Document ID: EPA-HQ-OPP-2007-0416-0006
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2008-07-09T04:00Z

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON, D.C.  20460

OFFICE OF           

PREVENTION, PESTICIDES

AND TOXIC SUBSTANCES

MEMORANDUM

Date:		3/12/08

Subject:		Azoxystrobin.  Petitions for the Establishment of Permanent
Tolerances for New/Amended Uses on Non-grass Animal Feeds (Crop Group
18), Sorghum, Wheat, Cotton and Wild Rice.  PP#s6F7106 & 7F7198. 
Summary of Analytical Chemistry and Residue Data.

DP#s:	334571 and 340016	Decision #s:	370691 and 377487

PC Code:	128810	MRID Nos.:	46924301 -03, 47096401-02

40 CFR §180.	507

Chemical Class:	Strobilurin Fungicide

From:		W. Cutchin, Chemist

Alternative Risk Integration Assessment Team (ARIA)

Risk Integration Minor Use and Emergency Response Branch (RIMUERB)

Registration Division (RD; 7505P)

Through:	S. Hummel, Senior Chemist

		Registration Action Branch 3 (RAB3)

		Health Effects Division (HED; 7509P)

To:		S. Piper, Chemist

ARIA/RIMUERB/RD (7505P)

	And

T. Kish/J. Bazuin. PM 22

RD (7505P)

This document was originally prepared under contract by Dynamac
Corporation (2275 Research Blvd, Suite 300; Rockville, MD 20850;
submitted 09/24/2007).  The document has been reviewed and revised to
reflect current Office of Pesticide Programs (OPP) policies.

Executive Summary

called β-methoxyacrylates, which are derived from the naturally
occurring strobilurins.  Its biochemical mode of action is inhibition of
electron transport.  The fungicide is currently registered for use on a
variety of field, vegetable, fruit, and nut crops as well as on
ornamental plants and turfs.  End-use products of azoxystrobin are
typically formulated as water dispersible granular (WDG) and flowable
concentrate (FlC) formulations.  These products may be applied as
in-furrow at planting or postemergence foliar applications using ground
or aerial equipment at maximum seasonal rates of 0.40-2.0 lb ai/A. 
Azoxystrobin is also registered for seed treatment of many food/feed
crops as well as for postharvest uses of banana/plantains and citrus
fruits.

  SEQ CHAPTER \h \r 1 Azoxystrobin tolerances have been established in
40 CFR §180.507.  Tolerances for plant commodities are listed in 40 CFR
§180.507(a)(1) and are expressed in terms of residues of the fungicide,
azoxystrobin and the Z-isomer of azoxystrobin.  The established
tolerances for plant commodities range from 0.01 ppm in/on pecans to 260
ppm in/on herb subgroup 10A, dried leaves.  Tolerances are currently
established for aspirated grain fractions (10 and 30 ppm); wheat grain
(0.10 ppm), hay (15 ppm) and straw (4 ppm); cotton gin byproducts (0.02
ppm) and undelinted seed (0.02 ppm); and rice grain (5 ppm), hulls (20
ppm) and straw (12 ppm).  Time-limited tolerances are also established
under 40 CFR §180.507(b) for the combined residues of azoxystrobin and
the Z-isomer of azoxystrobin in connection with use of the pesticide
under Section 18 emergency exemptions for Brassica, head and stem
subgroup 5A (30 ppm; expired 12/31/06 but a permanent tolerance has been
established under 40 CFR §180.507(1)(a)), wild rice (5 ppm; expires
12/31/09), and safflower seed (1 ppm; expires 6/30/08).

Tolerances for animal commodities are listed in 40 CFR §180.507(a)(2)
and are expressed in terms of residues of the azoxystrobin per se.  The
established tolerances for livestock commodities range from 0.006 (milk)
to 0.07 (meat byproducts) ppm; no tolerances are currently established
for poultry commodities.

This document addresses the adequacy of submitted and available residue
chemistry data submitted by Syngenta Crop Protection, Inc. under two
separate tolerance petitions, PP#6F7106 and PP#7F7198.

Under PP#6F7106, the petitioner requests the establishment of permanent
tolerances for residues of azoxystrobin (methyl
(E)-2-{2-[6-(2-cyanophenoxy)pyrimidin-4-yloxy]phenyl}-3-methoxyacrylate)
and the Z-isomer of azoxystrobin, (methyl
(Z)-2-{2-[6-(2-cyanophenoxy)pyrimidin-4-yloxy]phenyl}-3-methoxyacrylate)
in/on the following raw agricultural commodities:

Aspirated grain fractions	112 ppm

Barley, forage	30 ppm

Non-grass Animal Feeds - forage	35 ppm

Non-grass Animal Feeds - hay	100 ppm

Sorghum - forage	25 ppm

Sorghum - grain	9 ppm

Sorghum - stover	40 ppm

Wheat - forage	30 ppm

In addition, to account for the potential increase in dietary exposure
resulting from the proposed new and/or amended uses described above,
Syngenta also requests that the tolerances currently established under
40 CFR §180.507(a)(2) for animal commodities, expressed in terms of
residues of azoxystrobin per se, be amended as listed below:

Cattle, fat	0.13 ppm

Cattle, kidney	1.00 ppm

Cattle, liver	5.10 ppm

Cattle, meat	0.07 ppm

Cattle, meat byproducts (except liver and kidney)	0.07 ppm

Goat, fat	0.13 ppm

Goat, kidney	1.00 ppm

Goat, liver	5.10 ppm

Goat, meat	0.07 ppm

Goat, meat byproducts (except liver and kidney)	0.07 ppm

Egg white	0.01 ppm

Egg yolk	0.15 ppm

Hog, fat	1.10 ppm

Hog, kidney	0.03 ppm

Hog, liver	0.23 ppm

Hog, meat	0.01 ppm

Hog, meat byproducts (except liver and kidney)	0.01 ppm

Horse, kidney	1.00 ppm

Horse, liver	5.10 ppm

Horse, meat	0.07 ppm

Horse, meat byproducts 	0.07 ppm

Milk	0.05 ppm

Poultry, fat	0.01 ppm

Poultry, liver	0.12 ppm

Poultry, meat	0.02 ppm

Sheep, fat	0.13 ppm

Sheep, kidney	1.00 ppm

Sheep, liver	5.10 ppm

Sheep, meat	0.07 ppm

Sheep, meat byproducts (except liver and kidney)	0.07 ppm

In another petition, PP#7F7198, Syngenta requests the establishment of
permanent tolerances for the residues of azoxystrobin and the Z-isomer
of azoxystrobin in/on the raw agricultural commodities listed below:

Cotton, undelinted seed	0.7 ppm

Cotton, gin byproducts	35 ppm

Wild rice	5.0 ppm

Concurrently, Syngenta wishes to amend the product label for Abound®
Flowable Fungicide (EPA Reg. No. 100-1098), an FlC formulation
containing 22.9% ai (2.08 lb/gal) azoxystrobin, and Heritage® Fungicide
(EPA Reg. No. 100-1093), a WDG formulation containing 50% ai (0.5
lb/gal) azoxystrobin to add new foliar uses on non-grass animal feeds
group and sorghum, and to amend the use directions for barley, rice
(adding wild rice), wheat/triticale and cotton.  Foliar applications are
to be made at maximum seasonal rates of 0.40 lb ai/A for barley and
wheat, 0.45 lb ai/A for cotton, or 0.70-0.75 lb ai/A for clover,
nongrass animal feeds, rice (including wild rice), and sorghum. 
Applications may be made using ground or aerial equipment.  The proposed
preharvest intervals range from 14 days (forage and hay; and sorghum
matrices) to 28-45 days (mature crop commodities).  

The nature of the residue in plants, rotational crops, and animals is
adequately understood.  Acceptable metabolism studies have been
conducted on primary crops of grapes, peanuts, and wheat as well as on
representative rotational crops.  Acceptable metabolism studies on goats
and laying hens are also available.  The residues of concern in/on
plants and rotational crops, for the tolerance expression and risk
assessment purposes, are azoxystrobin and its Z-isomer.  The residue of
concern in livestock is parent azoxystrobin only.

There are adequate residue analytical methods for tolerance enforcement.
 For analysis of plant commodities for residues of azoxystrobin and its
Z-isomer, a gas chromatography with nitrogen phosphorus detector
(GC/NPD) method (RAM 243/04) has undergone method validation by the
Analytical Chemistry Branch (ACB/BEAD).  BEAD comments have been
incorporated, and the revised method (designated RAM 243, dated 5/15/98)
has been submitted to FDA for inclusion in PAM, Volume II.  For analysis
of animal commodities for residues of azoxystrobin per se, a GC/NPD
method (RAM 255/01) has been validated by an independent laboratory for
the analysis of milk, liver and eggs, and by the EPA analytical
laboratory for the analysis of milk and liver.  The EPA laboratory
written report (with an EPA addendum to accompany the method) and the
method will be submitted to FDA for inclusion in PAM, Volume II.

For analysis of samples from the crop field trial and processing studies
associated with the current petitions, a high performance liquid
chromatography coupled to a triple quadrupole mass spectrometer
(LC/MS/MS) method, RAM 305/03, was used as the data-collection method. 
RAM 305/03 was adequately validated at fortification levels ranging from
of 0.01 to 7.5 ppm.  The requirements for multiresidue methods testing
data for azoxystrobin are fulfilled.  The available data indicate that
azoxystrobin could not be recovered through application of the
multiresidue protocols.

Previously submitted storage stability data indicate that residues of
azoxystrobin and the Z-isomer are reasonably stable for at least two
years under frozen storage in/on the following commodities:  apples,
bananas, carrot, cucumbers, grapes, leaf lettuce, oil seed rape,
peaches, winter wheat straw, wheat forage, wine, peanut oil and meal,
tomato juice and paste, soybean meal, corn grits, and orange oil, juice
and pulp.  These data are adequate for the purpose of supporting the
proposed tolerances.  

Adequate cattle and poultry feeding studies are available to support the
livestock dietary burdens resulting from the proposed uses.  Dietary
burdens were calculated reflecting the most recent guidance concerning
revisions of feedstuff percentages and reasonably balanced livestock
diets were constructed.  Reassessment of tolerances indicates that no
increases in the existing tolerances for milk and fat, meat and meat by
products of ruminants and swine are necessary.  The proposed and amended
uses of azoxystrobin on the poultry feed items are not expected to alter
the Agency’s previous conclusion that there is no reasonable
expectation of finite residues in poultry commodities.  No tolerances
are needed for poultry and eggs.  

The submitted field trial data for alfalfa and clover, the
representative crops of nongrass animal feeds, crop group 18, are
adequate.  A revised Section F is required at 45 ppm for forage and 120
ppm for hay of the nongrass animal feeds crop group 18.  

Although geographical representation is adequate, the submitted residue
data for sorghum are not adequate because they do not fully reflect the
proposed use patterns.  The residue data only reflect the proposed use
pattern for postemergence foliar applications and did not reflect the
in-furrow treatment.  The available data may be used for a conditional
registration.  Unconditional registration may be granted pending
submission of residue data from four bridging sorghum field trials which
must be conducted in Zones 5 (2 trials), 6 (1 trial), and 8 (1 trial). 
The petitioner may also remove this condition of registration by
deleting the in-furrow use from the label.

The field trial data for sorghum forage, grain, and stover indicate that
the proposed tolerances for sorghum forage at 25 ppm and stover at 40
ppm are appropriate.  However, an amended Section F is required to
revise the proposed tolerance for sorghum grain from 9 ppm to 11 ppm.

The field trial data for the aspirated grain fractions of sorghum from
bulk samples treated at 1x for foliar treatments showed that residues
concentrated 49.4x.  Based on a processing factor of 49.4x and the HAFT
residue for sorghum grain of 8.46 ppm, the expected residues in the
aspirated grain fractions of sorghum is 420 ppm.  The previous tolerance
for aspirated grain fractions at 30 ppm was based on aspirated grain
fraction data from soybean seed.  Since it is Agency policy to establish
a tolerance for aspirated grain fraction based on the RAC with the
highest residues in the dust, the appropriate tolerance for aspirated
grain fractions is 420 ppm.  A revised Section F is required at 420 ppm
for aspirated grain fractions.  

The submitted residue data for wheat forage are adequate.  An amended
Section F is required to revise the proposed tolerance for wheat forage
to 25 ppm.  The wheat forage data may be translated to support the
requested tolerance for barley forage since the use patterns of wheat
and barley are identical.  A revised Section F to specify a tolerance
level of 25 ppm for barley forage is required.

The submitted residue data for cotton commodities are adequate to
support an amended use pattern reflecting in-furrow treatment at
planting followed by multiple postemergence foliar treatments;
currently, only the in-furrow use pattern is registered.  An amended
Section F is required to revise the proposed tolerances for undelinted
cottonseed at 0.6 ppm and for cotton gin byproducts at 45 ppm.

The petitioner requested to register use of azoxystrobin on wild rice,
based on translation of residue data from rice.  Although previous
requests to translate data were denied, HED now recommends that rice
grain data can be used to translate to wild rice based on similarities
in cultural practices.  The rice grain data may be translated to support
the requested tolerance for wild rice since the use patterns of rice and
wild rice are identical.  ARIA recommends for the proposed tolerance of
5.0 ppm on wild rice, grain.

The submitted cotton processing study is acceptable.  The results
indicate that the combined residues of azoxystrobin and its Z-isomer did
not concentrate in cotton meal, hulls, or refined oil processed from
undelinted cottonseed treated at up to 5x the maximum proposed seasonal
rate.

A sorghum processing study is not required for this action.  Table 1 of
OPPTS 860.1000 indicates that residue data are not needed at this time
for sorghum flour since it is used exclusively in the United States as a
component for drywall, and not as either a human food or a feedstuff. 
Acceptable wheat processing studies have also been submitted with
previous azoxystrobin petitions. 

There are adequate field rotational crop data to support the following
rotational crop restrictions on the product labels:  “Do not plant the
following crops for a period of 12 months (unless an azoxystrobin
product is registered for use on that crop):  buckwheat, millet, oats,
and rye.  A plantback interval of 36 days is required for leafy
vegetables (except Brassica) group; Brassica, leafy greens subgroup;
vegetables, root subgroup; vegetable (tuberous and corm subgroup; and
vegetables, leaves of root and tuber group.  Crops with registered
azoxystrobin uses may be planted immediately after the last
treatment.”  As tolerances on the commodities of primary crops
(barley, nongrass animal feeds (alfalfa and clover), sorghum, triticale,
and wheat) are being proposed, the rotational crop restrictions for
these crops are no longer required and have been removed from the
product labels.

No Codex MRLs have been established for azoxystrobin.  Canadian MRLs
have been established for residues of azoxystrobin, expressed in terms
of parent and the Z-isomer, in livestock commodities; no MRLs have been
established for the requested crops.  Mexican MRLS have also been
established for residues of ‘azoxistrobin’; however, no MRLs have
been established for the requested crops.

  SEQ CHAPTER \h \r 1 Regulatory Recommendations and Residue Chemistry
Deficiencies

Pending the submission of a revised Section F (see requirements under
860.1550 Proposed Tolerances), there are no residue chemistry issues
that would preclude granting a conditional registration for the crops
requested in PP#6F7106 and PP#7F7198.  The proposed uses and the
submitted and/or translated data support the following tolerances for
residues of azoxystrobin and the Z-isomer of azoxystrobin in/on the
following raw agricultural commodities:

Grain, aspirated fractions	420 ppm

Barley, forage	25 ppm

Animal feed, nongrass, forage, group 18	45 ppm

Animal feed, nongrass, hay, group 18	120 ppm

Sorghum, forage	25 ppm

Sorghum, grain	11 ppm

Sorghum, stover	40 ppm

Wheat, forage	25 ppm

Cotton, undelinted seed	0.6 ppm

Cotton, gin byproducts	45 ppm

Rice, wild, grain	5.0 ppm

860.1480 Meat, Milk, Poultry, and Eggs

	A revised Section F is required removing the requested tolerance
increases in milk and the fat, meat, and meat byproducts of cattle,
goat, horse, sheep, and swine.

	A revised Section F is required removing the requested tolerance
increases in eggs and the fat, meat, and meat byproducts of poultry.

860.1500 Crop Field Trials

	Barley:  A revised Section F to specify a tolerance level of 25 ppm for
barley forage is required.

	

Nongrass Animal Feed:  A revised Section F is required at 45 ppm for
forage and 120 ppm for hay of the nongrass animal feeds crop group 18.

	Sorghum:  An amended Section F is required to revise the proposed
tolerance for sorghum grain from 9 ppm to 11 ppm.  A revised Section F
is required at 420 ppm for aspirated grain fractions.  

	Wheat:  An amended Section F is required to revise the proposed
tolerance for wheat forage to 25 ppm.  

	Cotton:  An amended Section F is required to revise the proposed
tolerances for undelinted cottonseed at 0.6 ppm and for cotton gin
byproducts at 45 ppm.

A human health risk assessment is forthcoming in a separate document.

Background

The chemical structure and nomenclature of azoxystrobin and its
Z-isomer, and the physicochemical properties of the technical grade of
azoxystrobin are presented in Tables 1 and 2, respectively.

 

Common name	Azoxystrobin

Company experimental name	ICIA5504 (Zeneca), R215504 (Syngenta)

IUPAC name	methyl
(E)-2-{2-[6-(2-cyanophenoxy)pyramidin-4-yloxy]phenyl}-3-methoxyacrylate

CAS name
methyl-(E)-2-[[6-(2-cyanophenoxy)-4-pyrimidinyl]oxy]-(methoxymethylene)-
benzeneacetate

CAS registry number	131860-33-8

End-use products (EP)	Abound® Flowable Fungicide (EPA Reg. No.
100-1098)

 

Common name	Azoxystrobin, Z-isomer

Chemical name	methyl
(Z)-2-{2-[6-(2-cyanophenoxy)pyramidin-4-yloxy]phenyl}-3-methoxyacrylate

Table 2.   Physicochemical Properties of Technical Grade Azoxystrobin.

Parameter	Value	Reference

Melting point/range	114-116ºC	DP#s 218318 and 218448, 3/19/96, J.
Garbus

pH	6.4

	Density	1.25 g/cm3

	Water solubility	(20°C)

pH 5.2		6.7 mg/L

pH 7.0		6.7 mg/L

pH 9.2		5.9 mg/L

	Solvent solubility	(mg/mL at 20°C)

Hexane		0.057

Octanol		1.4

Methanol		20

Toluene		55

Acetone		86

Ethyl Acetate	130

Acetonitrile	340

Dichloromethane	400

	Vapor pressure	(20°C) 1.1x10-13 kPa (8.2x10-13 mmHg)

	Dissociation constant, pKa	Not dissociable

	Octanol/water partition coefficient, Log(KOW)	log POW = 2.5

	UV/visible absorption spectrum	Not available

	

860.1200  Directions for Use

A summary of the azoxystrobin end-use products proposed for use on the
crops discussed in this document is listed in Table 3.  Table 4 presents
the summary of proposed crop use patterns.  

Table 3.   Summary of Proposed Azoxystrobin End-Use Products.

Trade Name	Reg. No.	% ai of formulation	Formulation 

Type	Target Crops	Label Date

Abound® Flowable Fungicide 1	100-1098	22.9% ai 

(2.08 lb/gal) 	Flowable

Concentrate	Barley;  nongrass animal feeds forage, fodder, straw, and
hay group;  clover (and stands containing clover);  rice and wild rice;
sorghum; wheat and triticale	Undated supplemental label included in
Section B

Heritage® Fungicide 2	100-1093	50% ai 

(0.5 lb/gal)	Water dispersible

Granular	Cotton and wild rice	Undated supplemental label included in
Section B

1   The label in Section B of PP#7F7198 was for Quadris® Flowable
Fungicide, which has the same EPA Reg. No. as the Abound® Flowable
Fungicide.

2   The petition transmittal letters stated that the Heritage®
Fungicide will be amended to include new or amended uses on barley,
clover, cotton, nongrass animal feeds, sorghum, wheat, and wild rice. 
The petitioner stated that they will submit an amended label for
Heritage® (EPA Reg. No. 100-1093) in the future as a ‘me-too use’.

Table 4.   Summary of Directions for Use of Azoxystrobin.

Applic. Timing, Type, and Equip. 	Formulation

[EPA Reg. No.]	Applic. Rate 

(lb ai/A)	Max. No. Applic. per Season	Max. Seasonal Applic. Rate

(lb ai/A)	PHI

(days)	Use Directions and Limitations

Barley

Foliar

Ground, aerial or chemigation	2.08 lb/gal FlC

[100-1098]	0.10-0.20	2	0.40	14 (forage & hay)

45 (grain & straw)	Begin applications prior to disease development and
up to when barley is at the late head emergence (Feekes 10.5 or
Zadok’s 59) stage.  A crop oil concentrate adjuvant may be added at
1.0% v/v.  

Clover (and stands containing Clover)

Foliar

Ground, aerial or chemigation	2.08 lb/gal FlC

[100-1098]	0.10-0.25	Not specified	0.75 for pure stands of clover or
mixed with grasses	14 (forage & hay)	Begin applications prior to disease
development and throughout the season with 7-14 day retreatment
intervals.  Use of an adjuvant such as crop oil concentrate or non-ionic
surfactant is recommended.

Cotton

Foliar

Ground, aerial	2.08 lb/gal FlC

[100-1098]	0.1-0.15	3	0.45	45	Begin applications prior to or in the
early stages of disease development and when cotton is at the pinhead to
first bloom stage; subsequent applications are to be made on a 14-21 day
schedule.  Minimum volumes for air and ground applications are 5 and 10
gal/A, respectively.  An adjuvant may be added at recommended rates.

In-furrow at planting	2.08 lb/gal FlC

[100-1098]	0.10-0.20 oz ai/1,000 row ft 1 	NA	0.20 oz ai/

1000 row ft	NA	Apply in 3-7 gallons of water at planting, directed into
the furrow just before seed is covered.

Nongrass Animal Feeds Forage, Fodder, Straw and Hay 

[Stands including:  Alfalfa, Bean, velvet, Kudzu, Lespedeza, Lupin,
Sainfoin, Trefoil, Vetch, Vetch crown, Vetch milk, and Clover (see
clover specific instructions)] 

Foliar

Ground, aerial or chemigation	2.08 lb/gal FlC

[100-1098]	0.10-0.25	Not specified	0.75	14 (forage & hay)	Not for use on
rangeland; for pure stands of grasses see uses established for grasses
(grown for seed).  Begin applications prior to disease development.  Use
of an adjuvant such as crop oil concentrate or non-ionic surfactant is
recommended.

Rice and Wild Rice

Foliar

Ground, aerial or chemigation	2.08 lb/gal FlC

[100-1098]	0.10-0.30	2	0.70	28	Do not treat rice fields used for
aquaculture of fish or crustaceans; and do not release irrigation or
flood water for at least 14 days after last application.  For foliar and
panicle diseases, apply prior to disease development and for panicle
blast, when rice is at the mid-boot to boot-split stage but prior to
full head emergence; a second application may be made when panicles are
~60-90% emerged from the boot (7-14 days later).  For other stem/sheath
diseases apply when disease is <4 inches above water line usually
between panicle differentiation (PD) 6 days PD +10 days PD (wild rice:
apply during tillering, boot, early heading or at initial sign of
disease).  Minimum volume for air applications is 5 gal/A.  An adjuvant
may be added at recommended rates.

Sorghum

Foliar

Ground, aerial or chemigation	2.08 lb/gal FlC

[100-1098]	0.10-0.25	Not specified	0.5 (forage)

0.75 (grain & stover)	14	Begin applications prior to disease
development.  An adjuvant may be added at recommended rates.

In-furrow

0.1-0.2  oz ai/1,000 row ft	NA	Not specified	NA	For soilborne/seedling
disease control; apply in 3-15 gal/A water directed into the furrow
before seed is covered (master label).

Wheat and Triticale

Foliar

Ground, aerial or chemigation	2.08 lb/gal FlC

[100-1098]	0.07-0.20	Not specified	0.40	14 (forage & hay)

45 (grain & straw)	Begin applications prior to disease development and
up to when wheat is at the late head emergence (Feekes 10.5 or Zadok’s
59) stage.  A crop oil concentrate adjuvant may be added at 1.0% v/v.  

1  According to the most recent label for Abound® Flowable Fungicide
approved 6/30/06, the in-furrow rate of 0.10-0.20 oz ai/1,000 row ft is
equivalent to 0.08-0.30 lb ai/A based on 22-40 inch row spacing.

For all crops listed in Table 4, the use directions for Abound®
Flowable Fungicide specify that it should be integrated into an overall
disease and pest management strategy and that for resistance management,
no more than two foliar applications of Abound® Flowable Fungicide or
other Group 11 fungicides should be made before alternating with a
fungicide having a different mode of action (not in Group 11).  For
rice, resistance management further specifies that when Abound®
Flowable Fungicide is applied for panicle blast on continuous rice
acreage (no rotation to other crops), no more than 2 sequential foliar
applications of Abound® Flowable Fungicide or other Group 11 fungicides
be made over multiple years before alternating with a different acting
fungicide.

The label for the Abound® Flowable Fungicide specifies the following
rotational crop restrictions: “Do not plant the following crops for a
period of 12 months (unless an azoxystrobin product is registered for
use on that crop): buckwheat, millet, oats and rye.  A plantback
interval of 36 days is required for leafy vegetables (except Brassica)
group; Brassica, leafy greens subgroup; vegetables, root subgroup;
vegetable (tuberous and corm subgroup; and vegetables, leaves of root
and tuber group.  Crops with registered azoxystrobin may be planted
immediately after the last treatment.”  It is noted that the above
rotational crop restrictions is a revision of the rotational crop
restrictions on the currently registered label dated 2/23/2007, to
remove the 12-month plantback interval restriction for barley, nongrass
animal feeds (alfalfa and clover), sorghum, triticale, wheat, and wild
rice. 

Conclusions:  The label directions are adequate to allow evaluation of
the residue data relative to the proposed use.

860.1300 Nature of the Residue - Plants

PP#5F4541, DP#s 218318 and 218448, 3/19/96, J. Garbus 

PP#6F4762, DP#s 230634, 230635, 230636 and 230637, 4/25/97, L. Kutney 

HED Metabolism Assessment Review Committee Decision Memo, DP# 251683,
2/30/98, W. Wassell

Adequate metabolism studies on grapes, peanuts, and wheat were submitted
in conjunction with earlier azoxystrobin petitions, PP#s 5F4541 and
6F4762.  Azoxystrobin undergoes photochemical isomerization to produce
the Z-isomer and is extensively metabolized in plants.  The parent
compound undergoes cleavage of the ether linkages between the
phenylacrylate and pyrimidinyl rings and the cyanophenyl and pyrimidinyl
rings, with subsequent oxidation, hydrolysis, and/or reduction of the
primary metabolites to form numerous secondary metabolites. 
Azoxystrobin is systemic.  HED has determined that the residues of
concern in/on plants for the tolerance expression and risk assessment
purposes are azoxystrobin and its Z-isomer.

860.1300 Nature of the Residue - Livestock

PP#5F4541, DP#s 218318 and 218448, 3/19/96, J. Garbus 

PP#6F4762, DP#s 230634, 230635, 230636 and 230637, 4/25/97, L. Kutney 

HED Metabolism Assessment Review Committee Decision Memo, DP# 251683,
2/30/98, W. Wassell

The nature of the residue in animals is adequately understood based on
acceptable metabolism studies conducted on goats and laying hens.  HED
has determined that the residue of concern in livestock is parent
azoxystrobin only. 

860.1340 Residue Analytical Methods

Enforcement methods

PP#s 5F4541 & 6F4762, DP# 235342, 5/30/97, C. Stafford

PP# 7F4864, DP#s 249657 and 249668, 1/25/99, D. Dotson 

Plants:  For analysis of plant commodities for residues of azoxystrobin
and its Z-isomer, a GC/NPD method (RAM 243/04) has undergone method
validation by ACB/BEAD.  BEAD comments have been incorporated, and the
revised method (designated RAM 243, dated 5/15/98) has been submitted to
FDA for inclusion in PAM, Volume II.  The method limit of quantitation
(LOQ) is 0.01 ppm for each analyte in various crop matrices.  

Livestock:  For analysis of animal commodities for residues of
azoxystrobin per se, a GC/NPD method (RAM 255/01) has been validated by
an independent laboratory for the analysis of milk, liver and eggs, and
by the EPA analytical laboratory for the analysis of milk and liver. 
The EPA laboratory written report (with an EPA addendum to accompany the
method) and the method will be submitted to FDA for inclusion in PAM,
Volume II.  In the interim, copies are available from PIRIB/IRSD (7502P)
and ACB/BEAD (7503P).  The method LOQ is 0.0025 ppm and 0.01 ppm for
each analyte in milk and tissues, respectively.

Data-collection method

DER Reference:  47096401.der.doc (plants)

An LC/MS/MS method, RAM 305/03, was submitted for the determination of
residues of azoxystrobin and its Z-isomer (R230310) in/on crop
commodities.  RAM 305/03 was the data-collection method used for the
analysis of samples from the crop field trial and processing studies
associated with the current petitions.  Briefly, residues of
azoxystrobin and R230310 were extracted from crop matrices with
acetonitrile (ACN):water (90:10, v:v) and centrifuged.  The supernatant
was diluted with ACN:water (30:70, v:v), loaded onto a C18 solid-phase
extraction (SPE) column, and residues were eluted with ethyl
acetate:dichloromethane (55:45, v:v).  The eluate was evaporated,
dissolved in ACN:water (50:50, v:v), and filtered if necessary for
LC/MS/MS analysis.  The LC/MS/MS method uses a single ion transition,
m/z 404.2→372.4, to quantitate azoxystrobin and R230310 residues in/on
plant commodities.  For confirmation, the LC/MS/MS method may be used to
monitor an additional ion transition, m/z 404.2→343.8.

The method was adequately validated using fortified samples of beer,
mandarin, cabbage, wheat grain, wheat straw, wheat flour, and sunflower
seed.  Overall, recoveries of azoxystrobin ranged 61-118% (average 94%
± 7.8% standard deviation), and recoveries of R230310 ranged 58-108%
(91 ± 6.6%) from samples fortified at 0.01 ppm and at 0.10 ppm for beer
and wheat flour, 10.0 ppm for mandarin, 0.03 ppm for cabbage and wheat
grain, 7.5 ppm for wheat straw, or 0.05 ppm for sunflower seed.  The
validated limit of quantitation (LOQ) was 0.01 ppm and the limit of
detection (LOD) was estimated at 0.005 ppm for each analyte in each
matrix. 

Concurrent method recovery data were included with the crop field trial
studies and the processing study; however, the fortification levels and
samples used in method validation are not adequate to bracket expected
residue levels.  Adequate concurrent recovery data were submitted for
alfalfa and clover forage (0.01-2 ppm); alfalfa and clover hay (0.01-20
ppm); cottonseed (0.01-2 ppm) and gin byproducts (0.01-15 ppm); sorghum
forage (0.01-10 ppm), stover (0.01-10 ppm), grain (0.01-20 ppm), and
aspirated grain fractions (0.01-2 ppm); and wheat forage (0.01-20 ppm). 
Fortification levels in the concurrent recovery studies were not
adequate to bracket expected residue levels for azoxystrobin in
aspirated grain fractions (106 ppm), cotton gin byproducts (31 ppm),
nongrass animal feeds, hay (52 ppm), or sorghum stover (15 ppm);
however, wheat forage validation data will support the expected levels
of residues in nongrass animal feeds, forage.  

Conclusions:   There are adequate residue analytical methods for
tolerance enforcement.  For analysis of plant commodities for residues
of azoxystrobin and its Z-isomer, a GC/NPD method (RAM 243/04) has
undergone method validation by ACB/BEAD.  For analysis of animal
commodities for residues of azoxystrobin per se, a GC/NPD method (RAM
255/01) has been validated by an independent laboratory for the analysis
of milk, liver and eggs, and by the EPA analytical laboratory for the
analysis of milk and liver.  The EPA laboratory written report (with an
EPA addendum to accompany the method) and the method were submitted to
FDA for inclusion in PAM, Volume II.

For analysis of samples from the crop field trial and processing studies
associated with the current petitions, LC/MS/MS method, RAM 305/03 was
used as the data-collection method.  RAM 305/03 was adequately validated
at fortification levels of 0.01-7.5 ppm.  Although the fortification
levels in the concurrent recovery studies were not adequate to bracket
expected residue levels for azoxystrobin in aspirated grain fractions
(106 ppm), cotton gin byproducts (31 ppm), nongrass animal feeds, hay
(52 ppm), or sorghum stover (15 ppm), the submitted concurrent
recoveries were adequate and there is an adequate tolerance enforcement
method; therefore, no further data are required.  The data gathering
method is adequate to support the tolerance requests. 

860.1360 Multiresidue Methods

PP#5F4541, Residue Chemistry Memo, DP#s 218318 and 218448, 3/19/96, J.
Garbus 

Data have previously been submitted pertaining to the multiresidue
methods testing of azoxystrobin in conjunction with the grape petition
(PP#5F4541).  The data indicate that azoxystrobin could not be recovered
through application of the multiresidue protocols.  These data have been
forwarded to FDA for inclusion in PAM I.

860.1380 Storage Stability

PP# 7F4864, DP#s 248887 and 249671, 10/14/98, D. Dotson, et al 

PP# 7F4864, DP#s 249657 and 249668, 1/25/99, D. Dotson 

PP# 9F6058, DP#s 283588 and 287062, ID#s 100-1098 & 100-1093, 2/6/03, N.
Dodd

Adequate storage stability data are available indicating that
azoxystrobin and its Z-isomer are reasonably stable under frozen
conditions in/on fortified samples of diverse crops.  In previous
studies, residues were determined to be stable in/on apples, bananas,
carrot, cucumbers, grapes, leaf lettuce, oil seed rape, peaches, winter
wheat straw, wheat forage, and wine for 2 years.  Over the two-year
period, residues of both azoxystrobin and its Z-isomer decreased by up
to 20% in winter wheat grain and by up to 27% (azoxystrobin only) in
tomato, peanut, and pecan, but all recoveries were >70%; residues in
these crops were stable (without decrease) for up to 6-8 months.

Previous studies conducted on processed commodities demonstrated that
fortified residues of azoxystrobin and its Z-isomer were generally
stable under frozen conditions in peanut oil and meal, tomato juice and
paste, and wheat bran for up to one year, and in soybean meal, corn
grits, and orange oil, juice and pulp for at least 2 years.

The storage intervals and durations for samples collected from the
magnitude of the residue and processing studies submitted with these
petitions are presented below in Table 5.

Table 5.   Summary of Storage Conditions and Durations of Samples from
Crop Field Trials.  

Matrix 	MRID	Storage

Temperature (°C)	Actual Storage

Duration (Months)	Interval of Demonstrated Storage Stability 

Alfalfa, forage	46924301	~-20	9.3-17.0	2 years in/on diverse crops
including wheat forage and straw

Alfalfa, hay

	9.3-17.2

	Clover, forage

	6.3-17.3

	Clover, hay

	9.3-17.3

	Cotton, undelinted seed	47096402	~-20	6.3-10.0	2 years in/on diverse
crops including oil seed rape and wheat matrices (20% decline in grain)

Cotton, gin byproducts

	6.3-11.1

	Cotton, undelinted seed

(for processing)	47096402	~-20	8.6-9.7	2 years in/on diverse crops
including oil seed rape

Cotton processed hulls, 

meal and refined oil

<-10	2.3-4.4	1 year in/on diverse processed commodities including peanut
and soybean meal, and peanut and orange oil

Sorghum, forage	46924302	~-20	3.2-17.7	2 years in/on diverse crops
including wheat forage and straw

Sorghum, stover

	12.5-16.7

	Sorghum, grain

	3.5-16.7	2 years in/on diverse crops including wheat grain (20%
decline)

Wheat, forage	46924303	<-20	0.1-12.2	2 years in wheat forage

Conclusions:  There are adequate storage stability data from previous
submissions to validate sample storage conditions and durations in the
current petitions.  Residues of azoxystrobin and its Z-isomer were found
to be relatively stable over a wide range of commodities under frozen
storage conditions for 1-2 years.

860.1400 Water, Fish, and Irrigated Crops

No studies concerning this guideline topic have been submitted because
the established/proposed uses on rice include a restriction that rice
fields used for aquaculture of fish or crustaceans may not be treated,
and irrigation or flood water may not be released for at least 14 days
after last application.

860.1460 Food Handling

This guideline requirement is not relevant to the current petitions as
there are no food-handling uses being proposed for azoxystrobin.

860.1480 Meat, Milk, Poultry, and Eggs

Tolerances for residues of azoxystrobin per se are currently established
[40 CFR §180.507(a)(2)] for the fat (0.03 ppm), meat (0.01 ppm), and
meat byproducts (0.07 ppm) of cattle, goat, horse, and sheep.  A
tolerance of 0.01 ppm each has been established for hog fat, meat, and
meat byproducts.  A milk tolerance of 0.006 ppm is also established.  No
tolerances for eggs and poultry meat and meat byproducts have been
established.

Livestock dietary burdens

PP# 9F6058, DP# 260134, 9/6/00, M. Nelson

The potential for secondary transfer of azoxystrobin residues in meat,
milk, poultry, and eggs exists because there are several livestock
feedstuffs which are relevant to this action.  These include barley
(grain, hay, and straw), cotton (seed, gin byproducts, meal, and hulls),
nongrass animal feeds (forage, hay, meal, and silage), rice (grain,
straw, hulls, and bran), sorghum (grain, forage, stover, and aspirated
grain fractions), and wheat (grain, forage, hay, straw, aspirated grain
fractions, and milled byproducts.  In addition, numerous livestock
feedstuffs are currently registered with established tolerances.  The
Agency previously calculated the maximum theoretical maximum dietary
burdens (MTDB) of azoxystrobin to livestock in conjunction with PP#
9F6058.  Using the worst-case scenario for the previously requested and
established tolerances, the calculated MTDBs were 105.8 ppm for beef
cattle, 73.7 ppm for dairy cattle, 9.5 ppm for swine, and 7.3 ppm for
poultry.

Using the most recent guidance concerning revisions of feedstuff
percentages in Table 1 (October 2006) and constructing reasonably
balanced livestock diets, the livestock dietary burdens of azoxystrobin
are presented in Table 6 (email, J. Stokes, 2/15/08).  The calculated
dietary burdens of azoxystrobin are 47.9 ppm for beef cattle, 58.7 ppm
for dairy cattle, and 9.0 ppm for poultry and swine.

Table 6.   Calculation of Dietary Burdens of Azoxystrobin Residues to
Livestock.

Feedstuff	Type1	% Dry Matter2	% Diet2	Recommended/

Established Tolerance (ppm)	Dietary Contribution (ppm)3

Beef Cattle

Nongrass animal feeds, hay 	R	89	10	120	13.5

Aspirated grain fractions	CC	85	5	420	24.7

Sorghum grain	CC	86	75	11	9.6

Canola meal	PC	88	10	1.0	0.13

TOTAL BURDEN	--	--	100	--	47.9

Dairy Cattle

Nongrass animal feeds, hay 	R	89	15	120	20.2

Nongrass animal feeds, forage	R	35	10	45	12.9

Corn, field, silage	R	40	10	12	 3.0

Turnip tops	R	30	10	50	16.7

Sorghum grain	CC	86	45	11	5.8

Canola meal	PC	88	10	1.0	0.13

TOTAL BURDEN	--	--	100	--	58.7

Poultry

Sorghum grain	CC	86	80	11	8.8

Canola meal	PC	88	15	1.0	0.15

Cottonseed meal 	      PC	89	5	0.6	0.03

TOTAL BURDEN	--	--	100	--	9.0

Swine

Sorghum grain	CC	86	80	11	8.8

Canola meal	PC	88	15	1.0	0.15

Soybean meal 	      PC	92	5	0.5	0.03

TOTAL BURDEN	--	--	100	--	9.0

1  R:  Roughage; CC:  Carbohydrate concentrate; PC:  Protein
concentrate.

2  OPPTS 860.1000 Table 1 Feedstuffs (October 2006).  

3  Contribution = ([tolerance /% DM] X % diet) for beef and dairy
cattle; contribution = ([tolerance] X % diet) for poultry and swine. 

Comments:  

1)  Removed nongrass forage from beef—not available to finishing
feedlot beef

2)  Turnip tops removed from beef--- not available to finishing feedlot
beef

3)  Turnip tops in dairy—used in PA, VA, and TN as forage/green chop
for dairy  

4)  Added corn silage to dairy—Cannot feed more that 25% nongrass
commodities as bloats dairy cows.

5)  Soybean hay removed—very small amount produced and fed to local
growing  beef and nonlactating cows—not high quality forage for high
production milk cows

6)   Other feedstuffs listed in 180.507 maybe more readily available to
finishing beef and mature dairy cows, but the nongrass entries will
always be the drivers.  Alfalfa is readily fed to beef and dairy across
the US.   

Ruminants and Swine

Conclusions:  The existing azoxystrobin tolerances for milk and the fat,
meat, and meat byproducts of ruminants and swine were established using
MTDB that are higher than the current dietary burdens; therefore, no
increases in associated livestock items of regulatory interest are
required.  A revised Section F is required removing the requested
tolerance increases in milk and the fat, meat, and meat byproducts of
cattle, goat, horse, sheep, and swine. 

Poultry Feeding Study

Residue Chemistry Memo, DP#s 249657 and 249668, 1/25/99, D. Dotson
(PP#7F4864)

A poultry feeding study with azoxystrobin was previously submitted and
reviewed in conjunction with PP#7F4864.  In the referenced poultry
feeding study, the dosing level was 60 ppm (6.67x the recalculated
dietary burden of 8.98 ppm for poultry; see Table 6).  Since no residues
of the Z-isomer were identified in the poultry metabolism study, egg and
tissue samples from the feeding study were analyzed for azoxystrobin
residues only.  The LOQ of the method (RAM 255) was 0.01 ppm.  No
quantifiable residues of azoxystrobin were reported in any egg or
poultry tissue sample.  

Conclusions:  The proposed and amended uses of azoxystrobin on the
poultry feed items addressed in this document are not expected to alter
the Agency’s previous conclusion that there is no reasonable
expectation of finite residues in poultry commodities [Category 3 of
§180.6(a)].  No tolerances are needed for poultry and eggs.  The Agency
will periodically assess this determination if additional poultry feed
items are proposed in the future.  A revised Section F is required
removing the requested tolerance increases in eggs and the fat, meat,
and meat byproducts of poultry.

860.1500 Crop Field Trials

The field trial data submitted in support of the proposed/amended uses
were generated using a flowable concentrate formulation of azoxystrobin.
 Adequate bridging data (PP#9F06058, DP#283588 and 287062, 2/6/03, N.
Dodd) are available to support the use of WDG and FlC formulations on
the crops discussed herein.  Based on bridging studies from the 80 WG
formulation (also called 80 WDG, a water dispersible granular) to the SC
formulation (also called FlC, a flowable concentrate) in celery, green
onion, orange, garden beet, spinach, peaches, and tomatoes the ChemSAC
(in a meeting on 12/18/02) concluded that statistical differences in
resulting residues between the WG and SC formulations may be considered
equivalent in terms of the expected residue levels.  Hence, no further
side-by-side azoxystrobin trials are needed for these two formulations.

Barley

PP#9F6058, DP# 260134, 9/26/00, M. Nelson 

Azoxystrobin tolerances for barley grain (0.1 ppm), hay (15.0 ppm), and
straw (4.0 ppm) have been established based on residue data translated
from corresponding wheat commodities (PP#9F6058).  No residue data for
barley forage were submitted to support the requested tolerance of 30
ppm for this commodity.  

Conclusions:	Since the use patterns of wheat and barley remain
identical, the submitted data for wheat forage may be used in support of
a tolerance on barley forage.  However, the proposed tolerance level is
not appropriate.  A revised Section F to specify a tolerance level of 25
ppm for barley forage is required.

Nongrass Animal Feeds (Forage, Fodder, Straw, and Hay) (Crop Group 18)

PP#4E6823, DP# 328894, 6/19/06, W. Cutchin

46924301.der.doc (alfalfa and clover)

Syngenta Crop Protection, Inc. has submitted field trial data for
azoxystrobin on clover and alfalfa, the representative crops of nongrass
animal feeds, crop group 18.  Seventeen field trials were conducted in
the United States between the 2004-2005 growing seasons.  Eight clover
trials were conducted in Zones 1 (NY; 1 trial), 2 (NC; 1 trial), 5 (IL,
WI; 2 trials), 6 (TX; 1 trial), 7 (NE; 1 trial), 8 (TX; 1 trial), and 10
(CA; 1 trial).  Nine alfalfa trials were conducted in Zones 1 (NY; 1
trial), 5 (IL, MN, SD, WI; 4 trials), 7 (SD; 1 trial), 9 (CO; 1 trial),
10 (CA; 1 trial), and 11 (ID; 1 trial).  

Each trial consisted of one untreated plot and one treated plot.  Stands
of clover or alfalfa received three foliar broadcast applications of a
2.08 lb/gal FlC formulation of azoxystrobin at 0.24-0.26 lb
ai/A/application, for a total rate of 0.73-0.76 lb ai/A (1x the maximum
proposed seasonal rate of 0.75 lb ai/A).  Applications were made to
clover with 12- to 16-day RTIs, while applications to alfalfa were made
without a set RTI.  Alfalfa was harvested after each application and
allowed to re-grow prior to the next application.  The retreatment
intervals for alfalfa ranged from 25-83 days.  All applications were
made using ground equipment in spray volumes of 2-20 gal/A with an
adjuvant added to the spray solutions.

Samples of clover forage and hay were harvested 13-15 DALA.  Samples of
alfalfa forage and hay were harvested 13-14 DAT, representing the first,
second and third cuttings.  Additional samples of clover and alfalfa
forage and hay were collected from two trials each at 0, 3, 7, and 21
days after first treatment (alfalfa) or days after last treatment
(clover) to generate residue decline data. 

Samples of clover and alfalfa forage and hay were analyzed for residues
of azoxystrobin and its Z-isomer (R230310) using LC/MS/MS Method RAM
305/03.  The validated LOQ was 0.01 ppm for each analyte in all
matrices, and the reported LOD was 0.005 ppm.  The method was adequate
for data collection based on acceptable concurrent method recoveries;
however, it is noted that the concurrent method validation fortification
levels did not encompass the maximum residues of azoxystrobin observed
in treated samples of forage (15 ppm) or hay (52 ppm).

Samples were stored frozen (<-20 °C) prior to analysis for up to 17.3
months for clover and 17.2 months for alfalfa matrices.  Adequate
storage stability data are available to support the storage conditions
and durations of samples from the clover and alfalfa field trials.

A summary of residue data from the alfalfa and clover field trials is
presented in Table 7.  Maximum residues of azoxystrobin and its Z-isomer
(R230310), respectively, were 15.0 and 1.30 ppm in/on clover forage, and
52.0 and 3.5 ppm in/on clover hay harvested 13-15 days following three
foliar applications for a total rate of 0.73-0.77 lb ai/A; maximum
combined residues (azoxystrobin + R230310) were 16.0 ppm in/on clover
forage and 55.5 ppm in/on clover hay. 

For first-cutting alfalfa, maximum residues of azoxystrobin and R230310,
respectively, were 4.40 and 0.26 ppm in/on forage, and 15.0 and 0.86 ppm
in/on hay, harvested 14 days following a single foliar application for a
total rate of 0.25-0.26 lb ai/A; maximum combined residues (azoxystrobin
+ R230310) were 4.66 ppm in/on alfalfa forage and 15.86 ppm in/on
alfalfa hay.  

For second-cutting alfalfa, maximum residues of azoxystrobin and
R230310, respectively, were 8.30 and 0.43 ppm in/on forage, and 44.0 and
1.80 ppm in/on hay, harvested 13-14 days following two foliar
applications for a total rate of 0.50-0.51 lb ai/A; maximum combined
residues (azoxystrobin + R230310) were 8.54 ppm in/on alfalfa forage and
45.3 ppm in/on alfalfa hay.  

For third-cutting alfalfa, maximum residues of azoxystrobin and R230310,
respectively, were 8.50 and 0.51 ppm in/on forage, and 30.0 and 0.89 ppm
in/on hay, harvested 13-14 days following three foliar applications for
a total rate of 0.75-0.76 lb ai/A; maximum combined residues
(azoxystrobin + R230310) were 8.75 ppm in/on alfalfa forage and 30.74
ppm in/on alfalfa hay.

Table 7.   Summary of Residue Data from Alfalfa and Clover Field Trials
with Azoxystrobin.

Commodity	Total Applic. Rate

 (lb ai/A)	PHI (days)	Combined Residue Levels of Azoxystrobin and its
Z-Isomer (ppm)

	n	Min.	Max.	HAFT	Median

(STMdR)	Mean

(STMR)	Std. Dev.

Proposed Use Pattern:  Maximum seasonal rate of 0.75 lb ai/A with a
14-day PHI

Clover Forage	0.73-0.77	13-15	16	0.64	16.0	13.87	4.45	6.01	4.95

Clover Hay	0.73-0.77	13-15	16	3.37	55.5	47.60	16.29	18.42	14.83

Alfalfa Forage	0.25-0.26	14	18	<0.10	4.66	4.44	0.58	1.05	1.32

	0.50-0.51	13-14	18	<0.10	8.54	6.95	0.82	2.28	2.64

	0.75-0.76	13-14	18	<0.12	8.75	8.48	1.91	3.33	3.07

Alfalfa Hay	0.25-0.26	14	18	0.35	15.86	15.77	1.87	3.19	4.69

	0.50-0.51	13-14	18	0.46	45.30	43.85	2.32	9.61	14.5

	0.75-0.76	13-14	18	0.27	30.74	26.17	6.60	8.63	8.07

The residue decline data indicated that residues of azoxystrobin and
R230310 generally declined in/on alfalfa and clover forage and hay with
later sampling intervals.

Conclusions:  Geographic representation of residue data submitted for
nongrass animal feeds, crop group 18, is not in full compliance with the
guideline.  According to Table 2 of OPPTS 860.1500, a total of 18 field
trials is required to establish a tolerance for crop group 18; only 17
field trials were conducted.  However, no additional field trial data
will be required since ARIA has previously determined in PP#4E6823 (DP#
328894, 6/19/06, W. Cutchin) that a reduced number of trials may be
conducted to establish tolerances for this crop group.

The field trial data for alfalfa and clover forage and hay were entered
into the Agency’s tolerance spreadsheet as specified by the Guidance
for Setting Pesticide Tolerances Based on Field Trial Data SOP to
determine appropriate tolerance levels; see Appendix I.  The tolerance
spreadsheet indicates that the proposed tolerances are inadequate.  A
revised Section F is required at 45 ppm for forage and 120 ppm for hay
of the nongrass animal feeds crop group 18. 

Sorghum

PP#7F4864, DP# 249657, 1/25/99, D. Dotson

PP#9F6058, DP# 260134, 9/26/00, M. Nelson

46924302.der.doc (grain sorghum)

Syngenta Crop Protection, Inc. has submitted field trial data for
azoxystrobin on sorghum.  Twelve sorghum field trials were conducted in
the United States in Zones 2 (SC; 1 trial), 4 (LA; 1 trial), 5 (KS, MO,
NE, SD; 4 trials), 6 (OK, TX; 2 trials), 7 (NE; 1 trial), and 8 (CO, NM,
TX; 3 trials) during the 2004 growing season.

  

Each trial consisted of one untreated plot and two treated plots.  For
the harvest of forage, one plot of sorghum received two foliar broadcast
applications of a 2.08 lb/gal FlC formulation of azoxystrobin at
0.24-0.26 lb ai/A/application for a total of 0.49-0.51 lb ai/A.  For the
harvest of grain and stover, a second plot received three foliar
broadcast applications of the 2.08 lb/gal FlC at the same single
application rate for a total of 0.74-0.78 lb ai/A.  The total applied
rates are 1x the proposed maximum foliar seasonal rates for harvest of
forage and grain/stover.  Applications were made with 6- to 8-day
retreatment intervals using ground equipment in spray volumes of 3-20
gal/A with an adjuvant added to the spray solutions.

Sorghum forage was collected 14-15 days after the last of two
applications and sorghum stover and grain were collected 13-17 days
after the last of three applications.  Additional samples were collected
from two trial sites at 0, 3, 7 and 21 days after treatment to generate
residue decline data. 

Samples of sorghum forage, stover and grain were analyzed for residues
of azoxystrobin and its Z-isomer (R230310) using LC/MS/MS Method RAM
305/03.  The validated LOQ was 0.01 ppm for each analyte in all sorghum
matrices, and the reported LOD was 0.005 ppm.  The method was adequate
for data collection based on acceptable concurrent method recoveries;
however, it is noted that the concurrent method validation fortification
levels did not encompass the maximum residues of azoxystrobin observed
in/on treated samples of stover (15 ppm) or aspirated grain fractions
(106 ppm).

Sorghum samples were stored frozen (<-20°C) prior to analysis for up to
17.7 months for forage, and 16.7 months for stover and grain.  Adequate
storage stability data are available to support the storage conditions
and durations of the samples from the sorghum field trials.

A summary of residue data from the sorghum field trials is presented in
Table 8.  Maximum residues of azoxystrobin and R230310, respectively,
were 9.00 and 1.00 ppm in/on sorghum forage harvested 14-15 days
following two foliar applications for a total rate of 0.49-0.51 lb ai/A;
maximum combined residues (azoxystrobin + R230310) were 10.0 ppm in/on
forage.  

Maximum residues of azoxystrobin and R230310, respectively, were 15.00
and 2.00 ppm in/on sorghum stover, and 8.10 and 0.47 ppm in/on sorghum
grain harvested 13-17 days following three foliar applications for a
total rate of 0.74-0.78 lb ai/A; maximum combined residues (azoxystrobin
+ R230310) were 8.57 ppm in/on grain and 17.0 ppm in/on stover. 
Residues of azoxystrobin and R230310, respectively, were 106.0 ppm and
4.6 ppm in/on aspirated grain fractions (from a single trial sample);
combined residues (azoxystrobin + R230310) were 110.6 ppm.

Table 8.   Summary of Residue Data from Sorghum Field Trials with
Azoxystrobin.

Commodity	Total Applic. Rate

 (lb ai/A)	PHI (days)	Combined Residue Levels of Azoxystrobin and its
Z-Isomer (ppm)

	n	Min.	Max.	HAFT	Median

(STMdR)	Mean

(STMR)	Std. Dev.

Proposed Use Pattern:   In-furrow application at 0.1-0.2 oz ai/1,000 row
ft + multiple postemergence foliar sprays at maximums of 0.5 lb ai/A
(for forage) or 0.75 lb ai/A (for grain & stover).  The proposed PHI is
14 days.

Forage	0.49-0.51	14-15	24	0.16	10.0	8.00	1.56	2.36	2.60

Stover	0.74-0.78	13-17	24	0.38	17.0	16.45	3.35	4.86	4.83

Grain	0.74-0.78	13-17	24	0.38	8.57	8.46	2.04	2.65	2.08

Aspirated grain fractions 1	0.75	13	1	110.6 1	N/A	N/A	N/A	N/A

1  Processed from a bulk sorghum grain sample bearing combined residues
of 2.24 ppm.  The calculated processing factor is 49.4x.

The residue decline data indicated that residues of azoxystrobin and
R230310 generally declined in/on sorghum forage, stover and grain with
later sampling intervals.

Conclusions:   Although geographical representation is adequate, the
submitted residue data for sorghum are not adequate because they do not
fully reflect the proposed use patterns.  The residue data only reflect
the proposed use pattern for postemergence foliar applications and did
not reflect the in-furrow treatment.  Previously submitted data showed
non-detectable residues (<0.01 ppm for azoxystrobin and its Z isomer) on
undelinted cottonseed and cotton gin byproducts when cotton was treated
foliarly following an in-furrow application (PP#9F6058, DP# 260134,
9/26/00, M. Nelson).  It is likely that the bulk of residues will result
from foliar uses.

The field trial data for sorghum forage, grain, and stover were entered
into the Agency’s tolerance spreadsheet as specified by the Guidance
for Setting Pesticide Tolerances Based on Field Trial Data SOP to
determine appropriate temporary tolerance levels; see Appendix I.  The
tolerance spreadsheet recommends tolerances of 25 ppm for sorghum
forage, 11 ppm for sorghum grain, and 40 ppm for sorghum stover.  The
proposed tolerances for sorghum forage (25 ppm) and stover (40 ppm) are
identical with the tolerance spreadsheet recommended tolerances. 
However, an amended Section F is required to revise the proposed
tolerance for sorghum grain from 9 ppm to 11 ppm.

The field trial data for the aspirated grain fractions of sorghum from
bulk samples treated at 1x for foliar treatments showed that the
combined residues of azoxystrobin and its Z-isomer were 110.6 ppm; the
combined residues concentrated 49.4x.  Based on a processing factor of
49.4x and the HAFT residue for sorghum grain (8.46 ppm), the expected
residues in the aspirated grain fractions of sorghum is 417.9 ppm.  It
is noted that 40 CFR §180.507(a)(1) currently lists two tolerances for
aspirated grain fractions.  The 10 ppm tolerance was based on aspirated
grain fraction data from wheat (PP#7F4864; DP# 249657, 1/25/99, D.
Dotson), and the 30 ppm tolerance was based on aspirated grain fraction
data from soybean seed (PP#9F6058; DP# 260134, 9/26/00, M. Nelson). 
Since it is Agency policy to establish a tolerance for aspirated grain
fraction based on the RAC with the highest residues in the dust, the
appropriate tolerance for aspirated grain fractions is 420 ppm.  A
revised Section F is required at 420 ppm for aspirated grain fractions. 

Note to PM:  The currently listed 10 and 30 ppm tolerances for this RAC
should be removed and replaced with this recommended tolerance level.  

Wheat

PP#6F4762, DP#s 230634, 230635, 230636 and 230637, 4/25/97, L. Kutney 

PP#7F4864, DP# 249657, 1/25/99, D. Dotson

46924303.der.doc (wheat)

Syngenta Crop Protection, Inc. has submitted field trial data for
azoxystrobin on wheat forage.  Twenty wheat field trials were conducted
in the United States in Zones 2 (NC; 1 trial), 4 (AR; 1 trial), 5 (IL,
KS, MN, MO, ND; 5 trials), 6 (OK; 1 trial), 7 (MT, NE, ND, SD; 5
trials), (CO, KS, NM, OK, TX; 6 trials), and 11 (WA; 1 trial) between
the 2004-2005 growing seasons.

Each trial consisted of one untreated plot and one treated plot.  Stands
of wheat received two foliar broadcast applications of a 2.08 lb/gal FlC
formulation of azoxystrobin at 0.24-0.27 lb ai/A/application, with 6- to
10-day retreatment intervals, for a total rate of 0.49-0.52 lb ai/A
(1.2-1.3x the maximum proposed seasonal rate of 0.4 lb ai/A).  All
applications were made using ground equipment in spray volumes of 2-20
gal/A with an adjuvant added to the spray solutions.  Wheat forage was
collected 12-15 days DALA and additional samples were collected from
three trial sites at 0, 7 and 21 DALA to generate residue decline data. 

Samples of wheat forage were analyzed for residues of azoxystrobin and
its Z-isomer (R230310) using LC/MS/MS Method RAM 305/03.  The validated
LOQ was 0.01 ppm for each analyte and the reported LOD was 0.005 ppm. 
The method was adequate for data collection based on acceptable
concurrent method recoveries.

Wheat forage samples were stored frozen (<-20°C) prior to analysis for
up to 12.2 months.  Adequate storage stability data are available to
support the storage conditions and durations of samples from the wheat
forage field trials.

A summary of residue data from the wheat field trials is presented in
Table 9.  Maximum residues of azoxystrobin and R230310, respectively,
were 11.0 and 0.43 ppm in/on wheat forage harvested 12-15 days following
two foliar applications for a total rate of 0.49-0.52 lb ai/A; maximum
combined residues (azoxystrobin + R230310) were 11.43 ppm in/on wheat
forage. 

Table 9.   Summary of Residue Data from Wheat Field Trials with
Azoxystrobin.

Commodity	Total Applic. Rate

 (lb ai/A)	PHI (days)	Combined Residue Levels of Azoxystrobin and its
Z-Isomer (ppm) 

	n	Min.	Max.	HAFT	Median

(STMdR)	Mean

(STMR)	Std. Dev.

Proposed Use Pattern:  Maximum seasonal rate of 0.40 lb ai/A with a
14-day PHI for forage and hay and a 45-day PHI for grain and straw.

Wheat forage	0.49-0.52	12-15	40	<0.02	11.43	8.79	0.64	1.86	2.55

The residue decline data indicated that residues of azoxystrobin and
R230310 generally declined in/on wheat forage with later sampling
intervals.

Conclusions:  The submitted residue data for wheat forage are adequate. 
The field trials were conducted according to the proposed use pattern,
and there is adequate geographic representation of data.  The field
trial data for wheat forage were entered into the Agency’s tolerance
spreadsheet as specified by the Guidance for Setting Pesticide
Tolerances Based on Field Trial Data SOP to determine an appropriate
tolerance level; see Appendix I.  The tolerance spreadsheet recommends a
tolerance of 25 ppm for wheat forage.  An amended Section F is required
to revise the proposed tolerance for wheat forage from 30 ppm to 25 ppm.

Azoxystrobin tolerances for wheat grain (0.10 ppm), hay (15 ppm), and
straw (4.0 ppm) have been established.  These tolerances are supported
by adequate residue data, which were presented in PP#6F4762 (DP#s
230634, 230635, 230636 and 230637, 4/25/97, L. Kutney) and subsequently
re-evaluated in PP#7F4864 (DP# 249657, 1/25/99, D. Dotson).  The
requirements for data on aspirated grain fractions of wheat are
fulfilled.

Cotton

47096402.de1.doc (cotton)

Syngenta Crop Protection, Inc. has submitted field trial data for
azoxystrobin on cotton.  Twelve cotton field trials were conducted in
the United States in Zones 2 (SC; 1 trial), 4 (AR, LA, MS; 3 trials), 6
(TX; 1 trial), 8 (NM, OK, TX; 4 trials), and 10 (CA; 3 trials) during
the 2005 growing season.

Each trial consisted of one untreated plot and one treated plot.  The
treated plot received one in-furrow application of a 2.08 lb/gal FlC
formulation of azoxystrobin at planting of cotton at a target rate 0.15
lb ai/A, followed by three foliar broadcast applications of the 2.08
lb/gal FlC formulation at a rate of 0.14-0.16 lb ai/A/application.  The
in-furrow rate treatment of 0.15 lb ai/A is equivalent to 0.5-1.9x the
proposed rate of 0.10-0.20 oz ai/1,000 row based on 22-40 inch row
spacing.  The total rate of 0.42-0.48 lb ai/A from foliar treatments is
1x the maximum seasonal rate for this use pattern.  The second
application (first foliar) was made as an over-the-top broadcast spray
64-126 days after the in-furrow at-planting application.  The following
two foliar applications were made with 9- to 12-day retreatment
intervals.  All treatments were made using ground equipment in spray
volumes of 5-15 gal/A, without an adjuvant.

Cottonseed was harvested 45 DALA, and samples from 6 trials (3 picker
harvested; 3 stripper harvested) were ginned for cotton gin byproducts
(trash).  Additional seed and gin byproduct samples were collected from
two trial sites 38 and 52 DALA to generate residue decline data. 

Samples of cottonseed and cotton gin byproducts were analyzed for
residues of azoxystrobin and its Z-isomer (R230310) using LC/MS/MS
Method RAM 305/03.  The validated LOQ was 0.01 ppm for each analyte and
the reported LOD was 0.005 ppm.  The method was adequate for data
collection based on acceptable concurrent method recoveries; however, it
is noted that the concurrent method validation fortification levels did
not encompass the maximum residues of azoxystrobin observed in treated
samples of cotton gin byproducts (31 ppm).

Samples were stored frozen (<-20°C) prior to analysis for up to 10
months for cottonseed and 11.1 months for cotton gin byproducts. 
Adequate storage stability data are available to support the storage
conditions and durations of the samples from the cotton field trials.

A summary of residue data from the cotton field trials is presented in
Table 10.  Maximum residues of azoxystrobin and R230310, respectively,
were 0.56 and 0.06 ppm in/on cotton undelinted seed, and 31 and 3.4 ppm
in/on cotton gin byproducts, harvested 45 days following an in-furrow at
planting application and three foliar applications for a total rate of
0.59-0.61 lb ai/A; maximum combined residues (azoxystrobin + R230310)
were 0.62 ppm in/on cottonseed and 34.4 ppm in/on cotton gin byproducts.
 

Table 10.   Summary of Residue Data from Cotton Field Trials with
Azoxystrobin.

Commodity	Total Applic. Rate

 (lb ai/A)	PHI (days)	Combined Residue Levels of Azoxystrobin and its
Z-Isomer (ppm) 

	n	Min.	Max.	HAFT	Median

(STMdR)	Mean

(STMR)	Std. Dev.

Proposed Use Pattern:  In-furrow application at planting at 0.1-0.2 oz
ai/1000 ft row + 3 postemergence foliar sprays at 0.15 lb
ai/A/application.  The proposed PHI is 45 days.

Cottonseed	0.59-0.61	45	24	<0.02	0.62	0.57	0.02	0.07	0.15

Cotton gin byproducts	0.59-0.61	45	12	<0.02	34.4	32.1	0.41	6.19	12

The residue decline data indicated that residues of azoxystrobin and
R230310 declined in/on cotton gin byproducts with later sampling
intervals.  Residues of azoxystrobin and R230310 were both low (near or
below the LOQ) in/on cottonseed from all sampling intervals.

Conclusions:  The submitted residue data for cotton commodities are
adequate to support an amended use pattern reflecting in-furrow
treatment at planting followed by multiple postemergence foliar
treatments; currently, only the in-furrow use pattern is registered. 
The field trials were conducted according to the proposed use patterns,
and there is adequate geographic representation of data.  The field
trial data for cottonseed and cotton gin byproducts were entered into
the Agency’s tolerance spreadsheet as specified by the Guidance for
Setting Pesticide Tolerances Based on Field Trial Data SOP to determine
appropriate tolerance levels; see Appendix I.  The tolerance spreadsheet
recommends tolerances of 0.60 ppm for undelinted cottonseed and 45 ppm
for cotton gin byproducts.  An amended Section F is required to revise
the proposed tolerances for undelinted cottonseed at 0.6 ppm and for
cotton gin byproducts at 45 ppm.

Wild rice

PP#7F4864, DP# 249657, 1/25/99, D. Dotson 

PP#9F6058 DP# 260134, 9/26/00, M. Nelson

No wild rice data were submitted to support the proposed tolerance for
the combined residues of azoxystrobin and its Z-isomer at 5.0 ppm.  The
petitioner indicated that previously reviewed rice data in PP#7F4864
should be translated to wild rice.   Although previous requests to
translate data were denied (PP#9F6058), ChemSAC (7/18/2007 minutes) now
recommends that rice grain data can be used to translate to wild rice
based on similarities in cultural practices.  The rice grain data may be
translated to support the requested tolerance for wild rice since the
use patterns of rice and wild rice are identical.  ARIA recommends for
the proposed tolerance of 5.0 ppm on wild rice.

860.1520 Processed Food and Feed

A sorghum processing study is not required for this action.  Table 1 of
OPPTS 860.1000 indicates that residue data are not needed at this time
for sorghum flour since it is used exclusively in the United States as a
component for drywall, and not as either a human food or a feedstuff. 
Acceptable wheat processing studies have also been submitted in
PP#6F4762 (DP#s 230634, 230635, 230636 and 230637, 4/25/97, L. Kutney)
and PP#7F4864 (DP# 249657, 1/25/99, D. Dotson).

Cotton

PP#9F06058, DP# 260134, 9/26/00, M. Nelson 

47096402.de2.doc (cotton)

Syngenta Crop Protection, Inc. has submitted a processing study with
azoxystrobin on cottonseed.  Samples used for processing were generated
from two trials conducted in TX during the 2005 growing season.  Each
trial consisted of one untreated plot, and one or two treated plots. 
One plot at both trial sites received one in-furrow application of a
2.08 lb/gal FlC formulation of azoxystrobin at crop planting at a target
rate of 0.75 lb ai/A, followed by three foliar broadcast applications at
0.72-0.78 lb ai/A/application, for a total rate of 3.02 lb ai/A (up to
5x the maximum proposed seasonal rate).  A second plot at one of the
trial sites was treated at the nominal field rate:  one in-furrow
application at 0.15 lb ai/A and three foliar broadcast applications at
0.14-0.15 lb ai/A/application, for a total rate of 0.59 lb ai/A.

The second application (first foliar) was made as an over-the-top
broadcast spray 94-100 days after the in-furrow at-planting application.
 The following two foliar applications were made with 9- to 11-day
retreatment intervals.  All treatments were made using ground equipment
in spray volumes of 5-22 gal/A, without an adjuvant.  Cottonseed was
harvested 45 days after the last application and then processed into
cotton hulls, meal, and refined oil using simulated commercial
practices.

Samples were stored frozen (~-20°C) prior to analysis for up to 9.7
months for cottonseed (RAC) and 4.6 months for processed cotton hulls,
meal, and refined oil.  Adequate storage stability data are available to
support the storage conditions and durations of the samples from the
cotton processing study.

Undelinted cottonseed and its processed commodities (hulls, meal, and
oil) were analyzed for residues of azoxystrobin and its Z-isomer
(R230310) using LC/MS/MS Method RAM 305/03.  The validated limit of
quantitation (LOQ) was 0.01 ppm for each analyte in all cotton matrices.
 The reported level of detection (LOD) was 0.005 ppm.  The method was
adequate for data collection based on acceptable concurrent method
recoveries and the processed commodities were only validated at the LOQ.

A summary of residue data from the cotton processing study is presented
in Table 11.  

At the Wharton, TX trial, average residues of azoxystrobin and R230310,
respectively, were 0.05 and <0.01 (below the LOQ) ppm in/on cottonseed
(RAC) treated with an in-furrow at-planting spray and three foliar
applications for a total rate of 3.02 lb ai/A; combined average residues
(azoxystrobin + R230310) were <0.06 ppm.  Based on the processing
results, residues of azoxystrobin do not appear to concentrate in hulls,
meal, and refined oil processed from cottonseed bearing low but
quantifiable residues; average processing factors were 0.9x, 0.3x, and
0.5x in cotton hulls, meal, and refined oil, respectively.  Residues of
R230310 were below the method LOQ in both the RAC and processed
commodities.  

At the Edmonson, TX trial, average residues of azoxystrobin were 0.02
ppm in/on cottonseed (RAC) treated with an in-furrow at-planting spray
and three foliar applications for a total rate of 0.59 lb ai/A.  Based
on the processing data, residues of azoxystrobin did not appear to
concentrate in hulls, meal and refined oil with processing; average
processing factors were 0.9x, <0.4x, and 0.4x in cotton hulls, meal, and
refined oil, respectively.  Residues of R230310 were below the method
LOQ in the RAC; therefore, samples from the exaggerated rate study (3.02
lb ai/A) were used for analysis of the R230310 residues.  Average
residues of R230310 were 0.035 ppm in the RAC and the residues did not
concentrate in hulls (0.6x), meal (<0.3x), or refined oil (<0.3x) with
processing.

Table 11.   Residue Data from Cotton Processing Study with Azoxystrobin.

Location

(City, State; Year)

Trial ID	Processed 

Commodity	Total Rate

(lb ai/A) 	PHI

(days)	Residues (ppm)	Processing 

Factor

Azoxystrobin	R230310	Combined Residues

	Wharton, TX; 2005

(SA-FR-05-6019)	Undelinted seed (RAC)	3.02	45	0.04

0.06	Not analyzed	--	--

0.03

0.07	<0.01

<0.01	<0.04

<0.08	--

	Cotton Hulls

	0.06

0.02	<0.01

<0.01	<0.07

<0.03	1.2x

0.5x

	Cotton Meal

	<0.01

<0.01	<0.01

<0.01	<0.02

<0.02	0.3x

0.3x

	Refined Oil

	0.02

0.02	<0.01

<0.01	<0.03

<0.03	0.5x

0.5x

Edmonson, TX; 2005

(SC-FR-05-6021)	Undelinted seed (RAC)	0.59	45	0.02

0.03

0.02

0.02	<0.01

<0.01

<0.01

<0.01	<0.03

<0.04

<0.03

<0.03	--

	Cotton Hulls

	0.02

0.02	Not

analyzed	--	0.9x

0.9x

	Cotton Meal

	<0.01

<0.01	Not

analyzed	--	<0.4x

<0.4x

	Refined Oil

	0.01

0.01	Not

analyzed	--	0.4x

0.4x

	Undelinted seed (RAC)	3.02	45	not

analyzed	0.02

0.05	--	--

	Cotton Hulls

	not

analyzed	0.02

0.02	--	0.6x

0.6x

	Cotton Meal

	not

analyzed	<0.01

<0.01	--	<0.3x

<0.3x

	Refined Oil

	not

analyzed	<0.01

<0.01	--	<0.3x

<0.3x

The observed processing factors did not exceed the theoretical
concentration factors based on separation into components (OPPTS
860.1520, Table 3) for cottonseed hulls (3.8x), meal (2.2x) and oil
(6.3x).

Conclusions:  The submitted cotton processing study is acceptable.  The
results indicate that the combined residues of azoxystrobin and its
Z-isomer did not concentrate in cotton meal, hulls, or refined oil
processed from undelinted cottonseed treated at up to 5x the maximum
proposed seasonal rate.  The results of this study are consistent with
another cottonseed processing study (MRID 44915231) reviewed in
PP#9F6058 (DP# 260134, 9/26/00, M. Nelson).  No tolerances are required
for the processed commodities of cotton.

  SEQ CHAPTER \h \r 1 860.1650 Submittal of Analytical Reference
Standards

Analytical standards for azoxystrobin and its Z-isomer metabolite are
currently available in the EPA National Pesticide Standards Repository
(personal communication with Dallas Wright, ACB, 8/8/07).  Standard
should be supplied as requested by the repository.

860.1850 Confined Accumulation in Rotational Crops

PP#6F4762, DP#s 230634, 230635, 230636 and 230637, 4/25/97, L. Kutney 

PP#9F6058, DP# 260134, 9/6/00, M. Nelson

  SEQ CHAPTER \h \r 1 Adequate confined studies have previously been
presented in PP#6F4762 and re-evaluated in PP#9F6058.  TRR, expressed as
[14C]azoxystrobin equivalents, accumulated at >0.01 ppm in the RACs of
lettuce, radishes, and wheat planted in sandy loam soil 30, 200, and 365
DAT of the soil with [14C]azoxystrobin at 1.8 lb ai/A.  Residues were
highest in RACs from the 30-DAT interval and declined in subsequent
plantback intervals.

Azoxystrobin was identified in all RACs at the 30-DAT interval.  In
30-DAT samples, the Z-isomer was only identified in wheat forage and
straw.  Compound 42 was the major metabolite identified in 30-DAT
lettuce and wheat forage and straw.  In 30-DAT radish roots,
azoxystrobin was the major metabolite and in 30-DAT radish tops,
metabolites G2, N1, and N2 were the major metabolites.  In 30-DAT wheat
grain, 14C-starch was found to account for the largest portion of
radioactivity.  Several conjugated metabolites (compound 42 and the M,
N, and O metabolites) of primary crop metabolites were identified,
indicating that azoxystrobin is more extensively metabolized in
rotational crops than in primary crops.  The residues of concern in
rotational crops are parent and the Z-isomer.

860.1900 Field Accumulation in Rotational Crops

PP#6F4762, DP#s 230634, 230635, 230636 and 230637, 4/25/97, L. Kutney 

PP#9F6058, DP#s 283588 and 287062, 2/6/03, N. Dodd

PP#9F6058, DP# 298114, 12/20/05, L. Cheng 

Limited field rotational crop studies, with applications made at 0.8 lb
ai/A seasonal rate to the primary crop, were initially submitted in
PP#6F4762.  Subsequently, additional limited field rotational crop
studies, with applications made at 1.6 or 2.0 lb ai/A seasonal rate to
the primary crop, were submitted and reviewed in PP#9F6058.

The results of the limited field accumulation study (MRID 45640307)
indicate that residues of azoxystrobin and its Z-isomer (R230310) will
not occur in mustard greens, turnip roots, turnip tops, and wheat grain
planted 36 days after application of azoxystrobin, as an 80% water
dispersible granular formulation, to a primary crop at a rate of 1.6 lb
ai/A/season.  This study also indicated that small amounts of residues
of azoxystrobin per se may occur in/on wheat matrices other than grain
at a plantback interval of approximately 60 days after treatment (i.e.,
0.02 ppm in wheat forage at 61 DAT; 0.01 ppm in wheat hay at 45 DAT;
0.04 ppm in wheat straw at 59 DAT).  No residues of the Z-isomer
(R230310) were found in any matrix at any plantback interval. 

In the other limited field accumulation study (MRID 45872401),   SEQ
CHAPTER \h \r 1 Azoxystrobin 80 WG (water dispersible granules) and 2.08
SC (flowable concentrate) were applied to the primary crop, leaf
lettuce, as six foliar broadcast sprays for a total of 2.0 lb ai/A (~1x
the maximum proposed/established seasonal rate for rotated crops).  The
rotational crops of leaf lettuce, garden beets, and wheat were planted
at plantback intervals of 30 and 60 days.  For crops planted 30 days
posttreatment, residues of parent were 0.03-0.13 ppm in/on wheat forage
samples, 0.02-0.12 ppm in/on hay samples, 0.09-0.18 ppm in/on straw
samples, and <0.01 ppm in/on grain samples; <0.01-0.01 ppm in/on leaf
lettuce; and <0.01 ppm in/on garden beet tops and roots.  For crops
planted 60 days posttreatment, residues of parent were 0.02-0.21 ppm
in/on wheat forage, 0.02-0.11 ppm in/on hay, 0.03-0.19 ppm in/on straw,
and <0.01 ppm in/on grain; <0.01-0.02 ppm in/on leaf lettuce; and <0.01
ppm in/on garden beet tops and roots.  Residues of R230310 were all
<0.01 ppm except in wheat straw; in wheat straw, residues of R230310
ranged from <0.01 to 0.01 ppm at plant-back intervals of 30 or 60 days.

The supplemental label for the Abound® Flowable Fungicide, submitted in
conjunction with PP#6F7106, includes the following restrictions listed
under the General Use Precautions: “Do not plant the following crops
for a period of 12 months (unless an azoxystrobin product is registered
for use on that crop): buckwheat, millet, oats and rye.  A plantback
interval of 36 days is required for leafy vegetables (except Brassica)
group; Brassica, leafy greens subgroup; vegetables, root subgroup;
vegetable (tuberous and corm subgroup; and vegetables, leaves of root
and tuber group.  Azoxystrobin is registered for use on all other
rotated crops, and all other crops may be planted immediately after the
last treatment.”  This is a revision of the rotational crop
restrictions on the currently registered label dated 2/23/2007, to
remove the 12-month PBI restriction for barley, nongrass animal feeds
(alfalfa and clover), sorghum, triticale, wheat, and wild rice.

Conclusions:  There are adequate field rotational crop data to support
the established rotational crop restrictions on the product labels.  As
tolerances on the commodities of primary crops (barley, nongrass animal
feeds (alfalfa and clover), sorghum, and wheat) are being proposed, the
rotational crop restrictions for these crops are no longer required.

860.1550 Proposed Tolerances

No residue data for barley forage were submitted to support the
requested tolerance of 30 ppm for this commodity.  Since the use
patterns of wheat and barley are identical, the available data for wheat
forage may be translated to barley forage pending submission of revised
Section F to specify a tolerance level of 25 ppm.

The submitted residue data for alfalfa and clover, the representative
crops of nongrass animal feeds, crop group 18, are adequate.  The field
trial data for alfalfa and clover forage and hay were entered into the
Agency’s tolerance spreadsheet as specified by the Guidance for
Setting Pesticide Tolerances Based on Field Trial Data SOP to determine
appropriate tolerance levels; see Appendix I.  The tolerance spreadsheet
recommends tolerances of 45 ppm for forage and 120 ppm for hay of the
nongrass animal feeds, crop group 18.  A revised Section F is required
to reflect these tolerance recommendations.

The submitted residue data for sorghum are inadequate because they do
not fully reflect the proposed use patterns.  The residue data only
reflect the proposed use pattern for postemergence foliar applications
and did not reflect the in-furrow treatment.  Although it is likely that
the bulk of residues will result from foliar uses, residue data
reflecting the complete use patterns (in-furrow + foliar) are required
since azoxystrobin is a systemic fungicide.  The field trial data for
sorghum forage, grain, and stover were entered into the Agency’s
tolerance spreadsheet to determine appropriate temporary tolerance
levels.  The tolerance spreadsheet recommends tolerances of 25 ppm for
sorghum forage, 11 ppm for sorghum grain, and 40 ppm for sorghum stover.
 An amended Section F is required to revise the proposed tolerance for
sorghum grain from 9 ppm to 11 ppm.

The field trial data for the aspirated grain fractions of sorghum from
bulk samples treated at 1x for foliar treatment showed that the combined
residues of azoxystrobin and its Z-isomer were 110.6 ppm; the combined
residues concentrated 49.4x.  Based on a processing factor of 49.4x and
the HAFT residue for sorghum grain (8.46 ppm), the expected residues in
the aspirated grain fractions of sorghum is 417.9 ppm.  It is noted that
40 CFR §180.507(a)(1) currently lists two tolerances for aspirated
grain fractions.  The 10 ppm tolerance was based on aspirated grain
fraction data from wheat (PP#7F4864; DP# 249657, 1/25/99, D. Dotson),
and the 30 ppm tolerance was based on aspirated grain fraction data from
soybean seed (PP#9F6058; DP# 260134, 9/26/00, M.J. Nelson).  Since it is
Agency policy to establish a tolerance for aspirated grain fraction
based on the RAC with the highest residues in the dust, the appropriate
tolerance for aspirated grain fractions is 420 ppm.  The currently
listed 10 and 30 ppm tolerances for this RAC should be removed and
replaced with this recommended tolerance level.  

The submitted residue data for wheat forage are adequate.  The field
trial data for wheat forage were entered into the Agency’s tolerance
spreadsheet to determine an appropriate tolerance level.  The tolerance
spreadsheet recommends a tolerance of 25 ppm for wheat forage.  An
amended Section F is required to revise the proposed tolerance for wheat
forage from 30 ppm to 25 ppm.

The submitted residue data for cotton commodities are adequate.  The
field trial data for cottonseed and cotton gin byproducts were entered
into the Agency’s tolerance spreadsheet to determine appropriate
tolerance levels.  The tolerance spreadsheet recommends tolerances of
0.60 ppm for undelinted cottonseed and 45 ppm for cotton gin byproducts.
 An amended Section F is required to revise the proposed tolerances for
undelinted cottonseed from 0.7 ppm to 0.6 ppm and for cotton gin
byproducts from 35 ppm to 45 ppm.

No wild rice data were submitted to support the establishment of the
proposed RAC tolerance at 5.0 ppm.  Since the use patterns of rice and
wild rice are identical, the available data for rice grain may be
translated to wild rice grain to support the proposed tolerance.

The submitted cotton processing study indicate that the combined
residues of azoxystrobin and its Z-isomer did not concentrate in cotton
meal, hulls, or refined oil processed from undelinted cottonseed treated
at up to 5x the maximum proposed seasonal rate.  No tolerances are
needed for the processed commodities of cotton.

No tolerances are required for inadvertent of azoxystrobin residues of
concern in/on rotational crops.  There are adequate rotational crop
restrictions on registered and proposed product labels which preclude
the need for tolerances.

The existing azoxystrobin tolerances for the milk, fat, meat, and meat
byproducts of ruminants were reassessed to account for the potential
increase in dietary exposure levels as a result of the proposed/amended
uses.  Reassessment of tolerances indicates that no increases in the
existing tolerances for milk and fat, meat and meat by products of
ruminants and swine are necessary.

The proposed and amended uses of azoxystrobin on the poultry feed items
are not expected to alter the Agency’s previous conclusion that there
is no reasonable expectation of finite residues in poultry commodities
[Category 3 of §180.6(a)].  No tolerances are needed for poultry and
eggs.  

No Codex MRLs have been established for azoxystrobin.  Canadian MRLs
have been established for residues of (αE)-methyl
2-[[6-(2-cyanophenoxy)-4-pyrimidinyl]oxy]-α
-methoxymethylene)benzeneacetate, including the isomer (Z)-methyl
2-[[6-(2-

cyanophenoxy)-4-pyrimidinyl]oxy]--(methoxymethylene)benzeneacetate in
livestock commodities; no MRLs have been established for the requested
crops.  Mexican MRLS have also been established for residues of
‘azoxistrobin’; however, no MRLs have been established for the
requested crops.

A summary of the recommended tolerances for the current petitions is
presented in Table 12.  The proposed tolerances should be revised to
reflect the recommended tolerance levels and correct commodity
definitions as specified in Table 12.  

Table 12.   Tolerance Summary for Azoxystrobin.

Commodity	Established Tolerance (ppm)	Proposed Tolerance (ppm)
Recommended Tolerance (ppm)	Comments; Correct Commodity Definition

Tolerances Proposed Under PP#6F7106 for 40 CFR §180.507(a)(1)

Aspirated grain fractions	10 & 30	112	420	The listed 10 (based on wheat)
and 30 (based on soybean) ppm tolerances for this RAC should be removed
and replaced with this recommended tolerance level.

Grain, aspirated fractions

Barley, forage	--	30	25

	Non-grass Animal Feeds

--Forage	--	35	45	Animal feed, nongrass, forage, group 18

Non-grass Animal Feeds

--hay	--	100	120	Animal feed, nongrass, hay, group 18

Sorghum – forage	--	25	25	Sorghum, grain, forage

Sorghum – grain	--	9	11	Sorghum, grain

Sorghum – stover	--	40	40	Sorghum, grain, stover

Wheat – forage	--	30	25	Wheat, forage

Tolerances Proposed Under PP#6F7106 for 40 CFR §180.507(a)(2)

Cattle, fat	0.03	0.13	0.03

	Cattle, kidney	--	1.00	Not needed; covered by tolerance for meat
byproducts

	Cattle, liver	--	5.10

Cattle, meat	0.01	0.07	0.01

	Cattle, meat byproducts (except liver and kidney)	0.07	0.07	0.07
Cattle, meat byproducts

Goat, fat	0.03	0.13	0.03

	Goat, kidney	--	1.00	Not needed; covered by tolerance for meat
byproducts

	Goat, liver	--	5.10

Goat, meat	0.01	0.07	0.01

	Goat, meat byproducts (except liver and kidney) 	0.07	0.07	0.07	Goat,
meat byproducts

Egg White	--	0.01	Not needed

	Egg Yolk	--	0.15

Hog, fat	0.010	1.10

Hog, kidney	--	0.03	Not needed

	Hog, liver	--	0.23

Hog, meat	0.01	0.01	Revoke; not needed

	Hog, meat byproducts (except liver and kidney) 	0.010	0.01	0.01	Hog,
meat byproducts

Horse, fat	0.03	--	0.03

	Horse, kidney	--	1.00	Not needed; covered by tolerance for meat
byproducts

	Horse, liver	--	5.10

Horse, meat	0.01	0.07	0.01

	Horse, meat byproducts	0.07	0.07	0.07

	Milk	0.006	0.05	0.006

	Poultry, Fat	--	0.01	Not needed

	Poultry, Liver	--	0.12

Poultry, Meat	--	0.02

Sheep, fat	0.03	0.13	0.03

	Sheep, kidney	--	1.00	Not needed; covered by tolerance for meat
byproducts

	Sheep, liver	--	5.10

Sheep, meat	0.01	0.07	0.01

	Sheep, meat byproducts (except liver and kidney)	0.07	0.07	0.07	Sheep,
meat byproducts

Tolerances Proposed Under PP#7F7198 for 40 CFR §180.507(a)(1)

Cotton, undelinted seed	0.02	0.7	0.6

	Cotton, gin byproducts	0.02	35.0	45

	Wild rice	--	5.0	5.0	Rice, wild, grain

References

DP#s:		318318 and 218448

Subject:	PP No. 5F4541:  New Chemical:  Azoxystrobin (ICIA5504) in/on
Grape RACs.  Evaluation of Analytical Methods and Residue Data.

From:		J. Garbus

To:		J. Bazuin/C. Giles-Parker

Dated:		03/19/96

MRIDs:	43678102-07, 43678193-95, 43678200-10 and 43694201-06

DP#s:		230634, 230635, 230636, and 230637

Subject:	PP#6F4762.  Azoxystrobin.  Permanent Tolerance Petition for Use
on Bananas, Peaches, Peanuts, Tomatoes, and Wheat.  Evaluation of
Analytical Methodology and Residue Data.

From:		L. Kutney

To:		C. Giles-Parker/J. Bazuin

Dated:		04/25/97

MRIDs:	44058715-30, 44058732-36, and 44073203-05

DP#s:		248887 and 249671

Subject:	PP#7F4864.  Tolerance Petition for use of Azoxystrobin on
Cucurbits. AND PP#8F4995.  Tolerance Petition for use of Azoxystrobin on
Bananas, Potatoes, and Stone Fruits.

From:		D. Dotson

To:		C. Giles-Parker/J. Bazuin

Dated:		10/14/98

MRIDs:	44319305, 44452303, 44595105, 44595109-11, 44595114, 44595116,
44613501 and 44613503

DP#:		250297

Subject:	PP#8F4995 and PP#7F4864.  Azoxystrobin (Abound Fungicide, EPA
Reg. No. 10182-415) in or on Canola, Wheat, Peanuts, Tree Nuts, and
Rice.  Briefing Memorandum for Metabolism Assessment Review Committee.

From:		W. Wassell

To:		G. Kramer, MARC

Dated:		11/06/98

MRIDs:	None

DP#:		251683	

Subject:	Azoxystrobin.  Conclusions of the Metabolism Assessment Review
Committee at Meeting of 11/10/98.

From:		W. Wassell

To:		G. Kramer, MARC

Dated:		12/30/98

MRIDs:	None

DP#s:		249657 and 249668

Subject:	PP# 7F4864.  Tolerance Petition for use of Azoxystrobin on
Peanut Hay, Pistachios, Rice, Tree Nuts, and Wheat. AND PP# 8F4995. 
Tolerance Petition for use of Azoxystrobin on Canola.

From:		D. Dotson

To:		C. Giles-Parker/J. Bazuin

Dated:		01/25/99

MRIDs:	44319303, 44319304, 44319306-08, 44452303, 44595104-08, 44595113,
44595115 and 44613502

DP#:		260134

Subject:	PP#9F06058:  Azoxystrobin.  Evaluation of Residue Chemistry
Data to Support Permanent Tolerances for Use of Azoxystrobin on Barley,
Bulb Vegetables, Cilantro, Citrus Fruits, Corn, Cotton, Leafy Vegetables
(Except Brassica), Leaves of Root and Tuber Vegetables, Peanuts, Root
and Tuber Vegetables, Soybeans, and Wild Rice; Higher Tolerances for the
Fat and Meat Byproducts of Cattle, Goats, Horses and Sheep; and, apples
(Inadvertant Residues).

From:		M.J. Nelson

To:		J. Bazuin/C. Giles-Parker

Dated:		09/06/00

MRIDs:	44915206-32 and 44983101

DP#:		278801

Subject:	Azoxystrobin.  Registration on Legume Vegetables, a Tolerance
for Imported Hops, and a Nonfood Use on Sunflowers.  Summary of
Analytical Chemistry and Residue Data.

From:		N. Dodd

To:		J. Bazuin/C. Giles-Parker

Dated:		07/31/02

MRIDs:	45221601-08, 45221610, 45287501 and 45287502

DP#s:		283588 and 287062

Subject:	PP#9F06058 and ID#s 000100-01098 and 000100-01093. 
Azoxystrobin.  Condition-of-Registration Data, Including Bridging Data
from the 50 WDG Formulation to the 2.08 FlC Formulation on Spinach,
Garden Beet, Green Onion and Celery; Storage Stability Data; and Limited
Field Rotational Crop Data.

From:		N. Dodd

To:		J. Bazuin/C. Giles-Parker

Dated:		02/06/03

MRIDs:	45640301, 45640302, 45640304-07, and 45738101

DP#:		298114

Subject:	Azoxystrobin.  Heritage Fungicide (EPA Reg. No. 100-1093. 
Condition-of-Registration Data:  Limited Field Rotational Crop Data. 
Petition Number 9F6058.

From:		L. Cheng

To:		J. Bazuin/C. Giles-Parker

Dated:		12/20/05

MRIDs:	45872401

DP#s:		312949, 312951, 312953 and 317291	

Subject:	Azoxystrobin Use on Dill, Chive, Sunflowers, Canola, and
Post-Harvest Citrus.  Review of Analytical Methods and Residue Data. 
Petition #s 3E6637, 3E6749, 4E6823 & 5E6916.

From:		W. Cutchin

To:		B. Madden/D. Rosenblatt

Dated:		1/23/06

MRIDs:	460069001, 46046601-04, 46219201, and 46509101

DP#:		328984

Subject:	Azoxystrobin.  Uses on Foliage of Legume Vegetables, Group 7;
Fruiting Vegetables, Group 8 (Except Tomato); Pea and Bean, Succulent
and Dried Shelled (Except Soybeans), Subgroups 6B and 6C; and Nongrass
Animal Feeds, Group 18.  Summary of Analytical Chemistry and Residue
Data.  Petition Number 4E6823.

From:		W. Cutchin

To:		S. Jackson/D. Rosenblatt

Dated:		6/19/06

MRIDs:	None

  SEQ CHAPTER \h \r 1 Attachments:  

International Residue Limit Status sheet

Appendix I - Tolerance Assessment Calculations

Template Version September 2005



INTERNATIONAL RESIDUE LIMIT STATUS

Chemical Name:  methyl(E)-2-(2-(6-(2-cyanophenoxy)
pyrimidin-4-yloxy)phenyl)-3-methoxyacrylate	Common Name:

Azoxystrobin	X Proposed tolerance

X Reevaluated tolerance

√ No Codex proposal step 6 or above

⁯ No Codex proposal step 6 or above for the crops requested	Petition
Numbers:  PP#6F7106 & PP#7F7198

DP#s:  334571 & 340016

Other Identifier:  

Residue definition (step 8/CXL):  N/A	Reviewer/Branch:  Barry O’Keefe,
RAB3

	Residue definition in PP#6F7106 and PP#7F7198 for plant commodities: 
Combined residues of azoxystrobin and its Z-isomer

   No Limits

√   No Limits for the crops requested, but see for livestock
commodities.	   No Limits

√   No Limits for the crops requested

Residue definition  (αE)-methyl
2-[[6-(2-cyanophenoxy)-4-pyrimidinyl]oxy]-α
-methoxymethylene)benzeneacetate,

including the isomer (Z)-methyl 2-[[6-(2-

cyanophenoxy)-4-pyrimidinyl]oxy]--(methoxymethylene)benzeneacetate
Residue definition:  Azoxistrobin

Crop(s)	MRL (mg/kg)	Crop(s)	MRL (mg/kg)

Liver of cattle, hogs, horses, and sheep	0.3

Kidney of cattle, hogs, horses, and sheep	0.06

Meat and meat-by-products of cattle, hogs, horses, and sheep	0.01

Notes/Special Instructions:  S. Funk, 08/08/2007.

Appendix I

Tolerance Assessment Calculations

es) and reasonably lognormal.  For datasets that were small (≤15
samples) and reasonably lognormal, the upper bound estimate of the 95th
percentile based on the median residue value was compared to the minimum
of the 95% UCL on the 95th percentile and the point estimate of the 99th
percentile, and the minimum value was selected as the tolerance value. 
For datasets that were not lognormal, the upper bound on the 89th
percentile was selected as the tolerance value (distribution-free
method).  The rounding procedures specified in the SOP were also used.

Cotton

The dataset used to establish a tolerance for azoxystrobin on cotton
commodities consisted of field trial data for undelinted cottonseed and
cotton gin byproducts, representing application rates of 0.59-0.61 lb
ai/A (one in-furrow at-planting application at 0.15 lb ai/A/application
and 3 foliar applications at 0.14-0.16 lb ai/A/application) with a
45-day PHI.  The in-furrow rate treatment of 0.15  lb ai/A is equivalent
to 0.5-1.9x the proposed rate of 0.10-0.20 oz ai/1,000 row based on
22-40 inch row spacing.  The total rate of 0.42-0.48 lb ai/A from foliar
treatments is 1x the maximum seasonal rate for this use pattern.  

The dataset for cottonseed included 24 samples.  Individual residues of
azoxystrobin and its Z-isomer (R230310) were below the LOQ in 11 and 22
of the 24 samples, respectively; eleven samples had total azoxystrobin
and R230310 residues below the combined LOQ.  Since >10-15% and ≤60%
of the total residues in/on cottonseed were below the combined LOQ,
maximum likelihood estimation (MLE) procedures were used to impute
censored values.

The dataset for cotton gin byproducts was small (12 samples). 
Individual residues of azoxystrobin and R230310 were below the LOQ in 1
and 2 of the 12 samples, respectively.  Since only one of the samples
had total azoxystrobin and R230310 residues below the combined LOQ, MLE
procedures were not needed to impute censored values.

The datasets were entered into the tolerance spreadsheet.  Visual
inspection of the lognormal probability plots, Figures I-1 and I-3,
provided in the spreadsheet indicated that the cotton gin byproduct
dataset was reasonably lognormal, but that the cottonseed dataset was
not.  The results from the approximate Shapiro-Francia test statistic
(Figures I-2 and I-4) confirmed that the assumption of lognormality
should not be rejected for cotton gin byproducts but should be rejected
for cottonseed.

Using the tolerance spreadsheet, the recommended tolerance for
cottonseed is 0.60 ppm.  For cotton gin byproducts, the spreadsheet
calculates a tolerance of 3.5 ppm when determined by the UPL Median 95th
percentile method and 45 ppm when determined by the California method. 
A tolerance of 3.5 ppm would not cover the maximum residues found at the
cotton field trials; therefore, the appropriate tolerance for cotton gin
byproducts is 45 ppm.

Table I-1.	Residue data used to calculate tolerances for azoxystrobin on
cottonseed and gin byproducts.

Regulator:	EPA

Chemical:	Azoxystrobin

Crop:	Cottonseed (MLE)	Cotton gin byproducts

PHI:	45 days	45 days

App. Rate:	0.59-0.61 lb ai/A

(1 in-furrow at-planting at 0.15 lb ai/A + 3 foliar at 0.14-0.16 lb
ai/A/application)

Submitter:	Syngenta Crop Protection, Inc.

MRID Citation:	MRID 47096402

	Combined Residues of Azoxystrobin and its Z-isomer

	0.0200	4.41

	0.0200	3.77

	0.0400	0.43

	0.0300	0.39

	0.0200	0.11

	0.0200	0.12

	0.0044	0.48

	0.0052	0.37

	0.0060	<0.02

	0.0070	<0.02

	0.0080	29.80

	0.0090	34.40

	0.0400

0.0400

0.0102

0.0115

0.0200

0.0300

0.5100

0.6200

0.0144

0.0400

0.0161

0.0179

	

Figure I-   SEQ Figure_II- \* ARABIC  1 .  Lognormal probability plot of
azoxystrobin field trial data for cottonseed.

Figure I- 2.   Tolerance spreadsheet summary of azoxystrobin field trial
data for cottonseed.

Figure I- 3.  Lognormal probability plot of azoxystrobin field trial
data for cotton gin byproducts.

Figure I- 4.   Tolerance spreadsheet summary of azoxystrobin field trial
data for cotton gin byproducts.

Crop Group 18: Nongrass Animal Feeds

The dataset used to establish a tolerance for azoxystrobin on the
nongrass animal feeds crop group consisted of field trial data for
clover and alfalfa, which are the representatives of crop croup 18.  The
clover dataset represents application rates of 0.73-0.77 lb ai/A (3
applications at 0.24-0.26 lb ai/A/application), with a 13- to 15-day
PHI.  The alfalfa datasets represent application rates of 0.50-0.51 lb
ai/A or 0.75-0.76 lb ai/A (2 or 3 applications at 0.24-0.26 lb
ai/A/application, respectively), with 13-14 PHI.  Both application rates
for alfalfa (representing second and third cuttings) were considered in
determining the recommended tolerances since residues were higher in
alfalfa hay following two applications than after three applications;
residues from the first cutting (one application at ~0.25 lb ai/A) were
the lowest and, therefore, were not considered.  As specified by the
SOP, the results used for tolerance calculation represented field trial
application rates and PHIs within 25% of the maximum label application
rate and minimum label PHI, respectively.  The residue values used to
calculate the tolerance are provided in Table I-2.

The clover dataset included 16 samples each for forage and hay. 
Residues of azoxystrobin and R230310 were above the LOQ in all clover
forage and hay samples.  The alfalfa datasets included 18 samples each
for forage and hay at each application rate.  Following two applications
to alfalfa, residues of azoxystrobin were above the LOQ in all forage
and hay samples, and residues of R230310 were above the LOQ in all hay
samples, but residues of R230310 were below the LOQ in 2 of the 18
forage samples.  Following three applications to alfalfa, residues of
azoxystrobin and R230310 were above the LOQ in all forage and hay
samples.  Because no clover or alfalfa samples had total azoxystrobin
and R230310 residues below the combined LOQ, MLE procedures were not
needed to impute censored values. 

The dataset for each crop matrix was entered into the tolerance
spreadsheet.  Visual inspection of the lognormal probability plots for
clover and alfalfa forage (Figures I-5, I-7 and I-9) and clover and
alfalfa hay (Figures I-11, I-13 and I-15) provided in the spreadsheet
indicated that the datasets were reasonably lognormal.  The results from
the approximate Shapiro-Francia test statistic confirmed that the
assumption of lognormality should not be rejected for clover and alfalfa
forage (Figures I-6, I-8 and I-10) or clover and alfalfa hay (Figures
I-12, I-14 and I-16).  

Using the tolerance spreadsheet, the recommended tolerances are 45 ppm
for clover forage and 120 ppm for clover hay.  The recommended
tolerances for alfalfa are 35 and 40 ppm for second and third cutting
forage, and 110 and 95 ppm for second and third cutting hay,
respectively; the recommended tolerances were highest for third cutting
forage and second cutting hay.  Because the recommended tolerances for
the forage and hay of clover and alfalfa differ by less than 5x between
crops, crop group tolerances for the forage and hay of nongrass animal
feeds are appropriate.  Based on the maximum recommended individual
tolerances, the recommended values are 45 ppm for forage and 120 ppm for
hay of the crop group.



Table I-2.	Residue data used to calculate tolerance for azoxystrobin on
nongrass animal feeds, crop group 18.

Regulator:	EPA

Chemical:	Azoxystrobin

Crop:	Clover forage	Clover hay	Alfalfa forage	Alfalfa hay	Alfalfa forage
Alfalfa hay

PHI:	13-15 days	13-14 days	13-14 days

App. Rate:	0.73-0.77 lb ai/A (3 at 0.24-0.26 lb ai/A/application)
0.50-0.51 lb ai/A (2 at 0.25-0.26 lb ai/A/application)	0.75-0.76 lb ai/A
(3 at 0.24-0.26 lb ai/A/application)

Submitter:	Syngenta Crop Protection, Inc.

MRID Citation:	MRID 46924301

	Combined Residues of Azoxystrobin and its Z-isomer

	3.37	7.29	<0.11	1.18	0.65	4.14

	3.99	8.47	<0.10	2.35	1.25	3.48

	7.10	23.81	0.26	0.56	<0.12	0.36

	5.57	20.75	0.21	0.46	0.16	0.27

	0.67	3.98	0.24	0.65	1.71	6.49

	0.64	3.51	0.25	1.27	2.11	6.70

	3.28	10.68	3.26	1.24	8.75	15.80

	6.21	13.92	2.09	2.63	8.21	14.84

	1.30	3.37	0.37	1.77	3.45	8.12

	1.07	3.72	0.51	1.46	3.01	7.89

	12.10	31.00	0.84	2.28	1.05	2.77

	14.30	27.60	0.80	3.16	1.06	2.23

	11.73	55.50	6.29	23.80	1.48	3.83

	16.00	39.70	6.13	25.65	1.49	3.41

	4.45	22.71	8.54	42.40	8.68	30.74

	4.44	18.66	5.35	45.30	8.03	21.59

	2.54	7.01	4.99	14.89

	3.06	9.81	3.80	7.86

Figure I- 5.  Lognormal probability plot of azoxystrobin field trial
data for clover forage.

Figure I- 6.   Tolerance spreadsheet summary of azoxystrobin field trial
data for clover forage.

Figure I- 7.  Lognormal probability plot of azoxystrobin field trial
data for alfalfa forage (second cutting).

Figure I- 8.   Tolerance spreadsheet summary of azoxystrobin field trial
data for alfalfa forage (second cutting).

Figure I- 9.  Lognormal probability plot of azoxystrobin field trial
data for alfalfa forage (third cutting).

Figure I- 10.   Tolerance spreadsheet summary of azoxystrobin field
trial data for alfalfa forage (third cutting).

Figure I- 11.  Lognormal probability plot of azoxystrobin field trial
data for clover hay.

Figure I- 12.   Tolerance spreadsheet summary of azoxystrobin field
trial data for clover hay.

Figure I- 13.  Lognormal probability plot of azoxystrobin field trial
data for alfalfa hay (second cutting).

Figure I- 14.   Tolerance spreadsheet summary of azoxystrobin field
trial data for alfalfa hay (second cutting).

Figure I- 15.  Lognormal probability plot of azoxystrobin field trial
data for alfalfa hay (third cutting).

Figure I- 16.   Tolerance spreadsheet summary of azoxystrobin field
trial data for alfalfa hay (third cutting).

Sorghum

The dataset used to establish the conditional tolerances for
azoxystrobin on sorghum commodities represents foliar application rates
of 0.49-0.51 lb ai/A (2 applications at 0.24-0.26 lb ai/A/application)
with a 14- to 15-day PHI for sorghum forage and 0.74-0.78 lb ai/A (3
applications at 0.24-0.26 lb ai/A/application) with a 13- to 17-day PHI
for sorghum grain and stover.  As specified by the SOP, the results used
for tolerance calculation represented field trial application rates and
PHIs within 25% of the maximum label application rate for foliar
application and minimum label PHI, respectively.  The residue values
used to calculate the tolerances are provided in Table I-3.

The sorghum datasets were not small (24 samples each of forage, grain
and stover).  All field trial sample results for residues of
azoxystrobin and R230310 were above the LOQ for sorghum forage, grain
and stover.  Because no sorghum sample had total residues of
azoxystrobin and R230310 below the combined LOQ, MLE procedures were not
needed to impute censored values.

The dataset for each crop was entered into the tolerance spreadsheet. 
Visual inspection of the lognormal probability plots (Figures I-17, I-19
and I-21) provided in the spreadsheet indicated that the datasets for
sorghum forage, grain and stover were reasonably lognormal.  The results
from the approximate Shapiro-Francia test statistic (Figures I-18, I-20
and I-22) confirmed that the assumption of lognormality should not be
rejected for forage, grain, and stover.

Using the tolerance spreadsheet, the recommended tolerances are 25 ppm
for sorghum forage, 11 ppm for sorghum grain, and 40 ppm for sorghum
stover.



Table I-3.	Residue data used to calculate tolerances for azoxystrobin on
sorghum.

Regulator:	EPA

Chemical:	Azoxystrobin

Crop:	sorghum forage	sorghum grain	sorghum stover

PHI:	14-15 days	13-17 days	13-17 days

App. Rate:	0.49-0.51 lb ai/A 

(2 at 0.24-0.26 lb ai/A/application)	0.74-0.78 lb ai/A 

(3 at 0.24-0.26 lb ai/A/application)

Submitter:	Syngenta Crop Protection, Inc.

MRID Citation:	MRID 46924302

	Combined Residues of Azoxystrobin and its Z-isomer

	0.39	1.43	0.48

	0.24	1.52	0.69

	2.03	3.35	2.32

	1.59	2.82	3.45

	0.20	2.46	7.58

	0.48	1.64	2.89

	0.35	1.77	4.75

	0.52	1.68	2.96

	0.29	1.21	0.63

	0.32	1.50	0.93

	4.31	1.38	4.52

	7.64	1.58	6.75

	5.41	1.84	0.38

	4.03	2.30	0.52

	2.70	4.96	15.90

	2.09	4.67	17.00

	0.38	0.38	1.72

	0.16	0.68	3.31

	2.03	2.44	6.05

	1.53	2.45	3.38

	1.01	8.35	3.16

	3.10	8.57	4.56

	10.00	2.33	7.52

	5.99	2.23	15.10

Figure I- 17.   Lognormal probability plot of azoxystrobin field trial
data for sorghum forage.

Figure I- 18.   Tolerance spreadsheet summary of azoxystrobin field
trial data for sorghum forage.

Figure I- 19.   Lognormal probability plot of azoxystrobin field trial
data for sorghum grain.

Figure I- 20.   Tolerance spreadsheet summary of azoxystrobin field
trial data for sorghum grain.

Figure I- 21.   Lognormal probability plot of azoxystrobin field trial
data for sorghum stover.

Figure I- 22.   Tolerance spreadsheet summary of azoxystrobin field
trial data for sorghum stover.

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ied by the SOP, the results used for tolerance calculation represented
field trial application rates and PHIs within 25% of the maximum label
application rate and minimum label PHI, respectively.  The residue
values used to calculate the tolerance are provided in Table I-4.

The wheat dataset was not small (40 forage samples).  Individual
residues of azoxystrobin and R230310 were below the LOQ in 2 and 12 of
the 40 samples, respectively.  Because only two samples had total
residues of azoxystrobin and R230310 below the combined LOQ, MLE
procedures were not needed to impute censored values. 

The datasets were entered into the tolerance spreadsheet.  Visual
inspection of the lognormal probability plot, Figure I-23, provided in
the spreadsheet indicated that the datasets were reasonably lognormal,
which was confirmed by the approximate Shapiro-Francia test statistic,
Figure I-24.

 

Using the tolerance spreadsheets, the recommended tolerance is 25 ppm
for wheat forage.

Table I-4.	Residue data used to calculate tolerance for azoxystrobin on
wheat forage.

Regulator:	EPA

Chemical:	Azoxystrobin

Crop:	wheat forage

PHI:	12-15 days

App. Rate:	0.49-0.52 lb ai/A (2 at 0.24-0.27 lb ai/A/application)

Submitter:	Syngenta Crop Protection, Inc.

MRID Citation:	MRID 46924303

	Combined Residues of Azoxystrobin and its Z-isomer

	0.47

	0.39

	1.36

	2.29

	1.15

	0.97

	3.84

	3.55

	1.57

	1.46

	0.14

	0.15

	0.47

	0.71

	0.41

	0.52

	0.06

	0.03

	0.22

	0.16

	0.16

	0.10

	1.94

	2.31

	2.62

	3.65

	6.66

	8.61

	6.14

	11.43

	0.57

	1.65

	0.40

	0.27

	0.08

	0.12

	0.02

	0.02

	3.43

	4.36

Figure I- 23.   Lognormal probability plot of azoxystrobin field trial
data for wheat forage.

Figure I- 24.   Tolerance spreadsheet summary of azoxystrobin field
trial data for wheat forage.

Page   PAGE  2  of   NUMPAGES  56 

Azoxystrobin	Summary of Analytical Chemistry and Residue Data	DP#s
334571 & 340016