UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON, D.C.  20460

OFFICE OF           

PREVENTION, PESTICIDES

AND TOXIC SUBSTANCES

MEMORANDUM

	Date:	February 6, 2007

	Subject:	Cymoxanil.  IR-4’s Request to Amend Tanos® DF Fungicide
(EPA Reg. No. 352-604) to Add New Uses on Grapes Grown East of the Rocky
Mountains, Hops and Caneberry.  Summary of Analytical Chemistry and
Residue Data.  PP#6E7100.

DP Num:	333252	Decision Number: 	361957

PC Code:	129106	MRID Nos.:	46670201, 46670202 and 46905901

40 CFR §180:	503(a)



Chemical Class:	Fungicide





	From:	Debra Rate, Ph.D., Biologist

		Alternative Risk Integration and Assessment (ARIA)

		Risk Integration, Minor Use, Emergency Branch (RIMUERB)

		Registration Division (RD) (7505P)

	Through:	William Cutchin, Acting Branch Senior Scientist

		ARIA

		Technical Review Branch (TRB)

		RD (7505P)

		

			And

		George F. Kramer, Ph.D., Senior Chemist

		Registration Action Branch 1 (RAB1)

		Health Effects Division (HED) (7509P)

	To:	Shaja Brothers

		RIMUER Branch

		Registration Division (RD) (7505P)

This document was originally prepared under contract by Dynamac
Corporation (submitted 7/14/2006).  The document has been reviewed by
the ARIA and revised to reflect current Office of Pesticide Programs
(OPP) policies.

Executive Summary

Cymoxanil is a broad-spectrum protectant fungicide with locally systemic
activities against downy mildew and late blight diseases.  Cymoxanil is
presently registered in the United States for food/feed uses on hops,
lettuce (head), potatoes, cucurbit vegetables, and fruiting vegetables. 
Although there are no U.S. registrations for grapes and lychees, import
tolerances are currently established for these raw agricultural
commodities.

Tolerances for residues of cymoxanil are listed in 40 CFR §180.503 and
are expressed in terms of cymoxanil per se.  Cymoxanil tolerances have
been established for grape (0.1 ppm without U.S. registration), dried
hop cones (1.0 ppm), head lettuce (4.0 ppm), lychee (1.0 ppm without
U.S. registration), potato (0.05 ppm), cucurbit vegetable (crop group 9;
0.05 ppm), and fruiting vegetable (crop group 8; 0.2 ppm).  No cymoxanil
tolerances for livestock commodities are listed in 40 CFR §180.503.

The   SEQ CHAPTER \h \r 1 Interregional Research Project No. 4 (IR-4)
has submitted a request for an amended registration of the end-use
product, Tanos® DF (EPA Reg. No. 352-604), a dry flowable formulation
containing 25% ai cymoxanil plus 25% ai famoxadone to include new
domestic uses of cymoxanil on grapes grown east of the Rocky Mountains,
on hops, and canberries.  Concurrently, IR-4 requests the establishment
of permanent tolerance for residues of the fungicide, expressed as
cymoxanil per se, as follows:

	Hops,
dried………………………………………………………….
5.0 ppm

	Grape…………………………………………………………
..........1.0 ppm

	Caneberry……………………………………………………
……...4.0 ppm

IR-4’s submission of supporting field trial data for grapes, hops and
caneberries contain residue data for both active ingredients (cymoxanil
and famoxadone).  This summary document addresses only the residue
chemistry data for cymoxanil; the residue chemistry data for famoxadone
will be handled in a separate document.

The currently established cymoxanil tolerance of 1.0 ppm for dried hop
cones was established through PP#1E06224.  The magnitude of the residue
data, that were submitted/reviewed for this petition, were generated
according to the following label use pattern for   SEQ CHAPTER \h \r 1
Curzate® 60 DF (EPA Reg. No. 352-592), a dry flowable formulation
containing 60% ai cymoxanil:  a maximum single foliar application rate
of 0.15 lb ai/A with a 14-day retreatment interval (RTI), a maximum
seasonal rate of 0.6 lb ai/A, and a 7-day preharvest interval (PHI).  In
the current request to amend Tanos® DF to add hops to the label, there
are discrepancies regarding the maximum single and seasonal rates listed
in Section B and the submitted specimen label.  ARIA is recommending
label revision of Tanos® DF to reflect the application rates (single
and seasonal), RTI, and PHI that were used in the hop field trials.

The petitioner’s request to amend Tanos® DF to add use of cymoxanil
and famoxadone on grapes grown east of the Rocky Mountains is not
supported by field trial data generated in the U.S.  However, according
to the Minutes of the 4/7/04 HED’s Chemistry Science Advisory Council
(ChemSAC) meeting,   SEQ CHAPTER \h \r 1 residue data generated in
Europe (France, Germany, Greece, and Spain) for use of cymoxanil plus
famoxadone on grapes could be translated to support use on grapes east
of the Rockies.  This determination was made following ChemSAC’s
discussions of climatic differences between Europe and regions east of
the Rockies, formulation differences (the European product contained 30%
cymoxanil and 22.5% famoxadone whereas the U.S. formulation contains 25%
of each fungicide), and grape production statistics.  The ChemSAC
concluded that translation of data is reasonable with the following
caveats:  (i) since the ratio of actives differs in the U.S. product,
the label directions need to ensure that the maximum application rate of
each fungicide is less than or equal to the corresponding rate in the
European trials; (ii) other use parameters such as the preharvest and
reapplication intervals also need to match the data; and (iii) the
petitioner needs to address any significant differences in the inert
ingredients of the two formulations.  If the U.S. product contains an
inert which can significantly increase the adherence or stability of the
residues, the data translation is not likely to be accepted. 

The ChemSAC confirmed the use of the European cymoxanil data to support
uses on grapes east of the Rocky Mountains for other active ingredients
(12/JUL/2006).

The currently established cymoxanil import tolerance of 0.10 ppm for
grape was established through PP#5E04504 and PP#7F04814.  The magnitude
of the residue data, that were submitted/reviewed for these petitions,
were generated according to the following use pattern for a European
water dispersible granular (WG) formulation of   SEQ CHAPTER \h \r 1
DPX-KX007 WG:   SEQ CHAPTER \h \r 1 a maximum single application rate of
0.107 lb ai/A (120 g ai/ha), a maximum of 12 applications per season
(for an implied seasonal rate of 1.28 lb ai/A) with a 7-10 day
retreatment interval, a minimum spray volume of 20 L/ha, and a minimum
PHI of 14 days.  Since no residue data from trials on grapes grown east
of the Rocky Mountains were included in the current petition and the
petitioner is relying on data generated from Europe, label revision is
required for Tanos® DF to comply with a previous regulatory conclusion
made by ChemSAC regarding translation of data.

The nature of the residue in grape, lettuce, potato, and tomato is
adequately understood.  In grapes, potatoes, and tomatoes, cymoxanil was
metabolized primarily into [14C]glycine and further incorporated into
the sugars fructose and glucose.  An ad hoc HED Metabolism Assessment
Review Committee (MARC) met on 1/21/98 to discuss the toxicological
significance of potential metabolites.  It was decided that only the
parent is of regulatory concern.  HED concluded that cymoxanil per se is
the only residue of concern for tomatoes, potatoes, and grapes.  Based
on this data and crop similarities, the tolerance expression for
cymoxanil on caneberry is also cymoxanil per se.  

 

  SEQ CHAPTER \h \r 1 Since the previous MARC meeting, the petitioner
submitted a lettuce metabolism study in conjunction with PP#1E06224.   
SEQ CHAPTER \h \r 1 Metabolites IN-KQ960 and IN-KP533 were identified in
the lettuce metabolism study but these metabolites were not detected in
the tomato, grape, or potato metabolism studies.  These results were
presented to the HED MARC on 07/AUG/2001 to assess the toxicological
significance of these metabolites and to determine which additional
residues, if any, to regulate.  The MARC determined that the nature of
the residue is understood in leafy vegetables.  For the plant metabolism
studies conducted to this point, the detection of metabolites IN-KQ960
and IN-KP533 is unique in lettuce.  The MARC concluded that for the
tolerance expression, the residue of concern in/on hops is cymoxanil per
se.  However, for risk assessment purposes, the residues of concern
in/on hops are cymoxanil plus the metabolite IN-KQ960 based on the ratio
(3.5:1) of IN-KQ960 to the parent in the lettuce 14C metabolism study.  

There are no livestock feedstuffs associated with the proposed use on
grapes, hops and caneberries.  Therefore, data requirements for
metabolism, residue analytical methods for livestock commodities,
storage stability data for livestock commodities, and animal feeding
studies are not relevant to this tolerance petition.

The requirements for data pertaining to confined/field accumulation in
crops are not germane to this petition because grapes, hops and
caneberries   SEQ CHAPTER \h \r 1 are crops typically not rotated.

There is an adequate enforcement method for grapes.  A high-performance
liquid chromatography with UV detection (HPLC/UV) method (AMR 3060-90
Revision No. 2) has been subjected to a successful validation by an
independent laboratory as well as by Agency chemists at Biological and
Economic Analysis Division/Analytical Chemistry Laboratory (BEAD/ACL) in
conjunction with the previous import tolerance petitions (PP#5E04504 and
PP#7F04814) for grapes and tomatoes.  The limit of quantitation (LOQ) of
the method was reported to be 0.05 ppm.  An enforcement method had also
been submitted for hops.  HED had requested ACL to determine whether the
hops method needed to undergo independent laboratory validation (ILV)
plus a petition method validation (PMV) route since preliminary
assessment by HED of the method showed that it differed from the
existing methodologies.  Since this request, a new enforcement method
had been submitted using HPLC/mass spectroscopy (MS).  The only major
change between the validated method and the newly submitted method is
the use of MS detection versus UV detection.  The validation data and
the enforcement method provided by the petitioner are adequate.

There is an adequate enforcement method for caneberry.  Caneberry
samples were analyzed for cymoxanil using a slightly modified version of
a Morse Laboratories and E.I. DuPont Nemours and Company method entitled
Analytical Method for the Determination of DPX-JE874 and Cymoxanil
Residues in Various Matrices.  The adapted method was titled Residue
Analysis of Cymoxanil on Caneberry by HPLC/UV, Version #1.  As mentioned
above, this method has been subjected to a successful ILV as well as
PMV.  The LOQ was 0.072 ppm and the LOD was 0.024 ppm for caneberry. 
The petitioner has previously submitted data pertaining to the FDA
Multiresidue Methods testing of cymoxanil in conjunction with the
imported grape and tomato tolerance petitions.  The data indicate that
cymoxanil was recovered using Protocol D which can, therefore, be used
as a confirmatory method.

The data-collection methods used for the analysis of grape, hop and
caneberry samples for cymoxanil are based on the approved/proposed
enforcement methods; these methods are adequate for data collection
based on acceptable method recoveries which were generally within the
acceptable range of 70-120%.

There are adequate storage stability data to support the integrity of
samples collected from field and processing studies.  Residues of
cymoxanil are stable under frozen storage conditions for up to 18 months
in/on grapes and it processed fractions (juice and dry pomace), 8.5
months in/on dried hops, and ~5 months in/on caneberries.  There are no
storage stability issues or corrections that need to be applied to the
various residue studies.

The results from the grape field trials show that residues of cymoxanil
were below the method LOQ (<0.04 ppm) in/on wine grapes harvested 28
days after the last of ten foliar spray applications at 1.197-1.462 lb
cymoxanil/A.  Residue decline data show that cymoxanil decreases in wine
grapes with increasing PHIs.

The results from the hop field trials show that the maximum residues of
cymoxanil were 4.07 ppm in/on dried hop cones harvested 7-8 days after
the last of six directed foliar applications at ~0.25 lb
ai/A/application for a total application rate of ~1.50 lb cymoxanil
(ai)/A.

The results from these trials show that cymoxanil residues ranged from
0.24 ppm to 2.2 ppm on/in treated caneberry when the test substance was
applied at the proposed seasonal application rate of 1.125 lb
cymoxanil/A using a 0-day PHI.  Caneberry was stored frozen for a
maximum of 154 days at –21ºC.  Submitted storage stability studies
indicate that cymoxanil residues are stable on caneberry for up to 216
days.  A residue decline study was not conducted by the petitioner.

The HED’s ChemSAC (see Minutes of the 07/APR/2004 ChemSAC meeting)  
SEQ CHAPTER \h \r 1 has previously determined that a grape processing
study is required to determine whether cymoxanil residues concentrate in
juice.  The ChemSAC also determined that data are not required for
raisins for a use limited to east of the Rocky Mountains.  A
subsequently submitted grape processing study indicates that cymoxanil
residues concentrate marginally in juice (processing factor of >1.4x). 
The observed processing factor and highest average field trial (HAFT) do
not warrant the establishment of a tolerance on juice because the
maximum expected residue of cymoxanil in juice is lower than the
recommended RAC tolerance.

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

  SEQ CHAPTER \h \r 1 ARIA concludes that there are no major residue
chemistry data requirements that would preclude IR-4’s amended
registration request for Tanos® DF (EPA Reg. No. 352-604) to add new
uses on hops, grapes grown east of the Rocky Mountains, and caneberries
pending tolerance adjustments and label revisions as recommended below. 


860.1200 Directions for Use

The directions for use shown on the draft label for use on caneberry are
consistent with the use directions utilized in the submitted field trial
studies.  No label amendments for Tanos® DF (EPA Reg. No. 352-604) are
required for this commodity.

Label amendments are required for Tanos® DF (EPA Reg. No. 352-604) to
reflect the parameters of field trial data for hops and to be consistent
with the HED’s ChemSAC determination regarding translation of residue
data for grapes.  

For hops, the label should be revised to specify a maximum single foliar
application rate of 0.25 lb ai/A with a 6-8 day RTI and a maximum
seasonal rate of 1.5 lb ai/A.  

For grapes grown east of the Rocky Mountains, the label should be
revised to be consistent with the ChemSAC’s determination that   SEQ
CHAPTER \h \r 1 residue data generated in Europe (France, Germany,
Greece, and Spain) for use of cymoxanil plus famoxadone on grapes could
be translated to support use on grapes east of the Rockies provided the
use patterns are identical or the use pattern is more restrictive (i.e.,
lower application rates and longer PHI).  Therefore, based on the
European field trial data, the proposed use on grapes grown east of the
Rocky Mountains should be revised to specify a maximum single
application rate of 0.107-0.125 lb ai/A, a maximum of 9 applications per
season (for an implied seasonal rate of 1.125 lb ai/A) with a 10-day
retreatment interval, and a PHI of 30 days.

ARIA defers to RD for examination of inert ingredients listed on Tanos®
DF.    SEQ CHAPTER \h \r 1 If Tanos® DF contains an inert which can
significantly increase the adherence or stability of the residues, the
residue data generated in Europe for use of cymoxanil plus famoxadone on
grapes could not be translated to support use on grapes east of the
Rockies.

860.1500 Crop Field Trials

The registrant must submit a revised Section F to adjust the proposed
tolerances to the levels of the recommended tolerances.  For caneberry,
the proposed tolerance of 4.0 ppm is acceptable.  However, the proposed
tolerance of 1.0 ppm for grapes (east of the Rocky Mountains) and 5.0
ppm for hops need to be adjusted based on submitted data and residue
calculations.  These tolerances should be resubmitted as 0.10 and 7.0
ppm respectively.  Also, the commodity definitions must be corrected as
recommended in Table 9.  

Pending the results of the forthcoming human-health risk assessment and
receipt of the revised labels for use on grapes (east of the Rocky
Mountains) and hops, and the revised Section F, ARIA recommends
establishing permanent tolerances for cymoxanil on grape at 0.10 ppm;
hop, dried cones at 7.0 ppm; and caneberry, subgroup 13A at 4.0 ppm.

A human health risk assessment will be prepared as a separate document.

Background

  SEQ CHAPTER \h \r 1 Cymoxanil is one of the technical active
ingredients included in the fungicide Tanos® DF, a dry flowable
formulation containing 25% ai famoxadone + 25% ai cymoxanil.  Cymoxanil
provides control of pathogen species of the order Peronosporales (e.g.
Phytophthora, Plasmopara and Peronospora) in grapes, potatoes, tomatoes,
hops, tobacco, cucurbits and caneberries.  Possible modes of action
include the inhibition of nucleic acid synthesis, mycelial respiration,
membrane permeability and reduction of sporulation.  The chemical
structure and nomenclature of cymoxanil are presented in Table 1.  The
physicochemical properties of cymoxanil are presented in Table 2.

DuPont™ Tanos® Fungicide; EPA Reg. No. 352-604) contains 25%
cymoxanil and 25% famoxadone



Table 2.	  Physicochemical Properties.

Parameter	Value	Reference

Melting range	  SEQ CHAPTER \h \r 1 159-160°C	MRID 45620301 (L.
Croteau, Pest Management Regulatory Agency (PMRA))

pH	  SEQ CHAPTER \h \r 1 4.1

	Density	  SEQ CHAPTER \h \r 1 1.32 g/cm3

	Water solubility	  SEQ CHAPTER \h \r 1 0.9 g/Lin water, pH 5

	Solvent solubility	  SEQ CHAPTER \h \r 1 62.4 g/L in acetone

	Vapor pressure	  SEQ CHAPTER \h \r 1 1.5 x 10-4 Pa at pH 5

	Dissociation constant, pKa	  SEQ CHAPTER \h \r 1 9.7 ± 0.2

	Octanol/water partition coefficient (log Kow)	  SEQ CHAPTER \h \r 1 3.9
at pH 5, 4.7 at pH 7

	UV/visible absorption spectrum	Not reported

	

860.1200  Directions for Use

The petitioner submitted an undated draft specimen label for a 50% dry
flowable (DF) multiple active ingredient (MAI) formulation (Tanos®
fungicide; EPA Reg. No. 352-604) containing 25% cymoxanil and 25%
famoxadone.  In addition, the petitioner included the current accepted
registered label for the same formulation (dated 24/JUN/2005) along with
the proposed use pattern for grapes (east of the Rocky Mountains), hops
and caneberries.  The product proposed for amended use is presented in
Table 3.  A summary of the proposed uses on grapes (east of the Rocky
Mountains), hops and caneberries is presented in Table 4.  ARIA notes
that the use pattern from the undated draft label differs from the use
pattern proposed in Section B for the commodities, hops and grapes.

Table 3.  Summary of Proposed End-Use Products.

Trade Name	Reg. No.	ai (% of formulation)	Formulation Type	Target Crops
Target Pests	Label Date

Tanos® DF Fungicide	352-604	25% cymoxanil

25% famoxadone	Dry flowable (DF)	Grapes (east of the Rocky Mountains)

Hops

Caneberry	Downy mildew,

Late blight, Anthracnose, Cane blight, Botrytis, Leaf Spots, Septoria
leafspot, spur blight	undated draft label



Table 4.  Summary of Directions for Use of Cymoxanil.

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

Grapes (East of the Rocky Mountains)

Foliar spray

Ground, aerial, or chemigation	Section B	0.25	Not specified (NS)	2.5	30





Tanos® DF Fungicide

 Undated specimen label;

[352-604]	0.094-0.125	3 per crop cycle	0.375 per crop cycle

1.125 per year	30	Applications may be made in a minimum of 20 gal/A
using ground equipment or 5 gal/A using aerial equipment with a 5- to
7-day retreatment interval.

Hops

Foliar spray

Ground, aerial, or chemigation	Section B	0.125-0.25	NS	1.5	7



Tanos® DF Fungicide 

Undated specimen label;

[352-604]	0.125-0.156	3 per crop cycle	0.469 per crop cycle

1.125 per year	7	Applications may be made in a minimum of 20 gal/A using
ground equipment or 10 gal/A using aerial equipment with a 5- to 7-day
retreatment interval.

Caneberry

Foliar spray

Ground, aerial, or chemigation	Sectioin B	0.1875	NS	1.125	0



Tanos® DF Fungicide 

Undated specimen label;

[352-604]	0.177-0.213	6	1.125 per cropping season/year	0	Applications
may be made in a minimum of 20 gal/A using ground equipment or 5 gal/A
using aerial equipment with a 5- to 7-day retreatment interval.

* The ai refers to cymoxanil, only.

  SEQ CHAPTER \h \r 1 The following general use directions are also
specified for the 50% DF formulation containing 25% cymoxanil and 25%
famoxadone.    SEQ CHAPTER \h \r 1 Famoxadone, one of the active
ingredients, is a Group 11 (Qol-containing) fungicide, which also
includes all strobilurins and fenamidone.  The following recommendations
were made regarding resistance management.  Do not make more than one
application of Tanos® before alternating with a fungicide that has a
different mode of action, such as maneb, copper, captan, fosetyl-Al, or
dimethomorph.  Do not make more than three applications of Tanos® or
other Group 11 fungicides (all strobilurins or fenamidone) per cropping
cycle.  Do not alternate or tank mix with fungicides to which resistance
has developed.  An REI of 12 hours is proposed.

The following rotational crop restrictions are specified on the undated
draft specimen label.  Crops listed on the label [cucurbits, grapes
(east of the Rocky Mountains), head lettuce, hops, peppers, potatoes,
tomatoes, and canberries] may be planted back at any time and all other
crops may be planted back following a minimum plantback interval of 30
days.

Conclusions.  The directions for use shown on the draft label for use on
caneberry are consistent with the use directions utilized in the
submitted field trial studies.  No label amendments for Tanos® DF (EPA
Reg. No. 352-604) are required for this commodity.  The proposed uses of
  SEQ CHAPTER \h \r 1 Tanos® DF on hops and grapes grown east of the
Rockies are inadequately delineated because of discrepancies regarding
the maximum single and seasonal rates listed in Section B and the
submitted specimen label.  For hops, label revision is required to allow
consistency of use pattern with the field trial data; the label must be
revised to specify a maximum single foliar application rate of 0.25 lb
ai/A with a 6- to 8-day RTI and a maximum seasonal rate of 1.5 lb ai/A. 
For grapes, the label must be revised to comply with the HED ChemSAC’s
determination that   SEQ CHAPTER \h \r 1 residue data generated in
Europe (France, Germany, Greece, and Spain) for use of cymoxanil plus
famoxadone on grapes could be translated to support use on grapes grown
east of the Rockies provided the use patterns are identical or the use
pattern is more restrictive (i.e., lower application rates and longer
PHI).  The proposed use on grapes east of the Rockies should be revised
to specify a maximum single application rate of 0.107-0.125 lb ai/A, a
maximum of 9 applications per season (for an implied seasonal rate of
1.125 lb ai/A) with a 10-day retreatment interval, and a PHI of 30 days.

860.1300 Nature of the Residue - Plants

Plant metabolism studies with cymoxanil have been conducted on grape,
potato, tomato, and lettuce.  The results from each study are summarized
below.

Grape

MRID   SEQ CHAPTER \h \r 1 43616532 (DP Num: 218035 and 219844,
25/APR/1996, G. Kramer)

  SEQ CHAPTER \h \r 1 Labeled cymoxanil was applied to grapes in outdoor
plots at a rate of 210 g ai/ha.  A total of eight applications were
performed at biweekly intervals.  Grape samples were taken 0, 1, 4, 10,
and 18 days after the final application.  The TRR ranged from 2.1 to 2.5
ppm.  The organic soluble fraction was found to contain cymoxanil per se
(11% of the TRR at day 0 and 2% at day 18) and the metabolite IN-U3204
(at a maximum level of 0.01 ppm or 0.5% of the TRR).  The aqueous
soluble fraction in the 10-day sample was comprised of natural
components such as glycine (23% of the TRR), acetic acid (9% of the TRR)
and sugars (15% of the TRR).

Potato

MRID   SEQ CHAPTER \h \r 1 43616532 (DP Num: 218035 and 219844,
25/APR/1996, G. Kramer)

  SEQ CHAPTER \h \r 1 Labeled cymoxanil was applied to potatoes in
outdoor plots at a rate of 210 g ai/ha.  A total of four applications
were performed at weekly intervals.  Potato samples were taken 10 days
after the final application and the TRR was 2.4 ppm.  The
aqueous-soluble fraction was comprised of natural components such as
glycine (58% of the TRR), other amino acids (11% of the TRR) and sugars
(14% of the TRR).

Tomato

44439601.der.wpd (DP Num: 261144, 21/NOV/2002, S. Levy)

Radiolabeled cymoxanil was applied three times (0.56 lb ai/A) at 15-19
day interval to tomato plants for a total of 1.68 lb ai/A/season (1.5x
the recommended label rate).  Control tomato plants were grown under the
same conditions as the treated plants in a field plot.

Mature tomato fruits were harvested three days after the last
application.  The TRRs were 1.1 ppm in mature tomato fruits (PHI 3
days).  About 11.2% of the TRRs were rinsed off the fruit with an
aqueous buffer (pH 5.0) and 81.7 % of the TRRs were extractable in water
(including protease digestion released radioactivity).  About 7.1% of
the TRRs were unextractable.  Cymoxanil was detected at approximately
0.01 ppm in the fruit.  No other closely related metabolites were found
at greater than 0.05 ppm.  The major component identified in the
extractable radioactivity after acid hydrolysis was glycine (65.2% of
the TRR, 0.72 ppm).  A small percentage of radioactivity was also found
in sugars (glucose and fructose).

Lettuce

  SEQ CHAPTER \h \r 1 44944605.der.wpd (DP Num: 261144, 21/NOV/2002, S.
Levy) 

Radiolabeled cymoxanil was applied four times (0.75 lb ai/A) at 15-28
day interval to lettuce plants for a total of 2.99 lb ai/A/season (2.6x
the recommended label rate).  Control lettuce plants were grown under
the same conditions as the treated plants.

Mature leaf lettuce was harvested three days after the last application.
 The TRR was 10.78 ppm in mature lettuce.  About 7.5% of the TRRs (0.81
ppm) were rinsed off the lettuce and 64.6% of the TRRs (6.96 ppm) were
extractable in an aqueous buffer.  About 27.9% of the TRR (3.01 ppm) was
bound.  Cymoxanil was detected only in the surface wash of the lettuce
(2.1% of the TRR; 0.23 ppm).  The major component identified in the
extractable radioactivity after acid hydrolysis was glycine (30.6% of
the TRR; 3.30 ppm).  Glucose from both the surface wash and extracted
foliage totaled 21.1% of the TRR (2.28 ppm).  The surface wash and
extract also contained several other polar metabolites, including
IN-KP533 (2.8% TRR) and IN-KQ960 (7.4% TRR).  The bound radioactivity in
the pellet was further characterized via acid hydrolysis, cellulase and
protease enzymatic digestion.  Acid hydrolysis released 15.4% of the TRR
(1.66 ppm), while cellulase and protease enzymatic digestion released
3.4% (0.36 ppm) and 12.7% (1.37 ppm) of the TRR, respectively.  The
major components were sugars with several other polar components.  A
small amount of glycine was identified in the acid hydrolysis and
protease digestion extracts following derivatization and HPLC analysis.

Conclusions:    SEQ CHAPTER \h \r 1 The nature of the residue in grape,
lettuce, potato, and tomato is adequately understood.  In grapes,
potatoes, and tomatoes, cymoxanil was metabolized primarily into
[14C]glycine, and further incorporated into the sugars fructose and
glucose (DP Num: 241752, 246386, 247216, 247217, and 247210, G.
Kramer/J. Rowell, 19/AUG/1998 and DP Num: 233933, G. Kramer,
19/NOV/1997).  An ad hoc HED MARC met on 1/21/98 to discuss the
toxicological significance of potential metabolites.  It was decided
that only the parent is of regulatory concern (DP Num: 242321, G.
Kramer/S. Chun, 26/JAN/1998).  HED, thus, concluded that cymoxanil per
se is the only residue of concern for tomatoes, potatoes, grapes,
livestock, rotational crops, and drinking water.  Subsequently, HED
translated these data for a previous Section 18 emergency exemption
action for hops.  Based on the submitted data and crop similarities, the
tolerance expression for cymoxanil on caneberry is cymoxanil per se.  

  SEQ CHAPTER \h \r 1 Since the previous MARC meeting, the petitioner
submitted a lettuce metabolism study.    SEQ CHAPTER \h \r 1 Metabolites
IN-KQ960 and IN-KP533 were identified in the lettuce metabolism study
but these metabolites were not detected in the tomato, grape, or potato
metabolism studies.  These results were presented to the HED MARC on
07/AUG/2001 to assess the toxicological significance of these
metabolites and to determine which additional residues, if any, to
regulate (DP Num: 276543, S. Levy/G. Kramer, 01/AUG/2001).  The MARC
determined that the nature of the residue is understood in leafy
vegetables (DP Num: 276796, S. Levy, et.al., 30/AUG/2001).  For the
plant metabolism studies conducted to this point, the detection of
metabolites IN-KQ960 and IN-KP533 is unique in lettuce.  The MARC
concluded that for the tolerance expression, the residue of concern
in/on hops is cymoxanil per se.  For risk assessment purposes, the
metabolite IN-KQ960 must be included, along with the parent, based on
the ratio (3.5:1) of IN-KQ960 to the parent in the lettuce 14C
metabolism study.  

860.1300 Nature of the Residue - Livestock

There are no livestock feedstuffs associated with the proposed use on
grapes, hops, and caneberries.  Therefore, data requirements for
livestock metabolism are not relevant to this tolerance petition.

860.1340 Residue Analytical Methods

Enforcement methods  

An adequate HPLC/UV method is available for the enforcement of proposed
grape tolerance.  Method AMR 3060-90 (MRIDs   SEQ CHAPTER \h \r 1
43616541 and 43640504, DP Num: 218035 and 219844, G. Kramer,
25/APR/0996) was submitted in support of the previous tolerance petition
(PP#5E04504) for imported grapes and tomatoes.  Using this method,
residues in/on crop s  SEQ CHAPTER \h \r 1 amples are extracted by
homogenization in ethyl acetate.  Solids are removed by centrifugation,
and the extract is concentrated and exchanged into acetone.  After
clean-up by SAX and silica column chromatography, the hexane/ethyl
acetate eluate is exchanged into methanol.  Cymoxanil is then analyzed
using HPLC on a CN column with UV detection (254 nm).  Column switching
with a C-18 column is used if additional clean-up is required.  The LOQ
was reported to be 0.05 ppm.  Method AMR 3060-90 was successfully
validated by an independent laboratory and had been forwarded to ACL for
a PMV (DP Num: 224541, G. Kramer, 01/APR/1996).  The PMV was successful;
however, ACB recommended (DP Num: 228837, G. Kramer, 05/AUG/1996) two
revisions to the method (removal of directions to subtract the response
of control samples and modification of the HPLC column specifications to
indicate that a 25-cm column should be used instead of a 15-cm column). 
In response, the petitioner submitted Method AMR 3060-90 Revision No. 2
(MRID 44579103), and Agency review (DP Num: 241752, G. Kramer,
19/AUG/1998) of the re-written method concluded that it is adequate for
enforcement method.

The submitted method (HPLC/MS) is an adequate enforcement method for
hops.  In a previous hop petition (PP#1E06224), the petitioner submitted
a method (MRID 45226701) derived from DuPont’s "Method Validation for
the Quantitation of Cymoxanil Residue in Fresh and Dried Hops." 
Preliminary HED review (DP Num: 276291, S. Levy/G. Kramer, 21/NOV/2002)
of the method shows that it determines residues of cymoxanil per se, and
acceptable recoveries were obtained during a method verification trial. 
However, the review noted that the submitted hops method differed from
the available grape/tomato method (and an existing potato method). 
After personal communication with ACL (S. Levy to F. Griffith,
25/JUL/2001), HED requested that ACL review the proposed enforcement
method and decide whether an ILV of this method should be conducted
prior to initiation of the PMV.  Since this request, a new enforcement
method had been submitted using HPLC/MS.  The only major change between
the validated method and the newly submitted method is the use of MS
detection versus UV detection.  This deficiency is resolved, and the
requirements for analytical enforcement methodology for hops are
fulfilled.  

Data-collection methods

Samples of grapes addressed in this document were analyzed for residues
of cymoxanil using a GC/NPD method [referenced as a multi-residue
enforcement method (DFG S 19 Modified) for the determination of
cymoxanil in dry, high water, and oil crops].  Adequate concurrent
method recovery data have been submitted for this method.  The validated
method LOQ is 0.04 ppm, and the LOD is not reported.

Samples of dried hop cones addressed in this document were analyzed for
residues of cymoxanil and famoxadone using the enforcement method (AMR
3705-95, Revision No. 2) with modifications.  The petitioner stated that
a major change to the method is that both famoxadone and cymoxanil are
analyzed by LC/MS.  In the original method, famoxadone was analyzed by
GC/NPD and cymoxanil by LC/UV.  Adequate method validation and
concurrent method recovery data have been submitted for this method. 
The lowest limit for method validation (LLMV) is 0.05 ppm for cymoxanil,
and the calculated LOQ and LOD are 0.041 and 0.014 ppm, respectively,
for residues of cymoxanil.

860.1360 Multiresidue Methods

  SEQ CHAPTER \h \r 1 The petitioner has previously submitted data
pertaining to the FDA Multiresidue Methods testing of cymoxanil in
conjunction with the grape and tomato tolerance petition (G.F. Kramer,
26/MAR/1996).  The data indicate that cymoxanil was recovered using
Protocol D which can, therefore, be used as a confirmatory method (DP
Num: 218035 and 219844, G. Kramer, 25/APR/1996).  The report was
forwarded to FDA.

860.1380 Storage Stability

Samples of grapes, hops, and caneberries collected from the field and
processing studies, were stored frozen prior to residue analysis.  The
storage intervals and conditions of samples are presented in Table 5
below.

Table 5.   Storage Conditions and Intervals of Samples from Field Trial
and Processing Studies.

Matrix 

[MRID]	Storage Temperature

(°C)	Actual Storage Duration	Interval of Demonstrated Storage Stability

Grape, fruit

[46670202]	-18	48-78 days

(1.6-2.6 months)	Residues of cymoxanil are stable at -20 ºC for up to
18 months in/on grape, grape juice, and dry pomace. 1

Grape, fruit and processed commodities

≤8 months (RAC)

≤6 months (processed fractions)

	Hops, dried cones

[46670201]	-20	195-206 days

(6.4-6.8 months)	Storage stability data (MRID 46670201) submitted in
conjunction with the hops field trial study indicate that residues of
cymoxanil are stable for up to 258 days (8.5 months) in/on dried hops.

Caneberries

 [46959001]	< -21	154 days	Submitted storage stability studies show that
cymoxanil residues are stable on caneberry for up to 216-216 days with
recoveries ranging from 94 – 98%.

1  Data (MRID 43616538) submitted in a previous petition review; refer
to PP#0F06072; DP Num: 261144,    

   21/NOV/2002, S. Levy.

Conclusions.  There are adequate storage stability data to support the
integrity of samples collected from field and processing studies. 
Residues of cymoxanil are stable under frozen storage conditions for up
to 18 months in/on grapes and it processed fractions (juice and dry
pomace), 8.5 months in/on dried hops and ~5months on caneberries.  There
are no storage stability issues or corrections that may need to be
applied to the various residue studies.

860.1400 Water, Fish, and Irrigated Crops

There are no proposed/registered uses that are relevant to this
guideline.

860.1460 Food Handling

There are no proposed/registered uses that are relevant to this
guideline.

860.1480 Meat, Milk, Poultry, and Eggs

There are no livestock feedstuffs associated with the proposed use on
grapes, hops and caneberries.  Therefore, data requirements pertaining
to meat, milk, poultry, and eggs are not relevant to this tolerance
petition.

860.1500 Crop Field Trials

IR-4 has submitted magnitude of the residue studies for grape, hop,
dried cones, and caneberry, Subgroup 13A in support of proposed
tolerances discussed in this document.  These studies have been
reviewed, and the Executive Summaries of field trial DERs are reproduced
below followed by a crop conclusion.

Grape

46670202.der.doc, D.Rate, 06/NOV/2006

MRID 43616533 (DP Num: 218035 and 219844, G. Kramer, 25/APR/1996)

Table 6.   Summary of Residue Data from European Grape Field Trials with
Cymoxanil Submitted to

                Support Use of Tanos® DF on Grapes Grown East of the
Rocky Mountains.  

Crop matrix	Total Applic. Rate

(lb ai/A)

[kg ai/ha]	PHI (days)	Residue Levels (ppm) 1



	n	Min.	Max.	HAFT 2	Median	Mean	Std. Dev.

Grape (proposed use = 0.375 lb ai/A/ crop cycle or 1.125 lb ai/A/year
total application rate, 30-day PHI)

Wine grape, fruit	1.20-1.46

[1.34-1.64]	28	12	<0.04	<0.04	<0.04	0.02	0.02	0.0

1  The method LOQs were <0.04 and <0.05 ppm.  The median, mean, and
standard deviation were calculated using half the LOQ (<0.02 and <0.025
ppm) for all residues reported as <0.04 and <0.05 ppm.

2  HAFT = Highest average field trial result.

The Interregional Research Project No. 4 (IR-4) has submitted field
trial data depicting the magnitude of the residue of cymoxanil in/on
wine grapes.  A total of 12 field trials were conducted in Europe on
wine grapes during the 1999 growing season in Greece (2 trials), Italy
(2 trials), southern France (4 trials), northern France (2 trials), and
Germany (2 trials).  However, only samples from four trials conducted in
northern France (2 trials) and Germany (2 trials) were analyzed for
residues of cymoxanil.  At each test location, a total of 10 foliar
spray applications of a water-dispersible granular (WG) formulation
(containing 30% cymoxanil and 22.5% famoxadone) were applied to wine
grapes during the growing season at progressive vine growth stages.  The
first seven applications were made at 0.079-0.142 lb
cymoxanil/A/application followed by three applications made at
0.162-0.173 lb cymoxanil/A/application, for a total rate of 1.197-1.462
lb cymoxanil/A.  Applications were made with a 6- to 8-day retreatment
interval (RTI), using ground equipment (knapsack or portable sprayer) in
~88-171 gal/A spray volumes; no adjuvant was added to the spray mixture.

Samples of mature wine grapes were harvested 28 days after the last
application (preharvest interval (PHI)).  At one location, additional
immature grape samples were collected 0, 1, 7, and 14 PHI to generate
residue decline data.    SEQ CHAPTER \h \r 1 We note that the WG
formulation used in the grape field trials also contained another active
ingredient (famoxadone); data for the famoxadone active ingredient are
reviewed in conjunction with a separate petition (refer to PP#5E7001; DP
Num: 323682); only data pertaining to cymoxanil are presented herein.

The maximum storage interval of crop samples from harvest to analysis
was 78 days (2.6 months) for grapes.  The results of a storage stability
study (MRID 43616538) were submitted in conjunction with a previous
petition (PP#0F06072; DP Num: 261144, 21/NOV/2002, S. Levy) which
indicate that residues of cymoxanil are stable under frozen storage
conditions in/on fortified samples of grapes for up to 18 months.  These
data are adequate to support the storage intervals of samples from the
grape field trials.

  SEQ CHAPTER \h \r 1 Samples of grapes were analyzed for residues of
cymoxanil using a gas chromatography (GC)/nitrogen/phosphorus detector
(NPD) method, referenced as a multi-residue enforcement method (DFG S 19
Modified) for the determination of cymoxanil in dry, high water, and oil
crops.  The validated limit of quantitation (LOQ) was 0.04 ppm, and the
limit of detection (LOD) was not reported.  This method is adequate for
data collection based on acceptable concurrent method recovery data.

The results from the grape field trials show that residues of cymoxanil
were below the method LOQ (<0.04 ppm) in/on wine grapes harvested 28
days after the last of ten foliar spray applications at 1.197-1.462 lb
cymoxanil/A.  Residue decline data show that cymoxanil decreases in wine
grapes with increasing PHIs.

Conclusions:  The residue data from the current field trial submission
indicate that residues of cymoxanil were below the LOQ of 0.04 ppm in/on
grapes harvested 28 days after the last of ten foliar spray applications
of Tanos® DF formulation at a total rate of 1.197-1.462 lb cymoxanil/A.
 The residue data that were submitted in support of the grape import
tolerance of 0.1 ppm (PP#5E04504 and PP#7F04814 (DP Num: 218035 and
219844, G. Kramer, 25/APR/1996; DP Num: 241752, 246386, 247216, 247217,
and 247210, G. Kramer, 8/19/98; and DP Num: 249398, G. Kramer,
18/SEP/1998) were conducted according to a use pattern reflecting 12
applications at 0.107 lb ai/A/application with a 10-day retreatment
interval for a total seasonal rate of 1.28  lb ai/A and a 14-day PHI. 
The available data are adequate to support the proposed use of Tanos®
DF on grapes grown East of the Rocky Mountains pending label revision to
conform with the HED’s ChemSAC (Directions for Use above.)
determination regarding  SEQ CHAPTER \h \r 1  data translation.

Hops

46670201.der.doc, D.Rate, 06/NOV/2006

Table 7.	 Summary of Residue Data from Hop Field Trials with Cymoxanil.

Crop matrix	Total Applic. Rate

(lb ai/A)	PHI (days)	Residue Levels (ppm)



	n	Min.	Max.	HAFT 1	Median	Mean	Std. Dev.

Hops (proposed use = 1.5 lb ai/A total application rate, 7-day PHI)

Hops, dried cones	1.50-1.53	7-8	6	1.13	4.07	3.76	1.36	2.09	1.32

1  HAFT = Highest average field trial result.

IR-4 has submitted field trial data depicting the magnitude of the
residue of cymoxanil in/on dried hops.  A total of three hop field
trials were conducted in the United States in Zones 11 (ID and WA) and
12 (OR) during the 2000 growing season.  At each test location, hop
plants received six directed foliar applications of the test
formulation, Tanos® DF, a dry flowable (DF) formulation containing 25%
ai famoxadone + 25% ai cymoxanil at ~0.25 lb cymoxanil/A/application
with a 6- to 8-day retreatment interval (RTI) for a total seasonal rate
of ~1.5 lb cymoxanil/A.  [Residue data for the famoxadone ai are
reviewed in conjunction with a separate petition (refer to PP#5E7001; DP
Num: 323682); only data pertaining to cymoxanil are presented herein.]  
  SEQ CHAPTER \h \r 1 No adjuvant was included in the spray mixture. 
Samples of fresh hop cones were harvested 7-8 days after the last
application (preharvest interval (PHI)), and cones were dried for
approximately 3-20 hours after harvest.

The maximum storage interval of dried hop samples from harvest to
analysis was 205 days (6.8 months).  The storage interval is supported
by adequate storage stability data which were generated concurrently
with the field trials.    SEQ CHAPTER \h \r 1 These data indicate that
residues of cymoxanil are stable in/on fortified dried hop samples
stored frozen up to 258 days.

Samples of hops were analyzed for residues of cymoxanil following liquid
chromatography (LC)/mass spectroscopy (MS) procedures described in
DuPont Report No. AMR 3705-95, Revision No. 2, “Analytical Method for
the Determination of DPX-JE874 and Cymoxanil Residues in Various
Matrices.”  The method was validated prior to analysis of the field
test samples.  The lowest limit of method validation (LLMV) was 0.05
ppm.  The calculated LOQ and LOD were 0.041 and 0.014 ppm, respectively,
for residues of cymoxanil.  This method is adequate for data collection
based on acceptable method validation and concurrent method recovery
data.

The results from the hop field trials show that the maximum residues of
cymoxanil were 4.07 ppm in/on dried hop cones harvested 7-8 days after
the last of six directed foliar applications at ~0.25 lb
ai/A/application for a total application rate of ~1.50 lb cymoxanil
(ai)/A.

Conclusions.  The residue data from the current field trial submission
indicate that residues of cymoxanil ranged from 1.13 ppm to 4.07 ppm
in/on dried hops harvested 7-8 days after the last of six directed
foliar applications of Tanos® DF formulation at ~0.25 lb
ai/A/application for a total rate of ~1.50 lb ai/A.  The submitted data
are adequate pending label revision to reflect the parameters of field
trial data.  ARIA is recommending label revisions to specify a maximum
single foliar application rate of 0.25 lb ai/A with a 6-8 day RTI and a
maximum seasonal rate of 1.50 lb ai/A.  The hop data were entered into
the Agency’s tolerance spreadsheet (see Appendix I), and statistical
analysis of data show that a tolerance level of 7.0 ppm will be
appropriate for hops.

Caneberry (Crop Subgroup 13A)

46905901.der.doc, D.Rate, 06/NOV/2006

TABLE 8.	Summary of Residue Data from Crop Field Trials with Cymoxanil.

Commodity	Total 

Application Rate,

lb ai/A1

(kg ai/ha)	PHI (days)	Residue Levels (ppm)



	n	Min.	Max.	HAFT1	Median (STMdR)	Mean (STMR)	Std. Dev.

Caneberry (proposed use = 1.125 lb cymoxanil/A total application rate; 0
day PHI)

Caneberries	1.124-1.141 (1.260-1.279)	0	14	0.24	2.2	2.1	0.54	0.889	0.666

1  HAFT = Highest average field trial result.

IR-4 has submitted field trial data for cymoxanil on caneberry.  Four
supervised crop field trials were conducted in CA (two trials, U.S. EPA
Region 10), WA (U.S. EPA Region 12) and OR (U.S. EPA Region 12) during
the 2003 growing season.  In addition, three supervised crop field
trials were conducted in Canada, with one trial in British Columbia
(Canadian Region 12), one trial in Ontario (Canadian Region 5), and one
trial in Quebec (Canadian Region 5B).  Six foliar applications of
DPX-KP481 50WG (25% cymoxanil) were applied at a rate of 0.75 lb
product/A (0.1875 lb cymoxanil/A) at 6-8 day retreatment intervals
(RTIs) (4.5 lb product/A/season, 1.125 lb cymoxanil/A/season).  Samples
were collected on the day of the last application (0-day PHI).  No
adjuvants or additives were added to the spray mixture for any of the
above applications.  The number and locations of field trials are in
accordance with OPPTS Guideline 860.1500 (with some acceptable
deviations).  

The analytical procedure for quantifying residues of cymoxanil was the
Cornell Analytical Laboratory Method Residue Analysis of Cymoxanil on
Caneberry by HPCL/UV.  This method was adapted from a method developed
by Morse Laboratories and E.I. duPont Nemours and Company and entitled
Analytical Method for the Determination of DPX-JE874 and Cymoxanil
Residues in Various Matrices.  Caneberry samples were extracted in
separate steps with acetonitrile/water and hexane and purified via
several solid phase extraction steps.  After addition of a KH2PO4 buffer
solution (pH 2.9) to purified samples, quantitation was accomplished by
high performance liquid chromatography (HPLC)/ultra-violet (UV)
detection.  Samples of control caneberry were fortified at levels
ranging from 0.05 to 5.0 ppm.  The limit of quantitation (LOQ) and the
limit of detection (LOD) were calculated to be 0.024 ppm and 0.0072 ppm,
respectively for caneberry.  The percent recovery of cymoxanil from
caneberry ranged from 64 -120%.  The method is adequate for data
collection.

The results from these trials show that cymoxanil residues ranged from
0.24 ppm to 2.2 ppm on/in treated caneberry when the test substance was
applied at the proposed seasonal application rate of 1.125 lb
cymoxanil/A using a 0-day PHI.  Caneberry was stored frozen for a
maximum of 154 days at –21ºC.  Submitted storage stability studies
indicate that cymoxanil residues are stable on caneberry for up to 216
days.  A residue decline study was not conducted by the petitioner.

aneberry were ≤ 2.2 ppm when applied at the proposed use rate (1.125
lb ai/A/season) and harvested at the proposed PHI (0-days).  The studies
conducted were consistent with standard agricultural practices as per
proposed experimental designs and no anomalous weather events were
recorded.  The analytical method has been found suitable for data
collection and for enforcement purposes.

860.1520 Processed Food and Feed

MRID 43616534 (DP Num: 218035 and 219844, G. Kramer, 25/APR/1996)

MRID 44450301 (DP Num: 241752, 246386, 247216, 247217, 247210, G.
Kramer, 19/AUG/1998)

HED’s ChemSAC (memo dated 19/APR/2004) concluded that European grape
data could be used to support the use in the eastern U.S.  They also
pointed out that a processing study was required to determine whether
cymoxanil residues concentrated in juice.  Data were not required for
raisins for a use limited to east of the Rocky Mountains.

The petitioner previously submitted European grape processing studies
(MRID 43616534) in conjunction with PP#5E04504.  These data were
reviewed by the Agency (DP Num: 218035 and 219844, G. Kramer,
25/APR/1996 and DP Num: 241752, 246386, 247216, 247217, 247210, G.
Kramer, 19/AUG/1998) where it was reported that concentration of
cymoxanil residues was observed only in juice (>1.4x) at one site.  The
highest average field trial (HAFT) residue of cymoxanil in/on grapes
treated according to the maximum use patterns is 0.07 ppm.  When the
processing factor for juice (>1.4x) is multiplied by the HAFT, the
maximum expected residue of cymoxanil in juice is 0.098 ppm.

Conclusions.  The field trials that supplied the grapes for processing
were conducted at 5x the field application rate.  Processing   SEQ
CHAPTER \h \r 1 followed typical commercial practices for grapes and the
residue data are supported by the analytical methods and storage
stability studies.  This study indicates that residues of cymoxanil per
se may concentrate (>1.4x) in grape juice processed from grapes bearing
nondetectable cymoxanil residues.  The HAFT residue of cymoxanil in/on
grapes treated according to the proposed maximum use patterns is 0.07
ppm.  When the processing factor for juice (>1.4x) is multiplied by the
HAFT, the product is below the reassessed tolerance of 0.1 ppm for the
RAC (grape).  Provided the labels are amended to reflect the maximum
seasonal rate (1.5 lb cymoxanil/A) use in the field trials, a cymoxanil
tolerance for grape juice is not needed because the expected residue in
this processed commodity will be covered by the RAC tolerance.

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

Analytical standards for cymoxanil are currently available in the
National Pesticide Standards Repository.  Analytical reference standards
of cymoxanil must be supplied and supplies replenished as requested by
the Repository.  The reference standards should be sent to the
Analytical Chemistry Lab, which is located at Fort Meade, to the
attention of either Theresa Cole or Frederic Siegelman at the following
address:

	USEPA

	National Pesticide Standards Repository/Analytical Chemistry Branch/OPP

	701 Mapes Road

	Fort George G. Meade, MD  20755-5350

(Note that the mail will be returned if the extended zip code is not
used.)

860.1850 Confined Accumulation in Rotational Crops

860.1900 Field Accumulation in Rotational Crops

Grapes, hops and caneberries   SEQ CHAPTER \h \r 1 are crops which are
typically not rotated; therefore, the proposed uses are not relevant to
these topics.

860.1550 Proposed Tolerances

General tolerances are currently listed in 40 CFR (180.503(a) for
residues of the fungicide cymoxanil
(2-cyano-N-[(ethylamino)carbonyl]-2-(methoxyimino)acetamide).  The MARC
had determined that the residue of concern for tolerance enforcement is
cymoxanil per se.  The proposed tolerance expression is consistent with
40 CFR §180.503.  For risk assessment purposes, the metabolite IN-KQ960
must be included, along with the parent, based on the ratio of IN-KQ960
to the parent (3.5:1) in the lettuce 14C metabolism study, in lettuce
and hops.

The aggregate of residue data for grapes indicate that the appropriate
RAC tolerance is 0.10 ppm to support the proposed use of Tanos® DF on
grapes grown east of the Rocky Mountains and the entry to the United
States of Curzate®-treated grapes imported from Europe.  The reassessed
tolerance on grapes should be transferred under section (c) of 40 CFR
§180.503 as a tolerance with regional registration and should be
footnoted to indicate that it is also an import tolerance.  The
remaining tolerances would be classified under section (a) as general
tolerances.  Sections (b) and (d) will be reserved for Section 18
emergency exemptions and indirect or inadvertent residues, respectively.

The recommended tolerance of 7.0 ppm for hop, dried cones is contingent
upon label revisions and was derived with the aid of a spreadsheet.  The
recommended tolerance of 4.0 ppm for caneberry (Crop Subgroup 13A) was
derived with the aid of the MRL calculator/spreadsheet.  The tolerance
spreadsheet was not used for grape because previously submitted and
reviewed European residue data were used to support use in the Eastern
U.S.

A summary of tolerance reassessment is presented in Table 9.

Table 9. 	Tolerance Summary for Cymoxanil

Commodity	Established Tolerance

[40 CFR §180.503(a)] (ppm)	Proposed Tolerance (ppm)	Recommended
Tolerance (ppm)	Comments; Correct Commodity Definition

Hop, dried cones	1.0	5.0	7.0	Correct commodity definition

The recommended tolerance is contingent on label revisions to specify a
maximum single foliar application rate of 0.25 lb ai/A with a 6-8 day
RTI and a maximum seasonal rate of 1.5 lb ai/A.  The recommended
tolerance is based on field trial residues and calculated by the MRL
calculator.

Grape	0.11	1.0	0.10	Label revisions are required to comply with the
HED’s ChemSAC determination (see ChemSAC memo dated 04/19/04)
regarding data translation.  Based on the available European field trial
data for wine grapes, the following label revisions are required to
allow use of Tanos® DF on grapes grown East of the Rocky Mountains:  a
maximum single application rate of 0.107 lb ai/A, a maximum of 10
applications per season (for an implied seasonal rate of 1.07 lb ai/A)
with a 7-12 day retreatment interval, and a PHI of 14 days.

Caneberry, subgroup 13A

	---	4.0	4.0	Correct commodity definitions.

The recommended tolerance is based on field trial residues and
calculated by the MRL calculator. 

1  The established tolerance for grape does not have U.S. registration.

References

DP Num:	228837

Subject:	PP#5E04504.  Cymoxanil in/on Imported Tomatoes and Grapes. 
Results of Petition Method Validation.

From:		G. Kramer

To:		C. Eiden/D. McCall

Dated:		05/AUG/1996

MRID(s):	53616541 and 43640504

DP Num:	218035 and 219844

Subject:	PP#5E04504.  Cymoxanil in/on Imported Tomatoes and Grapes. 
Evaluation of Residue Data and Analytical Methods.  Chemical 129106.

From:		G. Kramer

To:		C. Welch/D. McCall

Dated:		25/APR/1996

MRID(s):	43616501-43616511, 43616532-43616541, 43640504, 43640505, and
43773901

DP Num:	233933

Subject:	PP#7F04805.  Cymoxanil (Curzate® M-8) in/on Potatoes. 
Evaluation of Residue Data and Analytical Methods.  Chemical 129106.

From:		G. Kramer

To:		M. Waller/L. Kutney

Dated:		19/JAN/1997

MRID(s):	44180703, 44180704, 44180748, 44180753, 44180755-44180759;
44200701 and 44200703

DP Num:	242321

Subject:	Cymoxanil (Curzate® M-8) in/on Potatoes.  PP#7F04805.  The
Pre-Metabolism Assessment Review Committee Meeting Held on 1/21/98. 
Residues of Concern in Animal Commodities.

From:		G. Kramer/S. Chun

To:		Members of the HED Metabolism Assessment Review Committee

Dated:		26/JAN/1998

MRID(s):	None

DP Num:	241752, 246386, 247216, 247217, and 247210

Subject:	PP#7F04814 (formerly PP#5E04504).  Cymoxanil in/on Imported
Tomatoes and Grapes.  Amendment of 12/4/97.  Revised Section B, Revised
Method and Additional Metabolism and Residue Data.  Chemical 129106.

From:		G. Kramer/J. Rowell

To:		L. Kutney/M. Waller

Dated:		19/AUG/1998

MRID(s):	44169001-44169007

DP Num:	249398

Subject:	PP#7F04814 (formerly PP#5E04504).  Cymoxanil in/on Imported
Tomatoes and Grapes.  Amendment of 8/27/98.  Revised Section B. 
Chemical 129106.

From:		G. Kramer

To:		L. Kutney/M. Waller

Dated:		18/SEP/1998

MRID(s):	None

DP Num:	276543

Subject:	PP#1E06224.  Cymoxanil (Curzate® 60 DF) in/on Hops.  Issues to
be Presented to the HED Metabolism Assessment Review Committee (MARC) on
07-AUG-2001.  PC Code: 129106

From:		S. Levy/G. Kramer

To:		Y. Donovan

Dated:		01/AUG/2001

MRID(s):	None

DP Num:	276643

Subject:	PP#1E06224.  Cymoxanil (Curzate® 60 DF) in/on Hops.  Request
for Petition Method Validation (PMV).  PC Code: 129106

From:		S. Levy

To:		F. Griffith

Dated:		08/AUG/2001

MRID(s):	None

DP Num:	276796

Subject:	PP#1E06224.  Cymoxanil:  Results of Health Effects Division
(HED) Metabolism Assessment Review Committee (MARC) on 8/8/01.  PC Code:
129106

From:		S. Levy/G. Kramer/D. Nixon

To:		Y. Donovan

Dated:		30/AUG/2001

MRID(s):	None

DP Num:	276291

Subject:	PP#1E06224.  Cymoxanil (Curzate® 60 DF) in/on Hops. 
Evaluation of Residue Data and Analytical Methods.  PC Code:  129106.

From:		S. Levy/G. Kramer

To:		R. Forrest/S. Brothers

Dated:		21/NOV/2002

MRID(s):	44944605, 45226700, and 45226701

DP Num:	261144

Subject:	PP#0F06072.  Cymoxanil in/on Cucurbits, Fruiting Vegetables,
and Head Lettuce.  Evaluation of Residue Data and Analytical Methods.

From:		S. Levy

To:		M. Waller/S. Gardner

Dated:		21/NOV/2002

MRID(s):	43616538, 44180756, 44439601, 44579102, 449444605,
44946427-44946430

DP Num:	None

Subject:	Minutes of the 4/7/04 ChemSAC Meeting

From:		HED’s Chemistry Science Advisory Council

To:		HED’s Chemistry Interest Group

Dated:		19/APR/2004

MRID(s):	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: 
[2-cyano-N-[(ethylamino)carbonyl]-2-(methoxyimino)acetamide]	Common
Name:

Cymoxanil	X Proposed tolerance

X Reevaluated tolerance

 Other	Date: 10/26/06

Codex Status (Maximum Residue Limits)	U. S. Tolerances

X  No Codex proposal step 6 or above

 No Codex proposal step 6 or above for the crops requested	Petition
Number:  PP#6E7100

DP Num:  333252

  No Limits

XNo Limits for the crops requested	    No Limits

X   No Limits for the crops requested

Residue definition  2-cyano-N-[(ethylamino)

carbonyl]-2-(methoxyimino) acetamide

	Residue definition:  cymoxanil

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





















S.Funk, 10/30/2006.



Appendix I.  Tolerance Assessment Calculations.

The dataset used to establish a tolerance for cymoxanil on hop consisted
of field trial data representing application rates of 1.50-1.53 lb ai/A
(6 applications at 0.24-0.26 lb ai/A/application) with a 7- to 8-day
PHI.  As specified by the Guidance for Setting Pesticide Tolerances
Based on Field Trial Data SOP, the field trial application rates and
PHIs are within 25% of the maximum label application rate and minimum
label PHI, respectively.  The residues values used to calculate the
tolerance are provided in Table I-1.

All 6 field trial sample results were above the LOQ.  Since there were
no values reported below the LOQ, maximum likelihood estimation (MLE)
procedures were not needed to impute censored values. 

The cymoxanil-hop dataset was entered into the tolerance spreadsheet. 
Visual inspection of the lognormal probability plot (Figure I-1)
provided in the spreadsheet indicates that the dataset is reasonably
lognormal.  The result from the approximate Shapiro-Francia test
statistic (Figure I-2) confirmed that the assumption of lognormality
should not be rejected.

Since the field trial data for cymoxanil on hop represent a small
dataset (i.e., less than 15 samples) and are reasonably lognormal, the
upper bound estimate of the 95th percentile based on the median residue
value was compared to the minimum of the 95% upper confidence limit
(UCL) on the 95th percentile and the point estimate of the 99th
percentile, and the minimum value was selected as the tolerance value. 
Using the rounding procedure as outlined in the Guidance for Setting
Pesticide Tolerances Based on Field Trial Data SOP, 7.0 ppm is the
recommended tolerance level for cymoxanil on hop.

Table I-1.	Residue data used to calculate tolerance for cymoxanil on
hop.

Regulator:	  EPA

Chemical:	  Cymoxanil

Crop:	  Hop

PHI:	  7-8 Days

App. Rate:	  1.50-1.53 lb ai/A

Submitter:	  IR-4

MRID Citation:	  MRID 46670201

	Residues of Cymoxanil (ppm)

	1.13

	1.52

	1.14

	1.20

	3.45

	4.07



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

Figure I- 2.   Tolerance spreadsheet summary of cymoxanil field trial
data for hop.

	

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ticide Tolerances Based on Field Trial Data SOP, the field trial
application rates and PHIs are within 25% of the maximum label
application rate and minimum label PHI, respectively.  The residues
values used to calculate the tolerance are provided in Table I-1.

All 6 field trial sample results were above the LOQ.  Since there were
no values reported below the LOQ, maximum likelihood estimation (MLE)
procedures were not needed to impute censored values. 

The cymoxanil-caneberry dataset was entered into the tolerance
spreadsheet.  Visual inspection of the lognormal probability plot
(Figure I-1) provided in the spreadsheet indicates that the dataset is
reasonably lognormal.  The result from the approximate Shapiro-Francia
test statistic (Figure I-2) confirmed that the assumption of
lognormality should not be rejected.

Since the field trial data for cymoxanil on caneberry represent a small
dataset (i.e., less than 15 samples) and are reasonably lognormal, the
upper bound estimate of the 95th percentile based on the median residue
value was compared to the minimum of the 95% upper confidence limit
(UCL) on the 95th percentile and the point estimate of the 99th
percentile, and the minimum value was selected as the tolerance value. 
Using the rounding procedure as outlined in the Guidance for Setting
Pesticide Tolerances Based on Field Trial Data SOP, 4.0 ppm is the
recommended tolerance level for cymoxanil on caneberry.

Table I-2.	Residue data used to calculate tolerance for cymoxanil on
caneberry.

Regulator:	EPA 

Chemical:	Cymoxanil

Crop:	Caneberry

PHI:	0

App. Rate:

	Submitter:



Residues

	2.000

	2.150

	0.360

	0.340

	1.400

	1.700

	0.950

	0.980

	0.530

	0.540

	0.520

	0.340



Figure I- 3.  Lognormal probability plot of cymoxanil field trial data
for caneberry.

Figure I- 4.   Tolerance spreadsheet summary of cymoxanil field trial
data for caneberry.

 PAGE   

Page   PAGE  1  of   NUMPAGES  27 

Cymoxanil	Summary of Analytical Chemistry and Residue Data	DP Num: 
324447

Page   PAGE  27  of   NUMPAGES  27 

