AITC (in Oil of Mustard) DP Numbers: 406246 & 406248 PC Code: 051102 EPA File Symbol Nos.: 89285-R & -E Product chemistry, Tier I Tox, Non- Target Organisms Hazard Assessment

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY WASHINGTON, D.C. 20460

Office of Chemical Safety and Pollution Prevention

MEMORANDUM May 15, 2013

SUBJECT : Science Review in Support of the Re gistration of the TGAI/MP IR9804 and the EP, IRF 135, Respectively Containing 99.8% and 96.3% Allyl Isothiocyanate (AITC) As Their Active Ingredient. Th e TGAI/MP is an unregistered source of the active ingredient.

Decision No : 469288 & 469289
DP Nos.: 406246 & 406248 EPA Reg. Nos: 89285-R & -E
Chemical Class: Biochemical
CAS. No.: 57-06-7
PC Code: 004901 Tolerance Exemptions : 40 CFR 180.1167 (for AITC) in Oil of Mustard

MRID Nos. : 488241-01 to -08 & 489194-01 to -03

FROM: Russell S. Jones, Ph.D, Senior Biologist /S/ 05/15/2013
Biochemical Pesticides Branch Biopesticides & Pollution Pr evention Division (7511P)

TO: Gina Burnett, Regulatory Action Lead er /S/ 05/15/2013
Biochemical Pesticides Branch Biopesticides & Pollution Pr evention Division (7511P)

ACTION REQUESTED

On behalf of Isagro, A. Roberts (TSG) submitted a request for the registration of the TGAI/MP IR9804 and the EP, IRF 135, respectively cont aining 99.8% and 96.3% Allyl Isothiocyanate (AITC) as their active ingredient. The TGAI/MP is an unregistered source of the active ingredient. In support of the submission, the registrant has submitted Product Chemistry and Tier I Toxicity information and waivers for all Ti er I Non-Target Organism data requirements.

Under 40 CFR 180.1167 Allyl isothiocyanate is exem pt from the requirement of a tolerance for residues when used as a component of food grade oil of mustard, in or on all raw agricultural commodities, when applied according to approved la beling. The inert ingredient is cleared for
food use under 40 CFR 180.910.AITC (in Oil of Mustard) DP Numbers: 406246 & 406248 PC Code: 051102 EPA File Symbol Nos.: 89285-R & -E Product chemistry, Tier I Tox, Non- Target Organisms Hazard Assessment

The currently proposed label application methods are for pre-plant applications, which would be
considered a non-food use. No residual activit y is expected and the active ingredient will dissipate prior to crop seeding.

RECOMMENDATIONS AND CONCLUSIONS

1a. The Product Chemistry data submitted in support of the TGAI/MP, IR9804 (EPA File Symbol No. are 89285-R), are ACCEPTABLE.

1b. The Product Chemistry data submitted in support of the EP, IRF135 (EPA File Symbol No. are 89285-E), are ACCEPTABLE.

2a. The Tier I Toxicity studies, data, and wa iver rationales submitted in support of the TGAI/MP data requirements are ACCEPTABLE . No additional data are required.

2b. Tier I Toxicity information submitted in s upport of the TGAI/MP is bridged to support of the EP data requirements. ACCEPTABLE.

3. Waiver rationales submitted in support of the TGAI/MP Non-Target Organism data requirements are ACCEPTABLE.

STUDY SUMMARIES

I. Active Ingredient Characterization

Allyl isothiocyanate (AITC) is the major component of natural mustard oil. It is present also in cooked cabbage, horseradish, and black mustard see d. It is syntheticall y produced from allyl iodide and potassium thiocyanate

Product Names: TGAI/MP: IR9804 (99.8% a.i.) (EPA File Symbol No. 89285-R) EP: IRF135 (96.3% a.i.) (EPA File Symbol No. 89285-E)

Chemical Name: Allyl isothiocyanate Common Names: AITC, 3-Isothiocyanato-1-propene
PC Code: 070704

CAS No.: 56-06-7 Molecular Wgt.: 99.15
Chemical Formula: C 4 H 5 NS

See MRID 48824101, pp. 5 & 6, and Attachment 1 for additional details on IR9804. See MRID 48919401, pp. 5, and Attachment 1 for additional details on IRF135.AITC (in Oil of Mustard) DP Numbers: 406246 & 406248 PC Code: 051102 EPA File Symbol Nos.: 89285-R & -E Product chemistry, Tier I Tox, Non- Target Organisms Hazard Assessment

A. Product Chemistry (MRIDs 488241-01 & -02; 489194-01 & -02)

Data submitted to support the product chemistr y data requirements for the TGAI/MP (IR9804; EPA File Symbol No. 89285-R) ar e summarized in Table 1 below. Physical and chemical properties data are summarized in Table 2 be low. Refer to MRIDs 488241-01 and -02 for more
information.

TABLE 1. Product Chemistry Data Requirements for TGAI/MP IR9804 (9 9.8% AITC) (40 CFR § 158.2030) OPPTS Guideline No. Study Results MRID

830.1550

to
830.1670 Product identity; Manufacturing process;
Discussion of formation of unintentional ingredients Submitted data satisfy the requirements for product identity, manufacturing process, and discussion of formation of impurities.
ACCEPTABLE 48824101

830.1700 Analysis of samples Submitted data satisfy the requirements for analysis of samples.
ACCEPTABLE 48824102

830.1750 Certification of limits Limits listed in the CSF are

A CCEPTABLE -

830.1800 Analytical method ACCEPTABLE 48824102AITC (in Oil of Mustard) DP Numbers: 406246 & 406248 PC Code: 051102 EPA File Symbol Nos.: 89285-R & -E Product chemistry, Tier I Tox, Non- Target Organisms Hazard Assessment

TABLE 2. Physical and Chemical Pr operties of TGAI/MP IR9804 (99.8% AITC) (40 CFR § 158.2030)

OPPTS Guideline

No. Property Description of Result MRID
Method/Reference

830.6302 Color Colorless or pale yellow liquid 48824101 JECFA (2005) – see

Attachment 1 1 830.6303 Physical State Liquid 48824101 JECFA (2005) – see
Attachment 1 1

830.6304 Odor Very pungent, irritating aroma 48824101 JECFA (2005) – see
Attachment 1 1 830.6313 Stability to Normal and Elevated Temperatures, Metals and Metal Ions Reported stable. 48824101 EPA-HQ-OPP-2009- 0904 – Vegetable and Flower Oils Summary
Document for Registration Review –
March 2012 830.6315 Flammability Flashpoint = 46°C 48824101

International Chemical Safety Card, CDC/NIOSH (1997) – see
Attachment 1 830.6317 Storage Stability Study in progress – anticipated completion date is the last quarter of 2013. 48824101

Per method of analysis used in

OCSPP 830.1800. 830.6319 Miscibility Not Applicable; TGAI/MP is not an emulsifiable liquid and is not diluted with petroleum
solvents. -

830.6320 Corrosion Characteristics Study in progress – anticipated completion date is the last quarter of 2013. 48824101 Visual inspection of packaging materials during a one-year storage stability study. 830.7000 pH 4-5 pH meter 830.7050 UV/Visible Light Absorption Refractive index 1.524-1.531; seehttp://www.fao.org/ag/agn/jefcaflav/img/img/1560.gif for the absorbance spectrum 48824101 JECFA (2005) – see
Attachment 1 1

830.7100 Viscosity Not Applicable for TGAI/MP - 830.7200 Melting Point/Range -102.5 °C 48824101

International Chemical Safety Card, CDC/NIOSH (1997) – see
Attachment 1 830.7220 Boiling Point/Range
150-151°C

148-154°C 48824101 JECFA (2005) – see
Attachment 1 1

International Chemical Safety Card, CDC/NIOSH (1997) – seeAITC (in Oil of Mustard) DP Numbers: 406246 & 406248 PC Code: 051102 EPA File Symbol Nos.: 89285-R & -E Product chemistry, Tier I Tox, Non- Target Organisms Hazard Assessment

TABLE 2. Physical and Chemical Pr operties of TGAI/MP IR9804 (99.8% AITC) (40 CFR § 158.2030)

OPPTS Guideline

No. Property Description of Result MRID
Method/Reference

Attachment 1 830.7300 Density
1.013-1.020

1.0 48824101 JECFA (2005) – see
Attachment 1 1

International Chemical Safety Card, CDC/NIOSH (1997) – see
Attachment 1 830.7520 Particle Size, Fiber Length and
Diameter Distribution Not Applicable; TGAI/MP is
not fibrous -

830.7550
830.7560

830.7570 Partition Coefficient (n-Octanol/Water) Log P = 2.11 48824101 IARC Monograph
Volume 73 – see
Attachment 1 830.7840 Water Solubility Slightly soluble in water 48824101 JECFA (2005) – see
Attachment 1 1 830.7950 Vapor Pressure 1.33 kPa @ 38.3°C

0.493 kPa@ 20 °C 48824101 IARC Monograph
Volume 73 – see
Attachment 1

International Chemical Safety Card, CDC/NIOSH (1997) – see
Attachment 1

Classification: ACCEPTABLEAITC (in Oil of Mustard) DP Numbers: 406246 & 406248 PC Code: 051102 EPA File Symbol Nos.: 89285-R & -E Product chemistry, Tier I Tox, Non- Target Organisms Hazard Assessment

Data submitted to support the product chemistry data requirements for the EP (; EPA File Symbol No. 89285-E) are summarized in Table 3 below. Physical and chemical properties data
are summarized in Table 4 below. Refer to MRIDs 489194-01 and -02 for more information.

TABLE 3. Product Chemistry Data Requirements for EP IRF135 (9 6.3% AITC) (40 CFR § 158.2030)

OPPTS Guideline No. Study Results (below are example results) MRID
Method/Reference

830.1550

to
830.1670 Product identity; Manufacturing process;
Discussion of formation of unintentional ingredients Submitted data satisfy the requirements for product identity, manufacturing process, and discussion of formation of impurities.
ACCEPTABLE 489194-01

830.1700 Analysis of samples Not required for EP 489194-02

830.1750 Certification of limits Limits listed in the CSF are
ACCEPTABLE 489194-01

830.1800 Analytical method Not required for EP 489194-02AITC (in Oil of Mustard) DP Numbers: 406246 & 406248 PC Code: 051102 EPA File Symbol Nos.: 89285-R & -E Product chemistry, Tier I Tox, Non- Target Organisms Hazard Assessment

TABLE 4. Physical and Chemical Proper ties of EP IRF135 (96.3% AITC) (40 CFR § 158.2030)

OPPTS Guideline

No. Property Description of Result MRID

830.6302 Color Not applicable per 40 CFR 158.2030(e)

– P r oduct is an EP. -

830.6303 Physical State Liqui d 489194-01 Visual inspection at

room temperature
830.6304 Odor Not applicable per 40 CFR 158.2030(e)

– P r oduct is an EP. -

830.6313 Stability to Normal and Elevated Temperatures, Metals and Metal Ions Not ap p lica b le per 40 CFR 158.2030(e) – Product is an EP. -

830.6315 Flammability (flashpoint) 47oC 489194-02 Pensky-Martens

Closed Cup 830.6317 Storage Stability Study in progress

– anticipated completion date is the last quarter of
2013. 489194-01 Per method of analysis used in OCSPP 830.1800. 830.6319 Miscibility N ot ap p lica b le per 40 CFR 158.2030(e)(10) – EP is not an emulsifiable liquid and is not to be diluted with

p etroleum solvents. -

830.6320 Corrosion Characteristics Study in progress– anticipated completion date is the last quarter
of 2013. 489194-01 Visual inspection of packaging materials during a
one-year storage stability study. 830.7000 pH 4.87 (1% soln) 489194-02 pH meter 830.7050 UV/Visible Light Absorption N ot ap p lica b le per 40 CFR 158.2030(e) – Product is an
EP. -

830.7100 Viscosity 0.6 centistokes @ 40°C 0.8 centistokes @ 20°C 489194-02
ASTM D445/D446
Test Methods and

OPPTS 830.7100 830.7200 Melting Point/Range N ot ap p lica b le per 40 CFR 158.2030(e) – Product is an
EP. -

830.7220 Boiling Point/Range N ot ap p lica b le per 40 CFR 158.2030(e) – Product is an
EP. -

830.7300 Density 1.019 g/mL @ 20°C 489194-02 CIPAC MT-3, ASTM D891-95,
OPPTS 830.7300
and OECD TG 109 830.7520 Particle Size, Fiber Length and
Diameter Distribution N ot ap p lica b le per 40 CFR 158.2030(e) – Product is an
EP. -

830.7550
830.7560

830.7570 Partition Coefficient (nOctanol/Water) N ot ap p lica b le per 40 CFR 158.2030(e) – Product is an
EP. -

830.7840 Water Solubility N ot ap p lica b le per 40 CFR 158.2030 ( e )

– P r oduct is an -AITC (in Oil of Mustard) DP Numbers: 406246 & 406248 PC Code: 051102 EPA File Symbol Nos.: 89285-R & -E Product chemistry, Tier I Tox, Non- Target Organisms Hazard Assessment

TABLE 4. Physical and Chemical Proper ties of EP IRF135 (96.3% AITC) (40 CFR § 158.2030)

OPPTS Guideline

No. Property Description of Result MRID

EP. 830.7950 Vapor Pressure N ot ap p lica b le per 40 CFR 158.2030(e) – Product is an
EP. -

Classification: ACCEPTABLE

II. Human Health Assessment

A. Toxicology for TGAI/MP (MRID 48824108)

The data presented in Table 5 below are a su mmary of the toxicity data and information submitted to support the TGAI/MP . Refer to the DERs for more information.

Table 5. Mammalian Toxicology Data Requirements for TGAI/MP AITC (40 CFR § 158.2050)

Study/OPPTS Guideline No. Results Toxicity Category/Description MRID

Acute oral toxicity (rat) (870.1100) LD 50 = 425.4 mg/kg
ACCEPTABLE II 488241-03

Acute dermal toxicity (rat) (870.1200) LD 50 > 200 mg/kg
ACCEPTABLE II 488241-04

Acute inhalation toxicity (rat) (870.1300) LC 50 > 0.21 mg/L
ACCEPTABLE II 488241-05

Primary eye irritation (rabbit) (870.2400) Waiver due to observed corrosiveness on skin
ACCEPTABLE I 1

Primary dermal irritation (rabbit) (870.2500) Corrosive
ACCEPTABLE I 488241-06

Dermal sensitization (guinea pig) (870.2600) Sensitizer
ACCEPTABLE - 488241-07

Hypersensitivity incidents (885.3400) - - -

90-Day oral toxicity (870.3100) Rationale submitted
ACCEPTABLE 488241-08

90-Day dermal toxicity (870.3250) Rationale submitted
ACCEPTABLE 488241-08

90-Day inhalation toxicity (870.3465) Rationale submitted
ACCEPTABLE 488241-08

Mutagenicity (870.5100, 5300 and 5375) Rationale submitted
ACCEPTABLE 488241-08

Developmental toxicity (870.3700) Rationale submitted
ACCEPTABLE 488241-08AITC (in Oil of Mustard) DP Numbers: 406246 & 406248 PC Code: 051102 EPA File Symbol Nos.: 89285-R & -E Product chemistry, Tier I Tox, Non- Target Organisms Hazard Assessment

1. Acute Toxicity for the TGAI/MP IR 9804 (99.8%; EPA File Symbol No. 89285-R)

The AITC technical (EPA Reg. No. 89285-R; 99.8% a.i. ) is in Toxicity Category II for acute oral toxicity, acute dermal toxicity, and acute inhala tion toxicity. It is in Toxicity Category I for primary eye irritation and primary dermal irritati on due to its corrosivity. No hypersensitivity incidents have been reported.

NOTE : All references cited in th e following discussions of th e rationales submitted in support of the Tier I data requirements may be found in the respective sections of MRID 48824108. Similarly, more detailed di scussions of Methods and Materials used in the cited studies may be found in MRID 48824108 or in the cited studies themselves.

2. Subchronic Toxicity

90-Day Oral Toxicity in Rodents (OCSPP 870.3100): A Guideline 90-day oral toxicity study was not submitted. In lieu of a study, the appl icant submitted a rationale to support the data requirement. The rationale is based on the following:

a. A 90-day oral toxicity study conducted by th e National Toxicology Program (NTP, 1982) on F344/N rats dosed with 1.5 to 25 mg AITC /kg-body wgt/day, five days per week for 13
weeks had a No Observed Adverse Effect Level (NOAEL) of 25 mg AITC/kg-body wgt/day, the highest level tested. No mortalities o ccurred during the course of the study and no
treatment-related effects were observed on ti ssues obtained from the test animals when compared to non-treated controls. There were no differences in body weights between
treated animals and non- treated controls.

b. Humans are regularly exposed to AITC in th e diet, and to sinigri n, a precursor to AITC, which is converted to AITC by the enzyme, my rosinase, upon disruption of cells. AITC and sinigrin are present at relati vely high levels in cauliflowe r, kale, horseradish, wasabi, and mustard. For example, Wasabi contains up to 34 umol of sinigrin/AITC per gram and brown mustard has been shown to contain approxima tely 0.453 mg AITC per gram. The official serving size of Grey Poupon Dijon mustard (according to th e product label) is one teaspoon, which is equal to 5 grams, equivalent to 2.27 mg AITC/serving (Bha ttacharya et al., 2010; Jiao et al., 1994; & Zhang, 2010).

c Oral exposure to AITC when used as a soil-a pplied pesticide is not expected to increase above normal dietary exposure in foods due to the rapid degradation of AITC in soil and water. AITC degradation in soil has been repo rted to be rapid with a half-life ranging from 20 to 60 hours, with a mean half-life of 47 hours (+ 27) in six differe nt soil types. Degradation is greatest in soils with high or ganic matter (OM) and tota l nitrogen (N) content, and increases with increasing temperature. Up to 97.1% AITC degrades within 10 days at 20

o C in high OM and N soils (Borek et al., 1995; & Pechacek et al., 1997).

d. The primary degradation products of AITC in mo ist soils are likely to be allyl thiocyanate (ATC), allylamine (AA), and carbon disulfide, (CDS) based on experiments using AITC inAITC (in Oil of Mustard) DP Numbers: 406246 & 406248 PC Code: 051102 EPA File Symbol Nos.: 89285-R & -E Product chemistry, Tier I Tox, Non- Target Organisms Hazard Assessment

aqueous solution at varying temperatures (20-80 o C for 80 minutes) and pH levels pH 6-8). ATC, an isomer of AITC, was identified at each pH level tested and is expected to degrade as rapidly as AITC. Likewise, the chemically sim ilar AA, if it is formed, is expected to degrade quickly. CDS is already present in the enviro nment and is released to terrestrial soils via exudates from tree roots, and is present in ti dal marshes. Increased oral exposure to AITC degradates via application of AITC to soils is unlikely based on na tural occurrence and the environmental fate of these compoun ds (HSDB, 2012; & Pechacek et al., 1997).

e. In addition, the Agency notes that the proposed end-use product is intended for use as a preplant soil treatment . The produc t label specifies that the soil applied product be permitted to completely dissipate from the treated soil prio r to the planting of any crop (as determined by lettuce seed and/or tomato/pepper transplant bioassays. The presence of residues on edible commodities, as well as oral dietary e xposure to AITC are highly unlikely.

CLASSIFICATION: ACCEPTABLE

90-Day Dermal Toxicity (OCSPP 870.3250): A Guideline 90-day dermal toxicity study was
not submitted. In lieu of a study, the applicant submitted a ra tionale to support the data requirement. The rationale is based on the following:

a. The proposed end-use product is intended for use as a pre-plant soil treatment.

b. The product is not intended fo r application to human skin.

c. Prolonged or repeated dermal contact is not expected when the EP is applied in accordance
with label use direct ions. The application methods are: (i) tractor mounted shank injection at a depth of 8 to 15 inches, followed by tarp overlay, (ii) by drip inje ction, also covered by tarp overlay, and (iii) by deep injection to depths greater than 17 inches, with no tarp covering. These application methods mi nimize the potential for dermal exposure.

d. In addition, the Agency notes that the product labe l specifies a 48-hour re-entry interval unless wearing appropriate PPE (coveralls, prot ective eyewear, chemical resistant gloves, and footwear plus socks). Repeated dermal exposure to the pre-plan t soil applied end-use product is highly unlikely.

CLASSIFICATION: ACCEPTABLE

90-Day Inhalation Toxicity (OCSPP 870.3465): A Guideline 90-day dermal toxicity study was not submitted. In lieu of a study, the appl icant submitted a rationale to support the data requirement. The rationale is based on the following:

a. Repeated inhalation exposure to AITC aeros ol, vapor or gas is highly unlikely and not expected, when the EP is applied in accordan ce with label use direc tions. The application methods are: (i) by tractor mounted shank inj ection at a depth of 8 to 15 inches, followed byAITC (in Oil of Mustard) DP Numbers: 406246 & 406248 PC Code: 051102 EPA File Symbol Nos.: 89285-R & -E Product chemistry, Tier I Tox, Non- Target Organisms Hazard Assessment

tarp overlay, (ii) by drip injection, also covere d by tarp overlay, and 3) by deep injection to depths greater than 17 inches, with no tarp covering. These application methods minimize the potential for inhalation exposure.

b. AITC degrades readily in soil and water and, th erefore, inhalation expo sure is highly unlikely to occur after the tarps ar e removed following treatment (Borek et al., 1995; Pechá č ek et al., 1997). AITC degrades rapidly in the soil with a short half-life (T1⁄2) ranging from 20 to 60 hours (Borek et al., 1995). The average T1⁄2 of AITC in six different soil types was reported to be 47 ± 27 hours, with the greatest degrad ation rate of in soils that have high organic carbon and total nitrogen (N) content. In a ddition, the AITC T1⁄2 in soil increases with increasing moisture content and decreases in soil with increasing temperature between 10 o C
and 25 o C. During the first 24 hours, an averag e of 29.8% of AITC was transformed, or degraded, and over the first 10 days at 20 o C, an average of 97.1% was degraded (Borek et al., 1995). The data also demonstrate that AITC tran sforms in sterilized soil at the same rate as intact soil, indicating that microbial populations are not re sponsible for the degradation (Borek et al., 1995). The more rapid degrada tion that occurs in soil with higher levels of organic carbon suggests that AI TC reacts with the organic mate rial and is inactivated. The rapid degradation of AITC in treated soil suggests that inhalation exposure will be highly unlikely following pre-plant soil treatments in accordance with label use directions.

c. The metabolism of AITC has been described in evaluations of food and fo od additives, and is not expected to be any different following i nhalation exposure than following oral exposure.
AITC is metabolized in humans by conjugation with glutathione and this conjugate is further metabolized to mercapturic acid s that are eliminated via the urine (Shapiro et al., 1998). The available data suggest that AITC is metabolized via the sa me pathways regardless of the route of exposure.

d. Based on the information discussed above in paragraph “c,” acute and subchronic oral toxicity data may be used to characterize the potential risk from inhalation exposure to AITC. A 90-Day Oral Toxicity study w ith AITC that provided a no-observed-adverse- effect-level (NOAEL) of 25 mg/kg/day has been conducted (NTP, 1982). AITC was administered to rats by gavage at doses of 0, 1.5, 3, 6, 12, and 25 mg/kg/day for 13-weeks. Any AITC inhalation exposure identified may be compared to an acceptable exposure level identified based on the NOAEL from this study.

CLASSIFICATION: ACCEPTABLE

3. Developmental Toxicity (OCSPP 870.3700): A Guideline Prenatal Developmental Toxicity study was not submitted. In lieu of a study, the applicant submitted a rationale to support the data requirement. The rationale is based on the following:

a. Allyl Isothiocyanate (AITC) was one of 16 chemically-related compounds evaluated in a study designed to correlate pot ential developmental toxicity with molecular structure (Ruddick et al., 1976). In this study, a single dose of AITC was administered to pregnant dams at 60 mg/kg or 120 mg/kg by gavage on da y 12 or 13 of gestation and the dams wereAITC (in Oil of Mustard) DP Numbers: 406246 & 406248 PC Code: 051102 EPA File Symbol Nos.: 89285-R & -E Product chemistry, Tier I Tox, Non- Target Organisms Hazard Assessment

sacrificed on day 22 and examined for individu al litter weight, litte r size, and number of deciduomas and corpora lutea. Control animals we re administered equivalent doses of either water or corn oil. The results were comp ared against pregnant dams dosed with the suspected teratogen, ethylenethiourea (ETU ). The higher dose was close to the LD 50 for AITC, so only results at the lo wer dose were used. No diffe rence in the percentage of abnormal fetuses in AITC-treated offspring we re detected compared to control, and no
difference between treated and control in the % dead fetuses was detected. The authors
concluded that AITC did not di splay any teratogenic potential at the NOAEL of 60 mg/kg. The 60 mg/kg dose would be equivalent to 4.2 g AITC for a standard 70 kg human.

b. Human dietary exposure to AITC is common due to natural occurr ence of AITC in many foods. Many vegetables contain AITC or produc e the precursor to AITC, sinigrin, which is converted by the enzyme myrosinase to AITC upon disruption of the cells (Bhattacharya et al., 2010; Zhang, 2010) and upon exposure to moisture . Sinigrin and/ or AITC levels are typically high in cauliflower, kale, horseradis h, wasabi and mustard. Wasabi may contain up

to 34 μ mol sinigrin / AITC per gram (Zhang 2010) , whereas brown mustard has been shown to contain approximately 0.453 mg of AITC per gram, such that a 10 gram serving contains 4.53 mg of AITC (Jiao et al., 1994 ). The official serving size for Grey Poupon Dijon mustard identified on the label is one teaspoon, which is equal to 5 grams (2.27 g AITC equivalent or 0.54x of the NOAEL)

c. See discussion under part “b.” of the 90-day Inhalation rationale above . In addition, possible degradation products of AITC in soil can be proposed based on the decomposition products of AITC present in an aqueous solution in the pH range between 6 and 8, where AITC is proposed to degrade completely (Pechá č ek et al., 1997). Within this pH range, Pechá č ek et al. (1997) observed that the primary decomposition products identified at 80 o C and in lower quantities at 20 o C and 40 o C after an 80 min incubation, we re: allyl thiocy anate (ATC); allylamine (AA); and carbon disulfide (CDS). ATC, an isomer of AITC, was identified at each pH and sampling interval; AA is expected to biodegrade quickly in the environment, and so if it is formed following AITC treat ment of soil, human and animal exposure is unlikely (HSDB). CDS is naturally occurring in the environment, and is released from tree roots, tidal marshes and soil (HSDB). CDS is c onsidered ubiquitous in the environment, and so formation of carbon disulfide from treating soil with AITC woul d not increase exposure over levels currently in the environment (HSDB, accessed 8/2012).

d. Application methods together with appropr iate PPE will mitigate human exposure. The application methods are: (i) by tractor mounted shank injection at a depth of 8 to 15 inches, followed by tarp overlay, (ii) by drip injection, also covered by tarp overlay, and 3) by deep injection to depths greater than 17 inches, w ith no tarp covering. These application methods minimize the potential for inhalation exposure.

Human exposure to the primary degradates of AITC identified in aqueous solutions following soil treatment in the environment appears unlikely based on the natural occurrence and environmental fate of these compounds, as well as the methods of application

CLASSIFICATION: ACCEPTABLEAITC (in Oil of Mustard) DP Numbers: 406246 & 406248 PC Code: 051102 EPA File Symbol Nos.: 89285-R & -E Product chemistry, Tier I Tox, Non- Target Organisms Hazard Assessment

4. Mutagenicity (OCSPP 870.5100; 870.5300; & 870.5375): Guideline Mutagenicity studies were not submitted. In lieu of a study, the appl icant submitted a rationale to support the data requirements. The rationale is based on the following:

a. The National Toxicology Program (NTP) has conducted a battery of mutagenicity studies (NTP, 1981, 1988, & 1991) on AITC, including a B acterial Reverse Mutation Assay using S. typhimurium strains TA100, TA1535, and TA99 with and without S9 activation; and In

Vitro Mammalian Gene Mutation Test using mous e lymphoma L5178Y TK+/- cells; and an

In Vivo Mammalian Chromosome Aberration Test.

b. Two reverse mutation studies (NTP, 1981) conf irmed that mutagenicity responses were negative in all strain s tested with and w ithout S9 activation.

c. Three in vitro mammalian gene mutation studies were conducted using mouse lymphoma cells without S9 activation (NTP, 1988). A nega tive response was observed in the first trial using mouse lymphoma cells without S9 activa tion at concentrations ranging from 0.05 to 0.8 mg/mL AITC. A second trial without S9 ex hibited a significant increase in average mutant frequency and significant re duction in relative total growth at AITC concentrations of 0.4, 0.6, and 0.8 mg/mL; 1.0 mg/mL was cytotoxic. A third trial without S9 also exhibited a significant increase in average mutant frequenc y at concentrations of 0.6 to 1.4 mg/mL and a significant reduction in growth; a concentration of 1.6 mg/mL was cytotoxic. It is noted that the positive results were observed without S9 activation and in the pr esence of substantial cytotoxicity.

d. An in vivo mammalian chromosome aberration study (NTP, 1991) was conducted with mice dosed intraperitoneally with 0, 25, or 50 mg/kg AITC and compared against mice dosed with a positive control, dimethylben zanthracine (DMBA). Increases in chromosome aberrations
were not observed in AITC treated mice when compared to non-treated (negative) controls, while a positive response was observed in DMBA-treated mice.

e. The weight of evidence demonstrates that AITC is not likely to be a mutagen. In addition, the method of application and rapid degrada tion rate, together w ith appropriate PPE, mitigates exposure to humans.

CLASSIFICATION: ACCEPTABLE

B. Toxicology for EP (MRID 488919103)

Guideline studies for acute toxicity testing were not submitted. In lieu of Guideline studies, the registrant submitted a request to bridge the acu te toxicity data subm itted in support of the TGAI/MP (containing 99.8% AITC) to support the acu te toxicity data requirements for the EP (containing 96.5% AITC) which also contains 3.5% (w/w) of a well known surfactant approved for formulation with food use pesticides under 40 CFR 180.910.AITC (in Oil of Mustard) DP Numbers: 406246 & 406248 PC Code: 051102 EPA File Symbol Nos.: 89285-R & -E Product chemistry, Tier I Tox, Non- Target Organisms Hazard Assessment

Conclusions: The concentration of AITC is slightly lower in the EP (96.5%) than in the TGAI/MP (99.8%). Furthermore, the inclusion of a relatively small amount of a well known surfactant (3.5% of product, w/ w) that is already approved for food use (under 40 CFR 180.910), is not expected to change the toxicity profile. The bridging of acute toxicity data submitted in support of the TGAI/MP registration to support the registration of th e EP, is acceptable.

CLASSIFICATION: ACCEPTABLE

III. Nontarget Organism Assessment (MRID 48824108)

The data presented in Table 6 below are a summary of the nontarget organism toxicity data and information submitted to support of the TGAI/MP. Refer to the appropr iate pages in MRID 48844108 for more detailed information and specifi c reference citations from the scientific
literature. .

Table 6. Non-Target Organism Data Requirements for TGAI/MP AITC (40 CFR § 158.2060)

Study/OPPTS Guideline No. Results Toxicity Category/Description MRID

Avian Acute Oral/OPPTS
850.2100 Rationale submitted
ACCEPTABLE No acute oral exposure based on application method and rapid environmental degradation 48824108, p. 18

Avian Dietary/OPPTS 850.2200 Rationale submitted
ACCEPTABLE No dietary exposure based on application method and rapid

environmental degradation 48824108, p. 20

Freshwater Fish LC50/OPPTS
850.1075 Rationale submitted
96-hr LC 50 = 0.077 ppm
ACCEPTABLE Very Highly Toxic, but no aquatic exposure based on application method and rapid

environmental degradation 48824108, pp. 22,

37-47

Freshwater Invertebrate/OPPTS
850.1010 Rationale submitted
48-hr EC 50 = 0.73 ppm
ACCEPTABLE Very Highly Toxic, but no aquatic exposure based on application method and rapid

environmental degradation 48824108, pp. 23,

216-221

Non-target Plants/OPPTS
850.4100 & 4150 Rationale submitted
ACCEPTABLE No non-target exposure based on application method and rapid environmental degradation 48824108, pp. 24-
27

Non-target Insects Rationale submitted
ACCEPTABLE No non-target exposure based on application method and rapid environmental degradation 48824108, pp. 28,

29

SUMMARY:

Guideline studies were not submitted in support of the non-target organism data requirements. In lieu of Guideline studies, the applicant submitted rationales, on a Guideline-by-Guideline basis, for each non-target organism data requi rement, which were supported both by scientificAITC (in Oil of Mustard) DP Numbers: 406246 & 406248 PC Code: 051102 EPA File Symbol Nos.: 89285-R & -E Product chemistry, Tier I Tox, Non- Target Organisms Hazard Assessment

literature citations as well as an argument for a lack of exposure to non-target organisms to AITC based on its rapid degradation in soil, its widespread presence in commonly eaten foods, as well as by the methods and timing of application of the EP.

AITC degrades readily in soil and water and, ther efore, inhalation exposure is highly unlikely to occur after the tarps are removed follow ing treatment (Borek et al., 1995; Pechá č ek et al., 1997). AITC degrades rapidly in the soil with a shor t half-life (T1⁄2) ranging fr om 20 to 60 hours (Borek et al., 1995). The average T1⁄2 of AITC in six different soil type s was reported to be 47 ± 27 hours, with the greatest degradation rate of in soils that have high organic carbon and total nitrogen (N) content. In a ddition, the AITC T1⁄2 in soil increases with increasing moisture
content and decreases in soil with increasing temperature between 10 o C and 25 o C. During the first 24 hours, an average of 29.8% of AITC was transformed, or degraded, and over the first 10 days at 20 o C, an average of 97.1% was degraded (Borek et al., 1995). The data also demonstrate
that AITC transforms in sterilized soil at the same rate as intact soil, indicating that microbial populations are not responsible fo r the degradation (Borek et al., 1995). The more rapid degradation that occurs in soil with higher levels of organic carbon suggests that AITC reacts with the organic material and is inactivated. The rapid degradation of AITC in treated soil suggests that inhalation exposure will be highly unlikely following pre-plant soil treatments in
accordance with label use directions.

In addition, possible degradation products of AITC in soil can be proposed based on the decomposition products of AITC present in an aq ueous solution in the pH range between 6 and 8, where AITC is proposed to degrade completely (Pechá č ek et al., 1997). Within this pH range,
Pechá č ek et al. (1997) observed that the prim ary decomposition products identified at 80 o C and in lower quantities at 20 o C and 40 o C after an 80 min incubation, we re: allyl thiocy anate (ATC); allylamine (AA); and carbon disulfide (CDS). ATC, an isomer of AITC, was identified at each pH and sampling interval; AA is expected to biodeg rade quickly in the environment, and so if it is formed following AITC treatment of soil, hum an and animal exposure is unlikely (HSDB). CDS is naturally occurring in the environment, a nd is released from tree roots, tidal marshes and soil (HSDB). CDS is considered ubiquitous in the environment, and so formation of carbon disulfide from treating soil with AITC would not increase exposure to non-target organisms over levels currently in the environment (HSDB, accessed 8/2012).

IRF135 is an end-use product (EP) formulated from IR9804, which is a technical grade active ingredient (TGAI/MP) containing 99.8% allyl is othiocyanate (AITC). IRF135 is approximately
96.5% AITC and 3.5% of a well known surfacta nt approved for food use under 40 CFR

180.910. IRF 135 is intended for use in an as a pre-pl ant soil treatment to control and repel fungi, insects, nematodes and weeds. AITC is a component of many common cruciferous vegetables including broccoli and Brussels sprouts, and is particularly concentrated in mustard seed, horseradish, and wasabi.

Application methods together with appropria te PPE will mitigate human exposure. The application methods are: (i) by tractor mounted shank injection at a depth of 8 to 15 inches, followed by tarp overlay, (ii) by drip injection, al so covered by tarp overlay, and 3) by deep injection to depths greater than 17 inches, with no tarp coveri ng. These application methods minimize the potential for exposur e to non-target organisms.AITC (in Oil of Mustard) DP Numbers: 406246 & 406248 PC Code: 051102 EPA File Symbol Nos.: 89285-R & -E Product chemistry, Tier I Tox, Non- Target Organisms Hazard Assessment

CLASSIFICATION: ACCEPTABLE