternal toxicity. However, 

the degree of concern is low because the decreases in pup body weights seen on PND 1- 4 (and 

not at any other time periods) were reversible, in that no treatment-related effects on body

weight, body weight gain or any other parameter were noted at PND 21.

HED has concluded that there are no residual uncertainties for pre- and post-natal toxicity as the 

degree of concern is low for the susceptibility seen in the above studies, and the dose and 

endpoints selected for the overall risk assessments will address the concerns for the body weight 

effects seen in the offspring. Although the dose selected for overall risk assessments (21.8 

mg/kg/day) is higher than the NOAELs in the two-generation reproduction study (10.1 

mg/kg/day) and the developmental neurotoxicity study (14 mg/kg/day), these differences are 

considered to be an artifact of the dose selection process in these studies. For example, there is a 

10-fold difference between the LOAEL (106.8 mg/kg/day) and the NOAEL (10.1 mg/kg/day) in 
Page 22 of 53

the two generation reproduction study. A similar pattern was seen with regard to the 

developmental neurotoxicity study, where there is also a 10-fold difference between the LOAEL 

(147 mg/kg/day) and the NOAEL (14 mg/kg/day). There is only a 2-3 fold difference between 

the LOAEL (57 mg/kg/day) and the NOAEL (21.8 mg/kg/day) in the critical study used for risk 

assessment. Because the gap between the NOAEL and LOAEL in the 2-generation reproduction 

and developmental neurotoxicity studies was large and the effects at the LOAELs were minimal, 

the true no-observed-adverse-effect-level was probably considerably higher. Therefore, the 

selection of the NOAEL of 21.8 mg/kg/day from the 1-year dog study is conservative and 

appropriate for the overall risk assessments. In addition, the endpoints for risk assessment are 

based on thyroid effects seen in multiple species (mice, rats and dogs) and after various exposure 

durations (subchronic and chronic exposures) which were not observed at the LOAELs in either 

the two-generation reproduction or the developmental neurotoxicity studies. Based on these 

data, it is concluded that there are no residual uncertainties for pre- and post-natal toxicity.

(D290022 A. Levy. 09/08/2003)

4.4.4 Residual Uncertainty in the Exposure Database

There are no residual uncertainties identified in the exposure databases. The chronic dietary

food exposure assessments were performed using tolerance level residues, average percent crop 

treated estimates and 100% crop treated assumptions (for new proposed crops). EPA made 

conservative (protective) assumptions in the ground and surface water modeling used to assess 

exposure to boscalid in drinking water. EPA used similarly conservative assumptions to assess 

post-application exposure of adults and children. In addition, the residential exposure 

assessment is based on the updated 2012 Residential SOPs employing surrogate study data, 

including conservative exposure assumptions based on Day 0 contact to turf and surfaces treated 

at the maximum application rate. These data are reliable and are not expected to underestimate 

risks to adults or children. The Residential SOPs are based upon reasonable “worst-case” 

assumptions and are not expected to underestimate risk. Although some of the residue values

used in the dietary exposure assessment were slightly refined, these assessments will not 

underestimate the exposure and risks posed by boscalid. 

4.5 Toxicity Endpoint and Point of Departure Selections

4.5.1 Dose-Response Assessment

The endpoints and points of departure for this risk assessment as based on those of the previous 

risk assessment. The rationales for each selection, along with a detailed description of the 

toxicity studies used for various exposure scenarios are presented in that document (D290022. Y. 

Donovan 09/08/2003). Following is a summary:

Acute dietary endpoints: As there were no toxic effects attributable to a single dose, including 

the developmental toxicity studies, an endpoint of concern was not identified to quantify acutedietary risk to the general population or to the subpopulation females 13-49 years old. The 

changes in brain morphometrics seen in the developmental neurotoxicity study were not selected 

as they were observed only at a dose exceeding the limit dose (1442 mg/kg/day). Therefore, an 

acute RfD was not established for any population for boscalid.
Page 23 of 53

Chronic dietary endpoint: HED selected the NOAEL of 21.8 mg/kg/day for establishing the 

chronic RfD based on the combined results of the following three studies: chronic rat, 

carcinogenicity rat and chronic dog. While this NOAEL is higher than the NOAELs in the 90-

day study in dogs (7.6 mg/kg/day), the two-generation reproduction study (10.1 mg/kg/day) and 

the developmental neurotoxicity study (14 mg/kg/day), these differences are considered an 

artifact of the dose selection process in these studies as shown below:

Study NOAEL

(mg/kg/day)

LOAEL

(mg/kg/day)

LOAEL:NOAEL

Ratio

90-day - dog 7.6 78.1 10.3

2-generation reproduction - rat 10.1 101.6 10.0

developmental neurotoxicity - rat 14.0 147 10.5

1-year - dog 21.8 57.4 2.6

Because the gap between the NOAEL and LOAEL in these studies was large and the effects at 

the LOAELs were minimal (dog = increased alkaline phosphatase activity and hepatic weights; 

2-generation = decreased body weights and body weight gains in offspring; developmental 

neurotoxicity = decrease in pup body weight gains on post-natal days 1-4), the true no-observedadverse-effect-level was probably considerably higher. Therefore, the selection of the NOAEL 

of 21.8 mg/kg/day from the 1-year dog study is conservative and appropriate for the overall risk 

assessments. In addition, the endpoints for risk assessment are based on thyroid effects seen in 

multiple species (mice, rats and dogs) and after various exposure durations (subchronic and 

chronic exposures) which were not observed at the LOAELs in either the two-generation 

reproduction or the developmental neurotoxicity studies.

Occupational and Residential endpoints: All of the incidental oral, dermal and inhalation 

endpoints are based on the co-critical chronic toxicity rat, carcinogenicity rat and 1-year dog 

studies. Neither dermal nor systemic toxicity was seen at the limit dose (1000 mg/kg/day) in the 

28-day dermal toxicity study in rats. The oral NOAEL of 21.8 mg/kg/day was selected because 

of the concerns for the decreases in the body weight and body weight gains seen in the offspring 

in the two-generation reproduction and the developmental neurotoxicity studies. Additionally, 

this dose would be protective of the thyroid and hepatotoxicity seen via the oral route in multiple 

species (mice, rats and dogs) after various exposure durations (90-day, 1-year and 2-years). 

There are no concerns that the effects will worsen following longer treatment.

For the dermal endpoints, a dermal study is available; however, the selected endpoint addresses 

potential effects on offspring, which are not normally examined in the dermal study. This 

endpoint is likely to be conservative because no systemic effects were observed in the dermal 

study up to the limit dose of 1000 mg/kg/day. In the reproduction study, the parental NOAEL is 

112.6/1180.8 mg/kg/day based on decreases in body weight and body weight gain as well as 

hepatocyte degeneration in males only. No such effects were observed in the 28-day dermal 

study.

The use of an oral point of departure (POD) for inhalation exposure results in MOEs as low as 

370 for occupational exposure, which is not sufficient to alleviate concern (TXR0056585. K. 
Page 24 of 53

Rury. 03/04/2013). Therefore a 10X database uncertainty factor has been added for inhalation 

exposures.

4.5.2 Recommendation for Combining Routes of Exposure for Risk Assessment

As per FQPA, 1996, when there are potential residential exposures to a pesticide, aggregate risk 

assessment must consider exposures from three major sources: oral, dermal and inhalation 

exposures. Since all endpoints are from the same study, exposures from oral, dermal and 

inhalation exposure routes can be aggregated.

4.5.3 Cancer Classification and Risk Assessment Recommendation

The Cancer Assessment Review Committee (CARC) classified boscalid as, “suggestive evidence 

of carcinogenicity, but not sufficient to assess human carcinogenic potential”, and, therefore, the 

quantification of human cancer risk is not recommended (TXR0051289. J. Kidwell.

11/14/2002). The classification was based on data which were combined from two 2-year rat 

studies where males had a significant increasing trend and significant differences in pair-wise 

comparison with the controls for thyroid follicular cell adenomas. The increased incidence of 

these adenomas exceeded the historical control mean and range. This was supported by thyroid 

hypertrophy and hyperplasia of follicular cells, increased thyroid weights and mechanistic data. 

Combined study data for female rats showed only a borderline significant increasing trend for 

thyroid follicular cell adenomas. No increase over controls was noted in males or females for 

carcinomas. There was no increase in the incidence of any tumors of either sex in the 18-month 

mouse study. All mutagenic studies were negative with or without activation. Based on the 

overall weak evidence of carcinogenic effects, the CARC indicated that a dose-response 

assessment for cancer (either linear low-dose extrapolation or margin of exposure calculation) 

was not needed.

4.5.4 Summary of Points of Departure and Toxicity Endpoints Used in Human Risk 

Assessment

Table 4.5.4.1. Summary of Toxicological Doses and Endpoints for Boscalid for Use in Dietary and NonOccupational Human Health Risk Assessments.

Exposure/ 

Scenario

Point of 

Departure

Uncertainty/F

QPA Safety 

Factors

RfD, PAD, 

Level of 

Concern for 

Risk 

Assessment

Study and Toxicological Effects

Acute Dietary (All 

Populations, 

including Infants and 

Children and Females 

13-49 years of age)

NA NA NA No appropriate endpoint attributable to a 

single dose was not identified

Chronic Dietary 

(All Populations)

NOAEL= 

21.8 

mg/kg/day

UFA= 10x

UFH=10x

FQPA SF= 1x

Chronic RfD = 

0.218

mg/kg/day

cPAD = 0.218 

mg/kg/day

Co-critical chronic rat, carcinogenicity rat, 

and 1-year dog studies

LOAEL = 57-58 mg/kg/day based on liver 

and thyroid effects
Page 25 of 53

Table 4.5.4.1. Summary of Toxicological Doses and Endpoints for Boscalid for Use in Dietary and NonOccupational Human Health Risk Assessments.

Exposure/ 

Scenario

Point of 

Departure

Uncertainty/F

QPA Safety 

Factors

RfD, PAD, 

Level of 

Concern for 

Risk 

Assessment

Study and Toxicological Effects

Incidental Oral 

Short-Term (1-30 

days) & 

Intermediate-Term

(1-6 months)

NOAEL= 

21.8 

mg/kg/day

UFA= 10x

UFH=10x

FQPA SF= 1x

Residential 

LOC for MOE 

= 100

Co-critical chronic rat, carcinogenicity rat, 

and 1-year dog studies

LOAEL = 57-58 mg/kg/day based on liver 

and thyroid effects

Dermal Short-Term

(1-30 days) & 

Intermediate-Term

(1-6 months)

NOAEL= 

21.8 

mg/kg/day

UFA= 10x

UFH=10x

FQPA SF= 1x

Residential 

LOC for MOE 

= 100

Co-critical chronic rat, carcinogenicity rat, 

and 1-year dog studies

LOAEL = 57-58 mg/kg/day based on liver 

and thyroid effects

Inhalation ShortTerm (1-30 days)

& IntermediateTerm (1-6 months)

NOAEL= 

21.8 

mg/kg/day

UFA = 10x

UFH = 10x

UFDB = 10x

FQPA SF= 1x

Residential 

LOC for MOE 

= 1000

Co-critical chronic rat, carcinogenicity rat, 

and 1-year dog studies

LOAEL = 57-58 mg/kg/day based on liver 

and thyroid effects

Cancer (oral, 

dermal, inhalation)

Classification: “suggestive evidence of carcinogenicity, but not sufficient to assess human 

carcinogenic potential”; quantification of human cancer risk is not recommended. 

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

used to mark the beginning of extrapolation to determine risk associated with lower environmentally relevant human 

exposures. NOAEL = no observed adverse effect level. LOAEL = lowest observed adverse effect level. UF = 

uncertainty factor. UFA = extrapolation from animal to human (interspecies). UFH = potential variation in 

sensitivity among members of the human population (intraspecies). UFDB = to account for the absence of key data 

(i.e., lack of a critical study). FQPA SF = FQPA Safety Factor. PAD = population adjusted dose (a = acute, c = 

chronic). RfD = reference dose. MOE = margin of exposure. LOC = level of concern. N/A = not applicable.

Table 4.5.4.2. Summary of Toxicological Doses and Endpoints for Boscalid for Use in Occupational Human 

Health Risk Assessments

Exposure/ 

Scenario

Point of 

Departure

Uncertainty 

Factors

Level of Concern 

for Risk 

Assessment

Study and Toxicological Effects

Dermal ShortTerm (1-30 

days)

NOAEL= 

21.8 

mg/kg/day

UFA = 10x

UFH =10x

FQPA SF= 1x

Occupational 

LOC for MOE = 

100

Co-critical chronic rat, carcinogenicity rat, 

and 1-year dog studies

LOAEL = 57-58 mg/kg/day based on liver 

and thyroid effects

Dermal 

IntermediateTerm (1-6 

months)

NOAEL= 

21.8 

mg/kg/day

UFA = 10x

UFH = 10x

FQPA SF= 1x

Occupational 

LOC for MOE = 

100

Co-critical chronic rat, carcinogenicity rat, 

and 1-year dog studies

LOAEL = 57-58 mg/kg/day based on liver 

and thyroid effects

Inhalation 

Short-Term (1-

30 days)

NOAEL= 

21.8 

mg/kg/day

UFA = 10x

UFH=10x

UFDB = 10x

FQPA SF= 1x

Occupational 

LOC for MOE = 

1000

Co-critical chronic rat, carcinogenicity rat, 

and 1-year dog studies

LOAEL = 57-58 mg/kg/day based on liver 

and thyroid effects

Inhalation 

Intermediateterm (1-6 

months)

NOAEL= 

21.8 

mg/kg/day

UFA = 10x

UFH =10x

UFDB = 10x

FQPA SF = 1x

Occupational 

LOC for MOE = 

1000

Co-critical chronic rat, carcinogenicity rat, 

and 1-year dog studies

LOAEL = 57-58 mg/kg/day based on liver 

and thyroid effects

Cancer (oral, 

dermal, 

inhalation)

Classification: “suggestive evidence of carcinogenicity, but not sufficient to assess human 

carcinogenic potential”; quantification of human cancer risk is not recommended. 
Page 26 of 53

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

used to mark the beginning of extrapolation to determine risk associated with lower environmentally relevant human 

exposures. NOAEL = no observed adverse effect level. LOAEL = lowest observed adverse effect level. UF = 

uncertainty factor. UFA = extrapolation from animal to human (interspecies). UFH = potential variation in 

sensitivity among members of the human population (intraspecies). UFDB = to account for the absence of key data 

(i.e., lack of a critical study). MOE = margin of exposure. LOC = level of concern. N/A = not applicable.

5.0 Dietary Exposure and Risk Assessment 

5.1 Residues of Concern Summary and Rationale

The residues of concern for dietary risk assessment and the tolerance expression are summarized 

in Table 5.1 (HED MARC, DP286786, M. Nelson, 1/9/03). HED has concluded that the residue 

of concern in plants is boscalid for purposes of tolerance enforcement and risk assessment. The 

nature of boscalid residues in livestock is adequately understood, based upon acceptable 14C 

metabolism studies conducted on lactating goats and laying hens. In both goats and hens, parent 

boscalid, M510F01 (hydroxy metabolite), and M510F 02 (M510F01 glucuronide) were 

identified as the major residues, each with ≥10% TRR. No amide bridge cleavage products 

were identified. Based on the structural similarity of boscalid and M510F 01, and the fact that 

the enzymatic hydrolysis step in the proposed enforcement method will release M510F 02 back

to free M510F 01, HED concluded that the combined residues of parent boscalid, M510F 01 and 

M510F02 are the residues of concern in livestock matrices for purposes of risk assessment and 

the tolerance expression. 

For drinking water, the residue of concern for boscalid is the parent only.

Table 5.1. Summary of Metabolites and Degradates to be included in the Risk Assessment and Tolerance

Expression.

Matrix Residues included in Risk 

Assessment

Residues included in 

Tolerance Expression

Plants

Primary Crop parent parent

Rotational Crop parent parent

Livestock

Ruminant parent, M510F 01 & M510F02 parent, M510F 01 & M510F02

Poultry parent, M510F 01 & M510F02 parent, M510F 01 & M510F02

Drinking Water parent only Not Applicable

5.2 Food Residue Profile

Field trial data on artichoke (MRID 48897401), Belgium endive (MRID 48897402), and 

persimmon (MRID 48897403) have been submitted to support the proposed tolerances. These 

data are adequate to support dietary risk assessment as well as the proposed tolerances of 

boscalid on artichoke, Belgium endive, and persimmon. The number and geographic distribution 

of the field trials are adequate. The analytical method was demonstrated to be acceptable via 

concurrent recoveries of fortified control samples. The intervals of frozen storage of samples are 

covered by previous storage stability studies, and no corrections for loss of residue are needed. 

The trials were conducted according to the proposed labels (single and seasonal application rates, 
Page 27 of 53

PHI). Summaries of the residue data from the crop field trials are presented in Appendix D, 

Table D-1 through D-3.

Greenhouse Grown Tomato Transplants Grown for Home Consumer Market

BASF Corporation has requested the addition of greenhouse tomato use for commercial 

production and for tomato transplants grown for the home consumer market to the PageantTM 

Fungicide label (EPA Reg. No. 7969-251). This product is identical to PristineTM Fungicide 

(EPA Reg. No. 7969-199), which includes use on greenhouse tomatoes, but does not cover 

tomato transplants for consumers or use of lathe type structures. No residue chemistry data were 

submitted with this request.

Residues on tomato fruits from such use of PristineTM Fungicide (EPA Reg. No. 7969-199) for 

tomato transplants in green house, lath house, and other production structures would be expected 

to be less than those found in the greenhouse trials supporting the approved greenhouse use. The 

existing tolerance for fruiting vegetables will cover the requested new uses of the PageantTM 

Fungicide (EPA Reg. No. 7969-251) formulation.

Residential Use of FT09 (EPA File Symbol 4-UII) on Pome Fruit, Stone Fruit, and Tree Nuts

The submitted use directions are sufficient to allow for evaluation of the proposed residential use 

of FT09 based on comparison to the existing BASF Pristine®label for agricultural uses. The 

BASF formulation is a water dispersible granule. It is a solid material that forms a dispersion 

when mixed with water. The Bonide formulation is a suspension concentrate or suspension of 

solid materials in water. It also will form a dispersion when mixed with water. The formulations 

are expected to behave similarly when applied in the same manner (same rate) to crops. The 

Organization of Economic Cooperation and Development (OECD) Crop Field Trial Guidance 

recognizes such formulations as yielding the same residues at PHIs greater than 7 days. All 

relevant Bonide PHIs exceed 7 days, and therefore the resulting residues based on formulation 

will not be greater than residues from the BASF formulation.

The PHIs for the Bonide formulation are equal to or longer/greater than the BASF Pristine® 

formulation PHIs. Therefore, residues from use on the Bonide formulation are anticipated to be 

no more than or less than residues from the BASF formulation, based on comparison of the PHIs. 

The application rates (lbs ai/A) for the Bonide formulation, both per application and per season, 

are approximately equal to or less than the corresponding application rates for the BASF 

Pristine® formulation. Therefore, residues from the use of the Bonide formulation are 

anticipated to be no more than or less than residues from the BASF formulation, based on 

comparison of the application rates.

Residential use of the Bonide FT09 per the proposed label will not yield residues in excess of 

those from agricultural use of the BASF formulation Pristine®per the approved label. 

Processed Food and Feed

There are no proposed uses that are relevant to this guideline topic. There are no processed 

commodities on artichoke, Belgium endive, or persimmon of regulatory interest.
Page 28 of 53

Livestock

There are no proposed uses that are relevant to this guideline topic. There are no feed items 

associated with artichoke, Belgium endive, or persimmons. Therefore, the previous livestock 

dietary intake calculations and resulting tolerance recommendations are not changed.

Rotational Crops

The nature of the residue in rotational crops is adequately understood and was summarized in a 

previous residue chemistry summary document (DP278385, M. Nelson, 8/15/03). HED has 

concluded that the residue of concern in rotated crops for purposes of risk assessment and the 

tolerance expression is parent compound. Adequate limited and extensive field rotational crop 

studies are available supporting the existing tolerances for indirect residues in rotational crops. 

These data support the label-specific plant-back interval of 14 days for crops without boscalid 

uses. No additional rotational crop data are required for purposes of this petition. 

5.3 Water Residue Profile

The drinking water residues used in the dietary risk assessment were provided by EFED 

(D409880, K. White, 04/17/2013) and incorporated directly into the dietary assessment. Water 

residues were incorporated in the DEEM-FCID into the food categories “water, direct, all 

sources” and “water, indirect, all sources.”

The drinking water assessment considered new uses on Belgium endive, globe artichoke, and 

persimmon and new uses on tomatoes in greenhouses and lath houses, and homeowner garden 

spray and ornamental applications. All existing uses were also considered.

Surface water estimated drinking water concentrations (EDWC) were determined in previous 

assessments. See Tier I Drinking Water Exposure Assessment for the Section 3 New Use of 

Boscalid on Various Agricultural Crops Including Cranberries (White, 2012, D405064) for a 

discussion of modeling and estimating surface water concentrations. The EDWCs for boscalid in 

surface water were calculated using the screening model FIRST (FQPA Index Reservoir 

Screening Tool; v.1.1.1; dated 03/25/08). Screening Concentration in Ground Water (SCIGROW v2.3, Jul. 29, 2003) is a regression model used as a screening tool to estimate pesticide 

concentrations found in ground water used as drinking water. Tier 1 ground water EDWCs for 

boscalid were derived with PRZM-GW (Pesticide Root Zone Model for Ground water, version 

1.0, August 31, 2012), using the GW-GUI (Graphical User Interface, version 1.0, August 31, 

2012). PRZM-GW is a one-dimensional, finite-difference model that estimates the 

concentrations of pesticides in groundwater. It accounts for pesticide fate in the crop root zone 

by simulating pesticide transport and degradation through the soil profile after a pesticide is 

applied to an agricultural field. PRZM-GW permits the assessment of multiple years of pesticide 

application (up to 100 years) on a single site. Six standard scenarios, each representing a 

different region known to be vulnerable to ground water contaminations, are available for use 

with PRZM-GW for risk assessment purposes.

The maximum Tier 1 estimated chronic ground water EDWC is 697 ppb. The maximum Tier 1 

estimated chronic surface water EDWC is 26.4 ppb. This is based on turf use. The ground water 

value is higher than the surface water value and was therefore used in the assessment. The 
Page 29 of 53

EFED models and their descriptions are available at the EPA internet site: 

http://www.epa.gov/oppefed1/models/water/. See Table 5.3.1.

Table 5.3.1. Tier I EDWCs Based on Boscalid Use on Turf.

1

Source of Drinking Water Acute

(μg/L)

Annual Average or Post 

Breakthrough Average

(μg/L)

Surface water 97.3 26.4

Ground water 773 697

1 These are the highest EDWCs for the proposed and relevant previously evaluated use scenarios.

5.4 Dietary Risk Assessment

5.4.1 Description of Residue Data Used in Dietary Assessment

The dietary exposure analysis incorporates all current and proposed tolerances for residues of 

boscalid, including its metabolites and degradates. 

Since no observed effects could be attributed to a single dose, an acute endpoint was not 

established. Therefore, an acute dietary exposure assessment was not conducted.

A partially refined chronic dietary analysis was conducted. The chronic dietary exposure and 

risk assessment is based on tolerance-level residues for all commodities. The data used in the 

2009 dietary assessments were also used in this current analysis except for the addition of 

tolerances for globe artichoke, Belgium endive, and persimmon. The Biological Economic 

Analysis Division (BEAD) has provided percent crop treated information for boscalid (J.

Alsadek, BEAD, 03/08/2013). The EDWC for boscalid (697 μg/L) was calculated based on a 

turf scenario for ground water.

The analysis includes HED-recommended tolerance level residue values for the herb subgroup 

19A, although these tolerances were never finalized. The tolerances were recommended in 

connection with PP# 6E7164 and PP#7F7169 (DP 336632, C. Olinger, 11/27/2007). At the 

request of the Registration Division, a value of 0.5 ppm was used for honey, based on the 

existing tolerance in the European Union.

No new experimental processing data were incorporated into this analysis. The processing 

factors from earlier dietary assessments were derived as follows. For processed commodities 

where data were available to show no concentration (apple juice, dried plum prunes, rice bran, 

wheat flour, sunflower oil, mint oil, tomato puree, tomato juice, soybean oil, and cottonseed oil), 

the processing factor was set to 1. For processed commodities where the raw agricultural 

commodity (RAC) tolerance is adequate to cover the very slight concentration seen in the 

processing study (wheat germ, wheat bran, and tomato paste), the residue was set at the RAC 

level and the processing factor was reduced to 1. For processed commodities with established 

tolerances (raisin, peanut oil, and citrus oil), the processed commodity tolerance was used and 

the processing factor was set to 1.0. For all other processed commodities for which data were 

not available, DEEM (version 7.81) processing factors were used (DP# 336633, D. Davis, 

12/17/2007).
Page 30 of 53

Boscalid is classified as “not likely to be carcinogenic to humans”. Therefore, a cancer dietary

exposure assessment was not conducted.

5.4.2 Percent Crop Treated Used in Dietary Assessment

BEAD has provided percent crop treated information for boscalid (J. Alsadek, BEAD, 

03/08/2013). As a refinement, the weighted average %CT was incorporated. One hundred 

percent crop treated was assumed for commodities with no % CT data. 

The following average percent crop treated estimates were used in the chronic dietary risk 

assessments for the crops that are currently registered for boscalid: almonds 40%; apples 15%; 

apricots 25%; green beans 5%; blueberries 35%; broccoli <2.5%; cabbage 5%; caneberries 45%; 

cantaloupes 5%; carrots 15%; cauliflower 5%; celery <2.5%; cherries 45%; cucumbers 5%; dry

beans/dry peas <2.5%; garlic 5%; grapes 30%; hazelnuts 5%; lettuce 25%; nectarines 15%; 

onions 20%; peaches 20%; peanuts <1%; pears 15%; green peas <1%; peppers <2.5%; 

pistachios 30%; plums/prunes 5%; potatoes 20%; pumpkins 10%; squash 5%; strawberries 55%; 

tomatoes 5%; walnuts <1%; watermelons 25%.

5.4.3 Acute Dietary Risk Assessment

Since no observed effects could be attributed to a single dose, an acute endpoint was not 

established. Therefore, an acute dietary exposure assessment was not conducted.

5.4.4 Chronic Dietary Risk Assessments

The chronic dietary analysis was performed using tolerance level residues, average percent crop 

treated estimates, and 100% crop treated assumptions for new proposed uses. Dietary risk 

estimates were determined considering exposures from food plus drinking water. Boscalid 

exposure from the existing uses, including tolerance modifications to harmonize with Codex, and

the proposed new uses on persimmon, Belgium endive, and globe artichoke results in estimated 

risks that are below the Agency’s level of concern for food plus drinking water. The highest 

exposure and risk estimates for food plus drinking water utilized 20% of the chronic population 

adjusted dose (cPAD) for the U.S. population and 56% for children 1-2 years old, the most 

highly exposed population subgroup.
Page 31 of 53

5.4.5 Summary Table

Table 5.4.5 Summary of Dietary (Food and Drinking Water) Exposure and Risk for Boscalid 1,2

Population Subgroup

Acute Dietary Chronic Dietary Cancer

Dietary 

Exposure 

(mg/kg/day)

% aPAD

Dietary 

Exposure

(mg/kg/day)

% cPAD

Dietary 

Exposure

(mg/kg/day)

Risk

General U.S. Population

N/A N/A

0.042751 20

N/A N/A

All Infants (< 1 year old) 0.091079 42

Children 1-2 years old 0.121118 56

Children 3-5 years old 0.088299 41

Children 6-12 years old 0.047744 22

Youth 13-19 years old 0.029796 14

Adults 20-49 years old 0.036670 17

Adults 50+ years old 0.038128 18

Females 13-49 years old 0.036893 17

1The population subgroup with the highest estimated chronic dietary (food + drinking water) exposure and risk is indicated by 

bold text.

2NA = not applicable

6.0 Residential (Non-Occupational) Exposure/Risk Characterization

The proposed residential uses for boscalid will result in residential handler and post-application 

exposures. In addition, the existing use on golf course turf (Emerald Fungicide label; EPA Reg. 

No. 7969-1964) was reassessed in this document to reflect updates to HED’s 2012 Residential 

SOPs2along with policy changes for body weight assumptions, since the revisions to these 

exposures could impact the human health aggregate risk assessment for boscalid. Registered and 

proposed products do not lead to any residential handler or post-application risk estimates of 

concern.

6.1 Residential Handler Exposure

The residential handler assessment includes short-term exposures via the dermal and inhalation 

routes from treating gardens, trees, and turf. 

HED’s LOC for the MOE is defined by the uncertainty factors that are applied to the assessment. 

HED applies a 10X factor to account for variability among species and a 10X factor to account 

for variability within species. The total uncertainty factor that has been applied to the non-cancer 

 

2 Available: http://www.epa.gov/pesticides/science/residential-exposure-sop.html
Page 32 of 53

dermal assessment of boscalid is 100X for residential exposure. Residential dermal exposure 

and risk resulting in MOEs greater than or equal to 100 will not be of concern to HED (LOC = 

100). For inhalation exposures, an additional 10X uncertainty factor is added because of the 

database gap for lack of an available subchronic inhalation toxicity study. Therefore, the total 

uncertainty factor that has been applied to the non-cancer inhalation assessments of boscalid is 

1000X for residential handler exposure. Residential inhalation exposure and risk resulting in 

MOEs greater than or equal to 1000 will not be of concern to HED (LOC = 1000). 

Dermal and inhalation risk estimates were combined in this assessment because the PODs are 

based on the same toxicological study, thus the effects for these exposure routes are the same. 

Dermal and inhalation risk estimates were combined using the total aggregated risk index (ARI) 

methodology since the LOCs for dermal exposure (100) and inhalation exposure (1,000) are 

different. The LOC ARI is 1; therefore, ARIs of less than 1 are risk estimates of concern. 

Summaries of the inhalation and dermal risk estimates for residential handlers are included in 

Table 6.1. The maximum application rate for each exposure scenario is presented as the worst 

case scenario. The residential handler ARIs range from 24 to 330. Therefore, the dermal and 

inhalation risk estimates to residential handlers are not of concern to HED for any of the 

residential handler scenarios.
Page 33 of 53

Table 6.1. Residential Handler Non-cancer Exposure and Risk Estimates for Boscalid.

Exposure Scenario 

Dermal 

Unit 

Exposure 

(mg/lb ai)

Inhalation 

Unit 

Exposure 

(mg/lb ai)

Maximum 

Application Rate1

Area 

Treated or 

Amount 

Handled 

Daily2

Dermal Inhalation

Total ARI7

Dose 

(mg/kg/day)3 MOE4 Dose 

(mg/kg/day)5 MOE6

Mixer/Loader/Applicator

Liquid Garden/Trees : 

manually pressurized handwand

63 0.018 0.0076 lb ai/gal 5 gal 0.0045 4,900 0.0000086 2,500,000 48

Liquid Garden/Trees : 

manually pressurized handwand

63 0.018 0.0000051 lb ai/ft21200 ft20.00072 30,000 0.0000014 16,000,000 300

Liquid Garden/Trees : 

hose-end sprayer

58 0.0014 0.0000051 lb ai/ft21200 ft20.00067 33,000 0.00000011 200,000,000 330

Liquid Garden/Trees : 

hose-end sprayer

58 0.0014 0.0076 lb ai/gal 11 gal 0.0091 2,400 0.0000015 15,000,000 24

Liquid Garden/Trees : 

backpack sprayer 130 0.14 0.0000051 lb ai/ft2

1200 ft20.0015 15,000 0.000011 2,000,000 140

Liquid Garden/Trees : 

backpack sprayer

130 0.14 0.0076 lb ai/gal 5 gal 0.0093 2,400 0.000067 330,000 22

Liquid Garden/Trees : 

sprinkler can

58 0.0014 0.0000051 lb ai/ft21200 ft20.00067 33,000 0.00000011 200,000,000 330

Liquid Garden/Trees : 

sprinkler can 58 0.0014 0.0076 lb ai/gal 5 gal 0.0041 5,300 0.00000067 33,000,000 53

1 Based on the proposed garden/tree use on Bonide FT09 label (EPA Reg. No. 4-UII) 

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

3 Dermal Dose = Dermal Unit Exposure (mg/lb ai) × Application Rate (lb ai/acre or gal) × Area Treated or Amount Handled (A/day or gallons/day) × Dermal Absorption Factor 

(15%) ÷ Body Weight (80 kg).

4 Dermal MOE = Dermal NOAEL (21.8 mg/kg/day) ÷ Dermal Dose (mg/kg/day).

5 Inhalation Dose = Inhalation Unit Exposure (21.8 mg/lb ai) × Application Rate (lb ai/acre or gal) × Area Treated or Amount Handled (A/day or gallons/day) ÷ BW (80 kg).

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

7 Aggregate Risk Index (ARI) = 1÷ (1 ÷ RIdermal) + (1 ÷ RIinhalation) 

 Risk Index (RI) = MOE ÷ LOC; Inhalation LOC = 1,000 and Dermal LOC = 100
Page 34 of 53

6.2 Post-Application Exposure

There is the potential for dermal post-application exposure for individuals as result of being in an 

environment that has been previously treated with boscalid. Incidental oral exposure to children 

1 to <2 years old is not expected from treated turf because boscalid is only registered for use on 

golf course turf only and proposed for use on residential gardens and trees. Short-term dermal 

exposures were assessed for adults, youth 11 to 16 years old, and children 6 to 11 years old. 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 

SOPs6.

Summary of Residential Post-application Non-Cancer Exposure and Risk Estimates

All the short-term MOEs for each scenario are greater than the LOC of 100, and therefore, are 

not of concern. A TTR study is not required at this time for boscalid since the lowest dermal

MOE (10,000) is greater than 10 times the LOC based on default values for the fraction of 

application rate available for transfer after a turf application. Additionally, DFR studies are not 

required at this time for boscalid since the lowest dermal MOE (690) is greater than 4 times the 

LOC based on default input values.

Table 6.2. Residential Post-application Non-cancer Exposure and Risk Estimates for Boscalid.

Lifestage

Post-application Exposure Scenario

Application 

Rate1

Dose 

(mg/kg/day) MOEs2

Use Site Route of Exposure

Adult

Gardens Dermal 0.33 lb ai/A

0.032 690

Child (6-11 yrs) 0.022 1000

Adult Fruit and Nut Trees Dermal 0.22 lb ai/A 0.0019 11,000

Child (6-11 yrs) 0.0013 16,000

Adult

Lawn/Turf

Dermal Golfing

0.35 lb ai/A

0.0015 14,000

Youth (11-16 yrs) Dermal Golfing 0.0018 12,000

Child (6-11 yrs) Dermal Golfing 0.0021 10,000

1 Based on the proposed tree use on Bonide FT09 label (EPA Reg. No. 4-UII); the proposed garden use on Homeowner Garden 

Spray SC (EPA Reg. No. 7969-GLG); the proposed tomato transplant use on Pagent® Fungicide (EPA Reg. No.7969-251);

and the registered golf turf use on Emerald® Fungicide label (EPA Reg. No. 7969-196).

2 Dermal MOE = Dermal NOAEL (21.8 mg/kg/day) ÷ Dermal Dose (mg/kg/day).

6.3 Combined Residential Risk Estimates (Multiple Exposure Scenarios)

Because dermal post-application exposures to treated gardens, fruit or nut trees, and turf could 

conceivably co-occur within the same day for adults and children 6 to 11 year olds, combined 

exposures from these scenarios were considered. However, all four of these use sites/scenarios 

are proposed on different labeled products containing boscalid; therefore, the probability of cooccurrence is considered improbable. Therefore, assessments of these combined exposures were 

not conducted. 
Page 35 of 53

6.4 Residential Risk Estimates for Use in Aggregate Assessment

The scenarios with the highest exposures and corresponding lowest MOEs provided in Tables 

6.1 and 6.2 reflect the residential risk estimates that are recommended for use in the aggregate 

assessment for boscalid. Table 6.4 presents the residential risk estimates that are recommended 

for use in the aggregate assessment for boscalid.

 The recommended residential dermal exposure for use in the adult aggregate assessment 

reflects dermal exposure from post-application activities on treated gardens.

 The recommended residential dermal exposure for use in the youth (11-16 yr) aggregate 

assessment reflects dermal exposure from post-application golfing on treated turf.

 The recommended residential dermal exposure for use in the child (6-11 yr) aggregate 

assessment reflects dermal exposure from post-application activities in treated gardens.

Table 6.4. Recommendations for the Residential Exposures for the Boscalid Short-term Aggregate Assessments.

Lifestage Route of 

Exposure Scenario Dose1(mg/kg/day) MOE2

Adult Dermal Post-application activities in treated gardens 0.032 690

Youth (11-16 yr old) Dermal Post-application golfing on treated turf 0.0018 12,000

Child (6-11 yr old) Dermal Post-application activities in treated gardens 0.022 10,000

1 Daily Dose = See table 6.1 for adult handler scenarios and Table 6.2 for post-application scenarios.

2 MOE = NOAEL/Daily Dose

6.5 Residential Bystander Post-application Inhalation Exposure

Based on the Agency's current practices, a quantitative post-application inhalation exposure 

assessment was not performed for boscalid at this time primarily because of the low acute 

inhalation toxicity (Toxicity Category IV), low vapor pressure (5.3 x 10-9 mm Hg at 200 C), and

the low proposed use rates (0.22 to 0.36 lb ai/A). However, 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, 20103. The Agency is in the 

process of evaluating the SAP report and may, as appropriate, develop policies and procedures to 

identify the need for and, subsequently, the way to incorporate post-application inhalation 

exposure into the Agency's risk assessments. If new policies or procedures are developed, the 

Agency may revisit the need for a quantitative post-application inhalation exposure assessment 

for boscalid.

6.6 Spray Drift

Spray drift is always a potential source of exposure to residents nearby to spraying operations. 

This is particularly the case with aerial application, but, to a lesser extent, could also be a 

potential source of exposure from the ground application method employed for boscalid. The 

Agency has been working with the Spray Drift Task Force, EPA Regional Offices and State

 

3 Available: http://www.epa.gov/scipoly/SAP/meetings/2009/120109meeting.html
Page 36 of 53

Lead Agencies for pesticide regulation and other parties to develop the best spray drift 

management practices (see the Agency’s Spray Drift website for more information4). The 

Agency has completed its evaluation of the new database submitted by the Spray Drift Task 

Force, a membership of U.S. pesticide registrants, and is developing a policy on how to 

appropriately apply the data and the AgDRIFT computer model to its risk assessments for 

pesticides applied by air, orchard airblast and ground hydraulic methods. After the policy is in 

place, the Agency may impose further refinements in spray drift management practices to reduce 

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

Although a quantitative residential post-application inhalation exposure assessment was not 

performed as a result of pesticide drift from neighboring treated agricultural fields, an inhalation 

exposure assessment was performed for flaggers. This exposure scenario is representative of a 

worst case inhalation (drift) exposure and may be considered protective of most outdoor 

agricultural and commercial post-application inhalation exposure scenarios.

7.0 Aggregate Exposure/Risk Characterization

In accordance with FQPA, HED must consider and aggregate (add) pesticide exposures and risks 

from three major sources: food, drinking water, and residential exposures. In an aggregate 

assessment, exposures from relevant sources are added together and compared to quantitative 

estimates of hazard (e.g., a NOAEL or PAD), or the risks themselves can be aggregated. When 

aggregating exposures and risks from various sources, HED considers both the route and 

duration of exposure. For boscalid, potential exposures from food, drinking water, and 

residential scenarios were aggregated. 

This assessment considers the changes in the 2012 Residential SOPs implemented in January

2012. HED confirms that there are no exposure risks of concern resulting from boscalid on 

globe artichoke, Belgium endive, or persimmon, nor from utilizing the 2012 Residential SOPs to 

estimate residential exposure and risk. 

7.1 Acute Aggregate Risk

The aggregate acute risk estimates include exposure to residues of boscalid in food and drinking 

water, and does not include dermal, inhalation, or incidental oral exposure. However, since no 

observed effects could be attributed to a single dose, an acute endpoint was not established. 

Therefore, an acute dietary exposure assessment was not conducted.

7.2 Short-Term Aggregate Risk

There is potential short-term exposure to boscalid via dietary (which is considered background 

exposure) and residential (which is considered primary) exposure pathways. For adults, these 

pathways lead to exposure via oral (background) as well as dermal and inhalation (primary) 

routes. The most conservative scenarios were chosen for each. For a description of the 

residential exposure scenarios considered in the aggregate assessment, see Section 6.4. 

 

4 Available: http://www.epa.gov/opp00001/factsheets/spraydrift.htm 
Page 37 of 53

The non-cancer aggregate MOEs are 490 for children 6 to 11 years old, 1,300 for youths 11 to 16 

years old, and 410 for adults. None of these aggregate risk estimates are of concern to HED.

Table 7.2.1. Short-Term Aggregate Risk Calculations 

Lifestage Scenario

Dermal Exposure Oral Exposure

Total 

Combined 

MOE2

NOAEL

mg/kg/day

Exposure

mg/kg/day MOE1 NOAEL mg/kg/day

Chronic Dietary 

(Food + Water) 

mg/kg/day

MOE1

Child 6-11 yrs Post-application activities 

in treated gardens 21.8 0.022 990 21.8 0.047744 460 310

Youth 11-16 yrs Post-application golfing on 

treated turf 21.8 0.0018 12,000 21.8 0.029796 730 690

Adult Post-application activities 

in treated gardens 21.8 0.032 680 21.8 0.042751 510 290

1 The Level of Concern MOE is 100.

2 Total Combined MOE = 1/ [(1/MOEDermal) + (1/MOEOral)]

7.3 Chronic Aggregate Risk

Chronic exposure from the residential pathway is not anticipated based on the current boscalid

use pattern. The chronic aggregate risk (food and drinking water) is below HED’s LOC (i.e., 

<100% cPAD for the general U.S. population and all population subgroups). The dietary

exposure is estimated at 0.042751 mg/kg/day for the general U.S. population (20% of the cPAD) 

and 0.121118 mg/kg/day (56% of the cPAD) for children 1-2 years old, the population subgroup 

with the highest estimated chronic dietary exposure to boscalid. See Section 5.4.4 for details.

8.0 Cumulative Exposure/Risk Characterization

Unlike other pesticides for which EPA has followed a cumulative risk approach based on a 

common mechanism of toxicity, EPA has not made a common mechanism of toxicity finding as 

to boscalid and any other substances and boscalid does not appear to produce a toxic metabolite 

produced by other substances. For the purposes of this tolerance action, therefore, EPA has not 

assumed that boscalid has a common mechanism of toxicity with other substances. For 

information regarding EPA’s efforts to determine which chemicals have a common mechanism 

of toxicity and to evaluate the cumulative effects of such chemicals, see the policy statements 

released by EPA’s Office of Pesticide Programs concerning common mechanism determinations 

and procedures for cumulating effects from substances found to have a common mechanism on 

EPA’s website at http://www.epa.gov/pesticides/cumulative/.

9.0 Occupational Exposure/Risk Characterization

Boscalid is proposed for new occupational uses on globe artichoke, Belgium endive, persimmon, 

and greenhouse grown tomatoes. Application methods, maximum application rates, and use sites 

are summarized in Section 3.3 and Table 3.3. Based on the proposed use patterns, there is a 

potential for short- and intermediate-term occupational exposure to boscalid during handling 

(mixing, loading, and applying) and post-application activities. Boscalid uses are proposed for 

multiple applications, with the retreatment intervals ranging from 7 to 28 days. Additionally, for 

both dermal and inhalation exposures the same endpoint and point of departure were selected for 

short- and intermediate-term durations, and therefore, short-term exposure and risk estimates are 

considered to be protective of intermediate-term exposure and risk estimates. The proposed 
Page 38 of 53

labels require occupational handlers to wear the following personal protective equipment (PPE): 

long-sleeved shirts, long pants, chemical resistant gloves, and coveralls in a few cases. The 12 

hour restricted entry interval (REI) listed on the labels is appropriate. 

9.1 Short-/Intermediate-Term Handler Risk

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 

(amount of chemical used in each application), the kinds of equipment used, the target being 

treated, and the level of protection used by a handler can cause exposure levels to differ in a 

manner specific to each application event. 

Based on the anticipated use patterns from the proposed labels, types of equipment and 

techniques that can potentially be used, occupational handler exposure is expected from the 

proposed uses. HED’s LOC for the MOE is defined by the uncertainty factors that are applied to 

the assessment. HED applies a 10X factor to account for variability among species and a 10X 

factor to account for variability within species. The total uncertainty factor that has been applied 

to the boscalid occupational dermal exposure assessment is 100X. Occupational dermal 

exposure and risk resulting in MOEs greater than or equal to 100 will not be of concern to HED. 

For inhalation exposures, an additional 10X uncertainty factor is added because of the lack of an 

available subchronic inhalation toxicity study. Therefore, the total uncertainty factor that has 

been applied to the non-cancer inhalation assessments of boscalid is 1000X for residential 

handler exposure. Occupational inhalation exposure and risk resulting in MOEs greater than or 

equal to 1000 will not be of concern to HED (LOC = 1000). 

Dermal and inhalation risk estimates were combined in this assessment because the PODs are 

based on the same toxicological study, thus the effects for these exposure routes are the same. 

Dermal and inhalation risk estimates were combined using the total aggregated risk index (ARI) 

methodology since the LOCs for dermal exposure (100) and inhalation exposure (1,000) are 

different. The LOC ARI is 1; therefore, ARIs of less than 1 are risk estimates of concern. 

Summaries of the short- and intermediate-term non-cancer risk estimates for occupational 

handlers applying boscalid are provided in Appendix E, Table E-1. The dermal MOEs range 

from 410 (mixing/loading of WDG formulation to support aerial and chemigation applications to 

artichoke and persimmon) to 1800 (applying with aerial equipment to typical artichoke) at 

baseline PPE. All of the dermal MOEs are greater than the LOC of 100 when assessed using 

labeled PPE (baseline + gloves) and are not a concern to HED. 

The inhalation MOEs range from 1500 (mixing/loading of WDG formulation to support aerial 

and chemigation applications to artichoke and persimmon) to 400,000 (applying with manually 

pressurized equipment to greenhouse tomatoes) at baseline PPE (no respirator). All of the 

inhalation MOEs are greater than the LOC of 1,000 when assessed at baseline PPE and are not a 

concern to HED. Furthermore, all of the ARIs are greater than 1.0 when assessed using labeled 

PPE (baseline + gloves), and are not a concern to HED. 
Page 39 of 53

9.2 Short-and Intermediate-Term Post-Application Risk

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 reentry 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 on 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 activities, can greatly reduce the potential for post-application exposure.

9.2.1 Dermal Post-Application Risk

Based on the proposed use patterns, short- and intermediate-term post-application dermal 

exposures to workers re-entering treated areas is possible. Therefore, a post-application risk 

assessment for dermal exposures is needed. It should be noted that there is no post-application 

dermal exposure anticipated for the proposed Belgium endive use, because the roots are treated 

with pyraclostrobin prior to forcing in the trays. Thus there would be negligible exposure to the 

residue when the crop is harvested or maintained.

All post-application scenarios resulted in MOEs greater than 100 on day 0 (12 hours after 

application) and therefore are not of concern to HED. The MOEs for boscalid ranged from 400 

to 21,000. DFR studies are not required at this time for boscalid since the lowest dermal MOE 

(400) is greater than 4 times the LOC based on default input values. The short- and 

intermediate-term non-cancer post-application risk estimates for workers are provided in 

Appendix E, Table E-2. 

Restricted Entry Interval

The REI specified on the proposed label is based on the acute toxicity of boscalid. Boscalid is 

classified as Toxicity Category III via the dermal route and for skin irritation potential. Shortand intermediate-term post-application risk estimates were not a concern on day 0 (12 hours 

following application) for all post-application activities. Under 40 CFR 156.208 (c) (2) (iii), ai’s 

classified as Acute III or IV for acute dermal, eye irritation and primary skin irrigation are 

assigned a 12-hour REI. Therefore, the [156 subpart K] Worker Protection Statement interim 

REI of 12 hours is adequate to protect agricultural workers from post-application exposures to

boscalid.

9.2.2 Inhalation Post-Application Risk

Based on the Agency's current practices, a quantitative post-application inhalation exposure 

assessment was not performed for boscalid at this time primarily because of the low acute 

inhalation toxicity (Toxicity Category IV), low vapor pressure (5.3 x 10-9 mm Hg at 20o C) and 

the low proposed use rate (0.22 to 0.36 lb ai/A). However, there are multiple potential sources of 

post-application inhalation exposure to individuals performing post-application activities in 

previously treated fields. These potential sources include volatilization of pesticides and 
Page 40 of 53

resuspension of dusts and/or particulates that contain pesticides. The Agency sought expert 

advice and input on issues related to volatilization of pesticides from its Federal Insecticide, 

Fungicide, and Rodenticide Act Scientific Advisory Panel (SAP) in December 2009, and 

received the SAP’s final report on March 2, 20105. The Agency is in the process of evaluating 

the SAP report as well as available post-application inhalation exposure data generated by the 

ARTF and may, as appropriate, develop policies and procedures, to identify the need for and, 

subsequently, the way to incorporate occupational post-application inhalation exposure into the 

Agency's risk assessments. If new policies or procedures are put into place, the Agency may

revisit the need for a quantitative occupational post-application inhalation exposure assessment 

for boscalid.

Although a quantitative occupational post-application inhalation exposure assessment was not 

performed, an inhalation exposure assessment was performed for occupational/commercial 

handlers. Handler exposure resulting from application of pesticides outdoors is likely to result in 

higher exposure than post-application exposure. Therefore, it is expected that these handler 

inhalation exposure estimates would be protective of most occupational post-application 

inhalation exposure scenarios.

The Worker Protection Standard for Agricultural Pesticides contains requirements for protecting 

workers from inhalation exposures during and after greenhouse applications through the use of 

ventilation requirements [40 CFR 170.110, (3) (Restrictions associated with pesticide 

applications)].

10.0 References

S. Funk, 4/30/13, DP398877. Boscalid and Pyraclostrobin: Application by Bonide Products, 

Inc. to Register an End Use Product Containing Pyraclostrobin, Boscalid, and Lambda 

Cyhalothrin for Homeowner Use on Pome Fruit, Stone Fruit, and Tree Nuts. 

S. Funk, 4/30/13, DP406471. Pyraclostrobin and Boscalid: Request to Add Indoor Use on 

Greenhouse Tomato for Commercial Production and on Greenhouse/Lathhouse Transplants for 

Consumer Home Market. PagentTM Fungicide Reg. No. 7969-251.

S. Funk, 4/30/13, DP405063. Boscalid: Petition for the Establishment of Permanent Tolerances 

and Registration for Use on Belgium Endive, Persimmon, and Globe Artichoke. Request for 

Crop Group Expansions/Revisions for Bulb Vegetable Group 3-07, Fruiting Vegetable 8-10, 

Citrus Fruit Group 10-10, Pome Fruit Group 11-10, Berry Subgroups 13-07A, B, F, and G, and 

Oilseed Group 20. Summary of Analytical Chemistry and Residue Data. 

S. Funk, 6/24/13, DP410743. Revised: Boscalid. Chronic Aggregate Dietary (Food and 

Drinking Water) Exposure and Risk Assessments to Support New Uses on Globe Artichoke, 

Belgium Endive, and Persimmon.

C. Walls, 4/30/13, DP405533. Boscalid. Occupational and Residential Exposure Assessment 

for proposed new uses of boscalid on globe artichoke, Belgium endive, persimmon, greenhouse 

 

5 Available: http://www.epa.gov/scipoly/SAP/meetings/2009/120109meeting.html
Page 41 of 53

grown tomato transplants grown for home consumer market, and residential ornamentals, 

landscape gardens, fruit trees and nut trees.

K. White, 4/17/13, DP409880. Tier I Drinking Water Exposure Assessment for the Section 3 

New Uses of Boscalid on Various Agricultural Crops and Homeowner Uses.

Appendix A. Toxicology Profile and Executive Summaries

A.1 Toxicology Data Requirements

The requirements (40 CFR 158.500) for food uses are in the table below. Use of the new 

guideline numbers does not imply that the new (1998) guideline protocols were used.

Table A.1: Toxicology Studies Required Submitted Satisfied

870.1100 Acute Oral Toxicity ................................................................................................

870.1200 Acute Dermal Toxicity...............................................................................................

870.1300 Acute Inhalation Toxicity ..........................................................................................

870.2400 Acute Eye Irritation................................................................................................

870.2500 Acute Dermal Irritation..............................................................................................

870.2600 Skin Sensitization................................................................................................

yes

yes

yes

yes

yes

yes

yes

yes

yes

yes

yes

yes

yes

yes

yes

yes

yes

yes

870.3100 90-Day Oral Toxicity in Rodents................................................................

870.3150 90-Day Oral Toxicity in Non-Rodents................................................................

870.3200 21/28-Day Dermal Toxicity .......................................................................................

870.3250 90-Day Dermal Toxicity ............................................................................................

870.3465 90-Day Inhalation Toxicity ........................................................................................

yes

yes

yes

no (CR)

yes (CR)

yes

yes

yes

no

no

yes

yes

yes

---

no

870.3700 Prenatal Developmental Toxicity Study (Rodent)......................................................

870.3700 Prenatal Developmental Toxicity Study (Non-Rodent)................................

870.3800 Reproduction and Fertility Effects................................................................

yes

yes

yes

yes

yes

yes

yes

no

yes

870.4100 Chronic Toxicity (Rodent).........................................................................................

870.4100 Chronic Toxicity (Non-Rodent).................................................................................

870.4200 Carcinogenicity (Two Rodent Species; Rat and Mouse)................................

870.4300 Combined Chronic Toxicity/Carcinogenicity ............................................................

yes

no

yes

no

yes

yes

yes

no

yes

---

yes

yes

870.5100 Bacterial Reverse Mutation Test................................................................................

870.5300 in vitro Mammalian Cell Gene Mutation Test............................................................

870.5375 in vitro Mammalian Chromosome Aberration Test....................................................

870.5385 Mammalian Bone Marrow Chromosomal Aberration Test................................

870.5395 Mammalian Erythrocyte Micronucleus Test ..............................................................

870.5550 Unscheduled DNA Synthesis in Mammalian Cells in Culture................................

yes

yes

yes

---

yes

no

yes

yes

yes

no

yes

yes

yes

yes

yes

---

yes

---

870.6100 Delayed Neurotoxicity of Organophosphorus Substances (Acute, Hen)....................

870.6100 Delayed Neurotoxicity of Organophosphorus Substances (28-Day, Hen) .................

870.6200 Neurotoxicity Screening Battery (Acute, Rat) ...........................................................

870.6200 Neurotoxicity Screening Battery (Subchronic, Rat)...................................................

870.6300 Developmental Neurotoxicity Study ................................................................

no (CR)

no (CR)

yes

yes

no (CR)

no

no

yes

yes

no

---

---

yes

yes

---

870.7200 Companion Animal Safety.........................................................................................

870.7485 Metabolism and Pharmacokinetics................................................................

870.7600 Dermal Penetration ................................................................................................

in vitro Dermal Penetration........................................................................................

870.7800 Immunotoxicity................................................................................................

no (CR)

yes

no (CR)

no

yes

no

yes

yes

no

yes

---

yes

---

---

---

CR: Conditionally Required
Page 42 of 53

A.2 Toxicity Profiles

Table A.2.1. Acute Toxicity of Boscalid

Table A.2.1. Acute Toxicity Profile – Boscalid (BAS 510 F) Technical

Test Material

GDLN Study Type MRID Results

Tox

Category

Technical 870.1100 Acute Oral - rat 45404814 LD50 > 5000 mg/kg IV

Technical 870.1200 Acute Dermal -

rat

45404815 LD50 > 2000 mg/kg III

Technical 870.1300 Acute 

Inhalation

45404816 LC50 (M & F): > 6.7 

mg/L

IV

Technical 870.2400 Primary Eye 

Irritation

45404817 Not irritating to the eye IV

Technical 870.2500 Primary 

Dermal 

Irritation

45404818 Not irritating to the skin IV

Technical 870.2600 Dermal 

Sensitization

45404819 Study unacceptable as 

challenge dose was 

inadequate

N/A

Table A.2.2. Non-acute Toxicity Profile for Boscalid

Table A.2 Repeated Dose Toxicity Profile of Boscalid (BAS 510 F) Technical.

Guideline No. Study Type Results

870.3100 90-Day oral toxicity 

rodents (rats)

NOAEL: 34/159 mg/kg/day (M/F)

LOAEL: 137/395 mg/kg/day (M/F): M = increases 

in absolute and relative thyroid weights and 

increased incidence of thyroid hyperplasia as well as 

follicular epithelial hypertrophy; F = increases in 

absolute and relative thyroid weights.

870.3100 90-Day oral toxicity 

rodents (mice)

NOAEL: 197/2209 mg/kg/day (M/F)

LOAEL: 788/2209 mg/kg/day (M/F): M = increased 

liver weights and increased incidence of marked fatty 
Page 43 of 53

Table A.2 Repeated Dose Toxicity Profile of Boscalid (BAS 510 F) Technical.

Guideline No. Study Type Results

change in the liver; F = not attained

870.3150 90-Day oral toxicity in 

nonrodents (dogs)

NOAEL: 7.6/8.1 mg/kg/day (M/F)

LOAEL: 78.1/81.7 mg/kg/day (M/F): M = increased 

alkaline phosphatase activity and hepatic weights; F 

= increased alkaline phosphatase activity and hepatic 

weights.

870.3200 21/28-Day dermal toxicity

(rats)

NOAEL: 1000 mg/kg/day (HDT)

LOAEL: >1000 mg/kg/day

870.3700 Prenatal developmental in 

rodents (rats)

Maternal NOAEL: 1000 mg/kg/day

Maternal LOAEL: cannot be established

Developmental NOAEL: 1000 mg/kg/day

Developmental LOAEL: cannot be established

870.3700 Prenatal developmental in 

nonrodents (rabbit)

Maternal NOAEL: 300 mg/kg/day

Maternal LOAEL: 1000 mg/kg/day based on 

abortions or early delivery.

Developmental NOAEL: 300 mg/kg/day 

Developmental LOAEL: 1000 mg/kg/day based on 

abortions or early delivery.

870.3800 Reproduction and fertility 

effects (rat)

Parental systemic NOAEL:112.6/1180.8 mg/kg/day 

(M/F)

Parental systemic LOAEL:1165.0/>1180.8 

mg/kg/day (M/F) decreased body weight and body 

weight gain (F1) as well as hepatocyte degeneration 

F0 and F1) in males only.

Offspring systemic NOAEL:11.2/115.8 mg/kg/day 

(M/F)

Offspring systemic LOAEL:112.6/1180.8 

mg/kg/day (M/F): decreased body weight for F2 pups 

in males and females of both generations.

Reproductive NOAEL:1165.0/1180.8 mg/kg/day 

(M/F)

Reproductive LOAEL:>1165.0/1180.8 (M/F)

870.4100a Chronic toxicity rodents 

(rat)

NOAEL: 21.9/30.0 mg/kg/day (M/F)

LOAEL: 110.0/150.3 mg/kg/day (M/F): M = thyroid 

toxicity (weights and microscopic changes); F = 

thyroid toxicity (weights and microscopic changes).

Thyroid follicular cell adenomas: M = 0/20, 0/20, 

2/20,1/20; F = 0/20, 0/20, 1/20,0/20.

870.4100 Chronic toxicity dogs NOAEL: 21.8/22.1mg/kg/day (M/F)

LOAEL:57.4/58.3 mg/kg/day (M/F): M = elevated 

ALP activities and elevated hepatic weights; F = no 
Page 44 of 53

Table A.2 Repeated Dose Toxicity Profile of Boscalid (BAS 510 F) Technical.

Guideline No. Study Type Results

effects

870.4200 Carcinogenicity rats NOAEL: 23.0/29.7 mg/kg/day (M/F)

LOAEL: 116.1/155.6 mg/kg/day (M/F): M = 

increased incidence of thyroid follicular cell 

hyperplasia and hypertrophy; F = decrease in body 

weight gain and increased incidence of thyroid 

follicular cell hyperplasia and hypertrophy. Thyroid 

follicular cell adenomas: M = 0/50, 0/50, 1/50, 4/50; 

F = 0/50, 1/50, 0/50, 3/50.

870.4200 Carcinogenicity mice NOAEL:65/443 mg/kg/day (M/F)

LOAEL: 331/1804 mg/kg/day (M/F): M = decreases 

in body weight and body weight gains; F = decreases 

in body weight and body weight gains. No evidence 

of carcinogenicity.

870.4300 Chronic 

feeding/Carcinogenicity rat

See 870.4100a and 870.4200.

870.5100 Gene Mutation bacterial 

reverse mutation assay

Negative without and with S-9 activation up to limit 

dose of 5000 μg/plate.

870.5300 In vitro mammalian cell 

forward gene mutation 

assay (CHO cells/HGPRT 

locus)

Negative without and with S-9 activation up to the 

limit of solubility of 25 μg/mL.

870.5375 In vitro mammalian 

cytogenetics assay in 

Chinese hamster V79 cells

Negative without and with S-9 activation up to 3500 

μg/mL with precipitation showing at concentrations 

of 100 μg/mL and higher.

870.5395 Cytogenetics - mammalian 

erythrocyte micronucleus 

test in the mouse

Negative at doses up to 2000 mg/kg.

870.5500 In vitro unscheduled DNA 

synthesis (primary rat 

hepatocytes)

Negative response up to 50 μg/mL. Cytotoxicity at 100-

500 μg/mL.

870.6200 Acute neurotoxicity screening 

battery (rat)

NOAEL:2000/1000 mg/kg/day (M/F)

LOAEL: >2000/2000 mg/kg/day (M/F): F = piloerection

870.6200 Subchronic neurotoxicity 

screening battery (rat)

NOAEL:1050.0/1272.5 mg/kg/day (M/F)

LOAEL: >1050.0/1272.5 mg/kg/day (M/F)
Page 45 of 53

Table A.2 Repeated Dose Toxicity Profile of Boscalid (BAS 510 F) Technical.

Guideline No. Study Type Results

870.6300 Developmental neurotoxicity 

(rat)

Maternal NOAEL:1442 mg/kg/day

Maternal LOAEL: >1442 mg/kg/day

Offspring NOAEL: 14 mg/kg/day

Offspring LOAEL: 147 mg/kg/day (decreased body 

weights on PND 4 and decreased body weight gain on 

PNDs 1-4)

870.7485 Metabolism and 

pharmacokinetics (rat)

BAS 510 F was readily absorbed and excreted following 

single oral 50 mg/kg; at single 500 mg/kg or 15 doses of 

500 mg/kg, absorption was saturated. Excretion mainly by 

feces (80-98%). Biliary excretion 40-50% of fecal activity 

at 50 mg/kg, 10% at 500 mg/kg. Urine, about 16% at 50 

mg/kg, 3-5% at 500 mg/kg. Absorption about 56% at 50 

mg/kg and 13-17% at 500 mg/kg. Excretory patterns 

similar by gender or radiolabel position. Metabolites 

(hydroxylation and conjugation products) were consistent 

with Phase I oxidation reactions followed by Phase II 

conjugation with glucuronic acid or sulfate, or by 

conjugation of the parent with glutathione with cleavage to 

sulfate metabolites.

870.7800

Immunotoxicity

MRID 48203801 (2003)

0, 100, 1000, or 10000 ppm 

0, 7.45, 73.1, or 736.2 m/k/d

Acceptable / Guideline

NOAEL = 736.2 mg/kg/day

LOAEL = not established

870.7600 Dermal Penetration (rat) Maximum % absorption:

0.01 mg/cm2= 10.93 (24 hour exposure, 24 hour sacrifice)

0.10 mg/cm2= 3.76 (24 hour exposure, 24 hour sacrifice)

1.00 mg/cm2= 1.48 (10 hour exposure, 72 hour sacrifice)

none SPECIAL STUDY: Hepatic 

enzyme induction (rat)

1. hypertrophy of zone III hepatocytes

2. >20% increase in liver weight

3. increase in CYP450 activity

4. slight to extensive microscopic SER proliferation

5. not a peroxisome proliferator

6. enzymes in CYP450 subfamily not induced

7. no notable microscopic increase in size or number of 

peroxisomes

CONCLUSION: inducer of total CYP450 activity

none SPECIAL STUDY: Hormone 

and enzyme induction (rat)

1. slight (statistically significant) decrease in circulating T3

and T4 only in males

2. increase in circulating TSH levels both sexes

3. increase in all 3 liver microsomal 

glucuronyltransferases

CONCLUSION: disruption of thyroid homoeostasis by 

decreasing circulating T3 and T4 and increasing TSH; 
Page 46 of 53

Table A.2 Repeated Dose Toxicity Profile of Boscalid (BAS 510 F) Technical.

Guideline No. Study Type Results

likely the result of hepatic microsomal 

glucuronyltransferase induction

none SPECIAL STUDY: 

Reversibility study (dietary): 

4-week administration 

followed by 4 weeks recovery 

or 13 weeks recovery (rat)

4 weeks dosing: at 2500 and 15000 ppm: increase in TSH 

(68% and 87%); increase in absolute and relative thyroid 

weights, hypertrophy of thyroid follicular epithelial cells 

and diffuse follicular hyperplasia, increase in absolute and 

relative liver weights and centrilobular hypertrophy as 

well as liver portal fatty changes.

4 weeks dosing + 4 weeks recovery: no increases in TSH; 

increase in absolute and relative thyroid weights; thyroid 

hypertrophy and hyperplasia decreased to control values; 

all liver effects reversed to control.

4 weeks dosing + 13 weeks recovery: no increases in TSH; 

increase in absolute and relative thyroid weights; thyroid 

hypertrophy and hyperplasia decreased to control values; 

all liver effects reversed to control.

CONCLUSION: induction of liver microsomal enzyme 

system resulting in increased glucuronidation of thyroxine, 

resulting in an increase in TSH secretion as a 

compensatory response of the physiological negative 

feedback system; increased TSH resulted in increased 

thyroid weight.
Page 47 of 53

Appendix B. Physicochemical Properties of Boscalid.

Table B. Physicochemical Properties of Boscalid.

Parameter Value References

Melting point/range 142.8-143.8 C MRIDs 45404802 and 

pH NA (does not dissociate in water) 45404804-45404809

Relative Density (20oC) 1.381g/cm3

Water solubility (20oC) 4.64 mg/L at pH 6

Solvent solubility (g/100 mL at 20oC) acetone 16-20 ethyl acetate 6.7-8.0 

methanol 4-5 2-propanol <0.01 

acetonitrile 4-5 dichloromethane 20-25 

toluene 2-5 n-heptane <0.01

1-octanol <0.01 olive oil 2.9

N,N-DMF >25

Vapor pressure 7 x 10-9

hPa 

Dissociation constant, pKa None (does not dissociate in water)

Octanol/water partition coefficient, 

Log(KOW)

2.96 

UV/visible absorption spectrum UV molecular extinction (e[lmol-1cm-1]): 3.15 

x104at 228 nm; 1.53 x103at 290 nm

Appendix C. Review of Human Research

The PHED Task Force, 1995. The Pesticide Handlers Exposure Database, Version 1.1. 

Electronic Database. Task Force Members: Health Canada, U.S. EPA, and the National 

Agricultural Chemicals Associations, released February 1995. 

The Agricultural Handler Exposure Task Force (AHETF), 2011. The Occupational Handler Unit 

Exposure Surrogate Reference Table. U.S. EPA. Released June 21, 2011. 

Data from the Outdoor Residential Exposure Task Force (ORETF). 

HED Residential Standard Operating Procedures (2012). 
Page 48 of 53

Appendix D. Summaries of Field Residue Data

Table D-1. Summary of Residue Data from Globe Artichoke Crop Field Trials with Boscalid.

Commodity

Total Applic. 

Rate

(lb ai/A)

[kg ai/ha]

PHI 

(days) Analyte

Residue Levels1

(ppm)

n

Sample

Min.

Sample

Max. LAFT2 HAFT2 Median Mean Std. Dev.

Artichoke 

Flower 

Head

1.081-1.105

(1.21-1.24) 0 Boscalid 3 1.159 2.596 1.446 2.563 1.722 1.910 0.582

1

 Except for sample min/max, values reflect per trial averages; n = no. of field trials. Statistics were calculated by the study 

reviewer. 

2

 LAFT = lowest average field trial; HAFT = highest average field trial.

Table D-2. Summary of Residue Data from Belgium Endive Crop Field Trials with Boscalid.

Commodity Rate1 PHI 

(days) Analyte

Residue Levels2

(ppm)

n

Sample

Min.

Sample

Max. LAFT3 HAFT3 Median Mean Std. Dev.

Treatment 02: One pre-cold-storage application to roots

Belgium 

endive heads

1.14-1.18 g ai/100 lb

of roots 25-27 Boscalid 3 <0.05 0.15 <0.05 0.13 <0.075 <0.085 0.041

Treatment 03: One pre-forcing application to roots in packing tray

Belgium

endive heads 0.177-0.192 g ai/ft2

17-19 Boscalid 3 0.25 2.97 0.28 2.26 1.75 1.43 1.028

Treatment 04: One pre-cold-storage application to roots + One pre-forcing application to roots in packing tray

Belgium 

endive heads

1.16-1.17 g ai/100 lb

of roots and

0.182-0.199 g ai/ft2

17-19 Boscalid 3 0.43 1.41 0.455 1.255 1.05 0.92 0.416

1

 Rate for boscalid, as calculated by the study reviewer based on the certificate of analysis of applied product in the study report.

2

 Except for sample min/max, values reflect per trial averages; n = no. of field trials. For calculation of median, mean, and 

standard deviation, the LLMV (0.05 ppm) was used for any results reported as <LLMV 

3

 LAFT = lowest average field trial; HAFT = highest average field trial.

Table D-3 Summary of Residue Data from Persimmon Crop Field Trials with Boscalid.

Commodity

Total Applic. 

Rate

(lb ai/A)

[kg ai/ha]

PHI 

(days) Analyte

Residue Levels1

(ppm)

n

Sample

Min.

Sample

Max. LAFT2 HAFT2 Median Mean Std. Dev.

Persimmon 

Fruit

1.110-1.126

(1.24-1.26)

0 Boscalid 3 0.184 3.285 0.198 3.019 0.862 1.360 1.475

1

 Except for sample min/max, values reflect per trial averages; n = no. of field trials. Statistics were calculated by the study 

reviewer.

2

 LAFT = lowest average field trial; HAFT = highest average field trial.
Page 49 of 53

Appendix E. Summaries of Occupational Handler and Post-application Exposure and Risk Estimates

Table E-1. Occupational Handler Non-Cancer Exposure and Risk Estimates for Boscalid.

Exposure Scenario Crop

Dermal Unit 

Exposure 

(μg/lb ai)1

Inhalation 

Unit Exposure 

(μg/lb ai)1

Maximum

Application 

Rate2

(lb ai/A)

Area 

Treated or 

Amount 

Handled 

Daily3

Dermal Inhalation

ARI8

Baseline Baseline Dose 

(mg/kg/day)4 MOE5 Dose (mg/kg/day)6 MOE7

Mixer/Loader

Aerial applications of 

WDG

and

Chemigation application of 

WDG

Artichoke

Persimmon 227 8.96 0.18 350 0.054 410 0.014 1,500 1.1

Airblast application of 

WDG Persimmon 227 8.96 0.18 40 0.0061 3,600 0.0016 14,000 10

Chemigation application of 

WDG

and

Groundboom application 

of WDG

Greenhouse 

tomatoes 227 8.96 0.18 60 0.0092 2,400 0.0024 9,000 6.5

Groundboom application 

of WDG Artichoke 227 8.96 0.18 80 0.12 1,800 0.0032 6,700 4.9

Applicator

Aerial application Artichoke

Persimmon 5 0.068 0.18 350 0.0012 18,000 0.00011 200,000 95

Airblast application Persimmon 1770 4.71 0.18 40 0.048 460 0.00085 26,000 3.9

Groundboom application Greenhouse 

tomatoes 78.6 0.34 0.18 60 0.0032 6,800 0.000092 240,000 53

Groundboom application Artichoke 78.6 0.34 0.18 80 0.0042 5,100 0.00012 180,000 40

Flagger

Flagger Artichoke

Persimmon 11 0.35 0.18 350 0.0026 8,400 0.00055 40,000 27

Mixer/Loader/Applicator
Page 50 of 53

Table E-1. Occupational Handler Non-Cancer Exposure and Risk Estimates for Boscalid.

Exposure Scenario Crop

Dermal Unit 

Exposure 

(μg/lb ai)1

Inhalation 

Unit Exposure 

(μg/lb ai)1

Maximum

Application 

Rate2

(lb ai/A)

Area 

Treated or 

Amount 

Handled 

Daily3

Dermal Inhalation

ARI8

Baseline Baseline Dose 

(mg/kg/day)4 MOE5 Dose (mg/kg/day)6 MOE7

Backpack application of 

WDG

Greenhouse 

tomatoes 13,200 140 0.0018

lb ai/gal

40

gal 0.0036 6,100 0.00025 86,000 36

Manually pressurized 

handwand app of WDG

Greenhouse 

tomatoes 100,000 30 0.0018

lb ai/gal

40

gal 0.027 810 0.000054 400,000 7.9

Mechanically pressurized 

handgun of WDG

Artichoke

Persimmon 1300 3.9 0.0018lb ai/gal

1000

gal 0.0088 2,500 0.00018 120,000 21

Mechanically pressurized 

handgun of WDG

Greenhouse 

tomatoes 3500 120 0.0018

lb ai/gal

1000

gal 0.024 920 0.0054 4,000 2.8

Mechanically pressurized 

handgun of WDG

Belgium 

Endive – prior 

to cold storage

1300 3.9 0.000028 

lb ai/ lb root

200,000

lb root 0.014 1,600 0.00027 80,000 13

Mechanically pressurized 

handgun of WDG

Belgium 

Endive – prior 

to forcing

1300 3.9 0.0004

lb ai/ft2

10,890

ft2

0.011 2,100 0.00021 100,000 17

1 Based on the “Occupational Pesticide Handler Unit Exposure Surrogate Reference Table” (March 2013); 

2 Based on proposed label (See Table 4).

3 Exposure Science Advisory Council Policy #9.1.

4 Dermal Dose = Dermal Unit Exposure (μg/lb ai) × Conversion Factor (0.001 mg/μg) × Application Rate (lb ai/acre or gal) × Area Treated or Amount Handled Daily (A or gal/day) × DAF (%) ÷ BW 

(kg).

5 Dermal MOE = Dermal NOAEL (mg/kg/day) ÷ Dermal Dose (mg/kg/day).

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

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

8 Aggregate Risk Index (ARI) = 1÷ (1 ÷ RIdermal) + (1 ÷ RIinhalation) 

 Risk Index (RI) = MOE ÷ LOC; Inhalation LOC = 1,000 and Dermal LOC = 100
Page 51 of 53

Table E-2. Occupational Post-application Non-Cancer Exposure and Risk Estimates for Boscalid.

Crop/Site Activities Transfer Coefficient 

(cm2/hr)

DFR1

(μg/cm2)

Dermal Dose 

(mg/kg/day)2 MOE3

Artichoke

Hand Harvesting 1,100

1.01

0.0167 1,300

Hand Weeding, 

Thinning, Pruning 70 0.0011 21,000

Irrigation

(Hand Set) 1,900 0.029 760

Scouting 210 0.0032 6,900

Transplanting 230 0.0035 6,300

Persimmon

Scouting, Hand Pruning, 

Training 580

1.01

0.0088 2,500

Hand weeding, Propping, 

Orchard Maintenance 100 0.0015 14,000

Hand Harvesting 1,400 0.021 1,000

Transplanting 230 0.0035 6,300

Thinning 3,600 0.055 400

Greenhouse Tomatoes

Hand Harvesting, 

Pinching, Hand Pruning, 

Scouting, Turning, 

Tying, Hand Weeding, 

1200

1.01

0.018 1,200

Irrigation (Hand 

Watering), Transplanting 230 0.0035 6,300

1 DFR = Application Rate ×F ×(1-D)t ×4.54E8 μg/lb ×2.47E-8 acre/cm2; where F = 0.25 and D = 0.10 per day 

2 Daily Dermal Dose = [DFR (μg/cm2) × Transfer Coefficient × 0.001 mg/μg × 8 hrs/day × dermal absorption (%)]  BW (kg).

3 MOE = POD (mg/kg/day) / Daily Dermal Dose. Daily Dermal Dose = [DFR (μg/cm2) ×TC ×0.001 mg/μg ×8 hrs/day ×dermal 

absorption factor (%)]  BW (kg).
Page 52 of 53

Appendix F. International Residue Limits Status Sheet

Boscalid (128008); 02/21/2013)

Summary of US and International Tolerances and Maximum Residue Limits 

Residue Definition:

US Canada Mexico2 Codex3

40 CFR §180.589. Plant commodities:

boscalid, 3-pyridinecarboxamide, 

2-chloro- N -(4′-chloro[1,1'-

biphenyl]-2-yl),

Plant commodities:

2-chloro-N-(4'-

chloro[1,1'-

biphenyl]-2-yl)-3-

pyridinecarboxamide

- Plant commodities: 

boscalid. The residue is fat soluble.

Commodity1

Tolerance (ppm) /Maximum Residue Limit (ppm)

US Canada Mexico2

Codex3

Artichoke, globe 6.0 None None

Belgium endive

(witloof chicory)

6.0 None None

Persimmon 8.0 None None

Vegetable, bulb, group 3-07 5.0 5.0

Vegetable, fruiting, group 8-10 3.0 1.4 3.0

Fruit, citrus, group 10-10 2.0 2.0

Fruit, pome, group 11-10 3.0 3.0 2 (Apple)

Caneberry, subgroup 13-07A 10.0 6.0 10 (Berries and other small fruits)

Bushberry subgroup 13-07B 13.0 10 (Berries and other small fruits)

Fruit, small, vine climbing, except 

fuzzy kiwifruit, subgroup 13-07F

5.0 3.5 5 (Grapes)

Berry, low growing, subgroup 13-

07G except cranberry

4.5 4.5

Strawberry

11

Low bush 

blueberry

3 (Strawberry)

Oilseed group 20 5.0 5.0

Canola oil

Mustard seed 

oil

1

Vegetable, root, except sugar beet, 

subgroup 1B, except garden beet, 

radish, and turnip

2.0 0.7

Carrot

0.7

Rutabaga root

0.7

Burdock root

0.7 Ginseng 

root

0.7 

Horseradish

[1 sugar beet

1 turnip root

1 radish root]

2 (Root and tuber vegetables)

Turnip, tops 40 1.0 40 (Leafy vegetables)
Page 53 of 53

1

Includes only commodities of interest for this action. Tolerance values should be the HED recommendations and 

not those proposed by the applicant.

2 Mexico adopts US tolerances and/or Codex MRLs for its export purposes.

3 * = absent at the limit of quantitation; Po = postharvest treatment, such as treatment of stored grains. PoP = 

processed postharvest treated commodity, such as processing of treated stored wheat. (fat) = to be measured on the 

fat portion of the sample. MRLs indicated as proposed have not been finalized by the CCPR and the CAC.