Diquat Dibromide Summary of Analyt ical Chemistry and Residue Data DP#: 375811

Page 1 of 11 UNITED STA

TES ENVIRONMENTA L PROTECTION A GENCY WASHINGTON, D.C. 20460OFFICE OF CHEMICAL SAFETY AND POLLUTION PREVENTION

MEMORANDUM May 12, 2010 SUBJECT: Diquat Dibromide Petition for the Establishment of Permanent T olerances for

New Use on Canola. Summary of Analy tical Chemistry

and Residue Data. PC Code: 032201 DP Barcode s : D 375811 Decision No s .: 423144 Re gistration No s . : 100
- 1061 Petition No s. : 9F7639 Regulatory Action: Section 3 Risk A ss essment Type : NA Case No.: 0288 T XR No. : NA CAS No.: 85
- 00
- 7 MRID No . : See MRI D Summary Table 40 CFR: 180. 226 FROM: Becky

Daiss , Biologist Risk Assessment Branch 4 Health Effects Division (7509P) THROUGH: Susan Hummel , Senior Scientist

Risk Assessment Branch 4 Health Effects Division (7509P) TO: Bethany

Benbow , Risk Manager Reviewer Herbicide Branch Registration Division (7508P)

MRID Sum ma ry Table MRID N o. Study Type Com me nts 47 910101 860.1 5 00 Canola Summarized in n ew DER; 47910101 .der.doc 47910102 860.1 5 00 Canola Summarized in n ew DER; 4791010 1 .der.doc 47910103 860. 1340 Canola Summarized in n ew DER; 4791010 3 .der.docDiquat Dibromide Summary of Analyt ical Chemistry and Residue Data DP#: 375811

Page 2 of 11 Executive Summary Diquat dibromide (6,7

- dihydrodipy rido(1,2

- a:2', 1'

- c)py

razinediium dibromide) is a non

- selective contact herbicide, desiccant, and plant growth regulator primarily registered as a general herbicide for the control of broadleaf and grassy weeds on terrestrial non

- crop and aquatic areas. Diquat dibromide is also registered as a preharvest desiccant in potato and crops grown for seed including alfalfa, carrot, clover, radish, sorghum, soy bean, and turnip. Special local need registrations have recently been granted for the use of diquat dibromide as a postharvest desiccant on cantaloupe, cucumber, pepper, squash, tomato, and watermelon. The diquat dibromide formulations registered for use on aquatic areas and food/feed crops are the 0.2 and 2 lb cation/gal soluble concentrate/liquid (SC/L ). On crops, these formulations may be applied as preplant or preemergence broadcast applications or as preharvest/postharvest desiccants using ground or aerial equipment. On noncrop aquatic areas, the formulations registered may be applied as surface, sub

- surface, or bottom placement treatments [Source: REFS search, 8/7/01]

. The established tolerances for residues of diquat dibromide in/on raw agricultural commodities and in animal products are presently expressed in terms of the diquat cation [ Source: 40 CFR §180.226 (a) and (b)]

. Tolerance levels of 0.05

- 0.1 ppm are established for crop commodities and 0.02 ppm for animal commodities. Under PP#9 F7639, Sy

ngenta Crop Protection Inc is supporting the use of diquat dibromide as a harvest aid dessicant on canola. Sy ngenta has submitted the label Reglone Desiccant (EPA Reg. No. 100
- 1061 ) . Reglone Dessicant is a soluble concentrate containing 3.73 lbs diquat dibromide salt per gallon equivalent to 2 lbs diquat cation per gallon. An application rate of 0. 5 lb ai/A is proposed with a limit of one application per season. A 7 day pre harvest interval (PHI ) is required with harvest no later than 10 day s after application

. Ground or aerial application equipment is permitted. The r egistrant is also proposing an HPL C analy tical method as a new enforcement method for the determination of residues of diquat in crops, including oil seed crops ( A naly tical M ethod N umber RAM 272/02 , “The Determination of Residues of Paraquat and Diquat in crops and Soil

– A High Performance Liquid Chromatographic Method”). Regulatory Recommendations and Residue Chemistry Deficiencies HED has examined the residue chemistry database for diquat dibromide. There are no residue chemistry issues that would preclude establishing a tolerance and granting a conditional registration for the requested use of diquat dibromide or establishment of the following tolerances for residues of the diquat cation dibromide : Canola, seed

................................ ................................ ..................... 2 .0 ppm Cano la, meal

................................ ................................ .................... 6 .0 ppm The registration is conditional based on the submission the I R
- 4 data on preharvest dessicant use of diquat dibromide on canola. Sy ngenta Crop Protection, Inc. has submitted field trial data from studies conducted in W.Diquat Dibromide Summary of Analyt ical Chemistry and Residue Data DP#: 375811

Page 3 of 11 Germany and the UK to support use of diquat dibromide as a preharvest dessicant on canola. No field trial data from the United States or Canada are currently available. However I R
- 4 is currently conducting studies for preharvest dessicant use of diquat dibromide on ca nola. The HED ChemSAC determined that the EU data would support the establishment of a tolerance of 1 ppm on canola seed and the conditional registration of diquat dibromide on canola as a harvest aid/desiccant. The tolerance on canola seed has been in creased from 1 ppm to 2 ppm to harmonize with the Codex MRL , and a tolerance of 6 ppm is recommended for canola meal, based on a maximum theoretical concentration factor of 3X. HED is aware that IR
- 4 is currently conducting studies in the U.S. to support the preharvest desiccant use of diquat dibromide on canola. Residues of diquat dibromide on canola grown in the U.S. are not expected to differ significantly

from residues reported in the EU studies, since harvest aid/desiccant applications are made late in the growing season with little time between application and harvest. In addition, since the recommended tolerances for canola seed and meal have been increased by a factor of 2X to harmonize with Codex, there is little chance residues in the U.S. trial s will exceed these tolerances. Nevertheless, since the I R
- 4 field work has already been completed and the study reports will be available in July , 2011, HED recommends that these studies be required as a condition of registration to confirm the recommend ed tolerance levels. Sy ngenta provided insufficient information on storage durations/conditions of canola samples in the European crop field trials for use of diquat as a dessicant on canola. Data on l ength of storage of canola samples prior to analy sis from the W. German and UK trials is required. Although the length of storage prior to analy sis is unknown, based on the structure of diquat, residues in frozen storage are expected to be stable much longer than the 6 to 8 months for which storage stability data are available. Therefore, lack of data on length of storage is not expected to impact the risk assessment. Sy ngenta has proposed a new enforcement method

- Analy tical Method Number RAM 272/02 “The Determination of Residues of Paraquat and Diquat in crops and Soil

– A High Performance Li quid Chromatographic Method.” Samples are extracted by refluxing in dilute sulphuric acid. The filtered digest is diluted and percolated through a column of cation exchange resin which retains the diquat. The co lumn is washed with a hydrochloric acid, ammonium chloride and deionized water solution. Diquat residues are eluted with saturated ammonium chloride solution. Final determination of diquat residues is made with ion

- pair HPL C with UV detection. Reports o n the method validation (RJ201B) and the I LV (ZEN 0396) have been submitted to the Agency

. Based on HED’s analy sis, the proposed analy tical method is classified as scientifically acceptable

. HED recently

completed a risk assessment for a Section 18 Em ergency Exemption for use of diquat dibromide on c anola grown in Oklahoma and Kentucky (M. Doherty , D355407, 12/3/09)

. The use requested for this Section 3 registration is identical to that asses sed for the Section 18 request. Therefore a new risk assessm ent is not needed. Background Diquat dibromide is a non

- selective contact herbicide, algicide, dessicant, and defoliant. As a herbicide/algicide, it is used to control aquatic and terrestrial weeds. It is used as a preharvestDiquat Dibromide Summary of Analyt ical Chemistry and Residue Data DP#: 375811

Page 4 of 11 dessicant/defoliant to facilitate the harvest of potatoes and various crops grown for seed. Diquat dibromide works as a dessicant by reacting with molecular oxygen to produce a superoxide anion in treated plants. The oxidative activity , which occurs subsequent to formation of the oxygen radicals, rapidly destroy s plant cell membranes. The nomenclature and phy sicochemical properties of diquat dibromide are shown in Tables 1 and 2. Table 1. Diquat dibrom ide and Diquat dibrom ide PotassiumSalt Nom enclature Chemical Structu

re

Common name D iquat dibromide Company experimental name NA IUPAC name 9,10
- dihydro

- 8a,10a
- diazoniaphenanthrene dibromide CAS name 6,7
- dihydrodipyrido[1,2

- a:2 ′,1′

- c]pyrazinediium dibromide CAS # 85
- 00
- 7 End

- use product (EP) Reglone Dessicant herbicide (EPA Reg No. 1 00
- 1061 Table 2. Physicochem ical Properties of Diquat Dibrom ide Param eter Value Reference Mol Wt 344.1 (Cation

– 184) The Pesticide Manual 11 th Edition Melting point/range 300 °C D277710 pH Not Provided NA Density (20°C) 1.22
- 1.27 The Pesticide Manu al 11 th Edition Water solubility (20°C) 70 0 g/L D277710
. Solvent solubility slightly soluble in alcohol and hydroxylic solvents, and practically insoluble in nonpolar organic solvents D277710

Vapour pressure at 20°C Negligible < 10
- 5 mbar The agroc hemicals handbook 1983 Dissociation constant (pK a ) Not Provided NA K OW Octanol/water partition coefficient as Log P OW at 20°C - 4.60 The Pesticide Manual 11 th Edition UV/visible absorption spectrum Neutral and acidic conditions

- one major peak at 309. 5 nanometers. Basic conditions

- two major peaks at 309.0 and 217.0 nanometers. D349998

860.1200 Directions for Use The petitioner submitted a draft label for label Reglone Desiccant (EPA Reg. No. 100

- 1061 )

. An application rate of 0. 5 lb ai/A is proposed with a limit of one application per season. A 7 day pre harvest interval (PHI ) is required with harvest no later than 10 day s after application

. Ground or aerial application equipment is permitted.Diquat Dibromide Summary of Analyt ical Chemistry and Residue Data DP#: 375811

Page 5 of 11 Table 3 . Sum ma ry of Directions for Use of Diquat Dibrom ide on Canola Applic. Timing, Type, and Equip. Form ulation

[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
Harvest Aid Broadcast Aerial or Ground 2 lb (diquat

cation)/gal SC [100

- 1061] 0.5 1 0.5 7 Harvest no later than 10 days after application Conclusions . The label is adequate to allow evaluation of the residue data relative to the proposed use. 860.1300 Nature of the Residue - Plants MARC Decision, D P# 277765 , 11/8/2001 , T. Morton The reregistration requirements for plant metabolism are fulfilled. The qualitative nature of the residue in plants is adequately understood based on an acceptable potato metabolism study and a rat bioavailability

study

. The HED Metabolism Assessment Review Committee (MARC) has concluded the residue of concern for plants is the diquat cation (T. Morton, 11/8/01, D277765). The established tolerance expression for residues of diquat dibromide in/on plant commodities is ap propriate and no changes are required. The potato metabolism study indicated that no metabolism of diquat occurred in potato tubers following preharvest application of [ 14 C]diquat as a desiccant to potato stalks and stems. Soy bean and wheat metabolism st udies had also been previously submitted but were deemed marginal because of inadequate characterization and identification of 14 C

- residues in the commodities of concern. Attempts to further characterize 14 C

- residues from these studies were unsuccessful. Inlieu of the requirements for additional crop metabolism studies, the Agency recommended several options to satisfy reregistration requirements for this topic. The registrant opted to conduct a bioavailability study . The results of the bioavailability study showed that diquat plant residues are largely not bioavailable; < 5% of the 14 C is absorbed as a result of feeding diquat field residues in/on wheat chaff to rats. The retention of diquat residues in tissues was negligible (  0.004 ppm diquat equival ents) following dosing at  25x the maximum human dietary intake. 860.1300 Nature of the Residue - Livestock Canola meal is a livestock feedstuff. The qualitative nature of the residue in plants is adequately understood and the terminal residue of conce rn in plants is the diquat cation. 860.1340 Residue Analytical Methods DER 47910103 Enforcement Methods : The Pesticide Analy tical Manual (PAM) Vol. I I. lists a spectrophotometric method, designated as Method A (also referenced as Chevron Chemical Company RM
- 8
- 7) as available for the enforcement of tolerances for residues of diquat per seDiquat Dibromide Summary of Analyt ical Chemistry and Residue Data DP#: 375811

Page 6 of 11 in/on plant and in animal commodities. In this method, residues are extracted with sulfuric acid to free diquat from the bound state, absorbed on cation exchange res in, and eluted with saturated ammonium chloride. The diquat in the eluate is reduced by sodium dithionate, forming an intense green color and is measured spectrophotometrically at 337 μm. The limit of detection is 0.01 ppm. The registrant is proposing analy tical method number RAM 272/02 (“The Determination of Residues of Paraquat and Diquat in crops and Soil

– A High Performance Liquid Chromatographic Method ”) as an enforcement method for the determination of residues of diquat in crops, including oil se ed crops. RAM 272/02 has a limit of detection (L OD) in the range o f 0.01
- 0.05 mg/kg depending on the crop ty pe and mass of sample analy zed. With this method, samples are extracted by

refluxing in dilute sulphuric acid. The filtered digest is diluted and percolated through a column of cation exchange resin which retains the diquat and some of the natural crop constituents. The column is washed with hydrochloric acid, ammonium chloride solution to remove endogenous materials. Diquat residues are eluted w ith saturated ammonium chloride solution. A portion of the column eluent is passed through a preconditioned C18 solid phase extraction cartridge to remove further co

- extractives. Final determination of diquat residues is made using ion

- pair high performance liquid chromatography . S amples are analy zed against an appropriate concentration of diquat standard dissolved in saturated ammonium chloride solution. Based on HED’s analy sis, the proposed analy tical method is classified as scientifically

acceptable

. Data Collection Methods: Plant Protection Residue Analy tical Method No.5 was used for the measurement of diquat ion residues in canola seed. The samples were heated under reflux in 0.5 mol dm - 3 sulfuric acid solution. The filtered digest was percolat ed through a column of cation exchange resin which retained the diquat and some of the natural crop constituents. The column was sequentially

washed with dilute hydrochloric acid solution, 2.5% ammonium chloride solution and water. The diquat was then el uted with saturated ammonium chloride solution. A portion of the column eluent was treated with sodium dithionite in alkali. This reduced the diquat to a free radical, the light absorption of which was measured using a spectrophotometer. The estimated L OD of the method was reported as 0.005 ppm in the UK study and 0.05 for the West German study

. Plant Protection Residue Analy tical Method No 7A was used for the measurement of diquat ion in canola oil samples for the West German trials. The oil samples were thoroughly mixed by rolling with cation exchange resin for 2 hours. The resin was then placed in a column and was subjected to the same procedure as the seed samples. The L OD of the method was estimated to be 0.05 ppm. Conclusions : The data col lection method used in the submitted field trials is similar to the existing enforcement method. A dequate method validation and concurrent recovery data were attained in the field trial and processing studies . Therefore, H ED concludes that existing and p roposed enforcement methods are adequate for enforcement of the existing tolerances.Diquat Dibromide Summary of Analyt ical Chemistry and Residue Data DP#: 375811

Page 7 of 11 860.1360 Multiresidue Methods The FDA's PESTDATA dated 11/6/90 (Pam Vol. I , Appendix) indicates that recovery of diquat dibromide using Multiresidue Protocols is un likely . The updated PESTDATA dated 08/93 does not have an entry

for diquat dibromide. 860.1380 Storage Stability The requirements for storage stability data are fulfilled for purposes of reregistration. Adequate storage stability

data on diquat dibromi de are available to support the storage conditions and intervals of samples from magnitude of the residue studies in plants and animals. Residues of diquat per se are stable under frozen (

- 20  C) storage conditions for: (I ) up to six months in/on bell pep per, carrot roots, clover (hay and seed), lettuce, potato, rice (grain and straw), sorghum grain, soy bean, tomato and tomato processed fractions, and wheat (grain and straw); (ii) up to 8 months in processed fractions of sorghum grain and soy bean; and (iii ) up to 2 months in water and seafood samples. Sy ngenta provided very limited information on storage durations/conditions of canola samples in the crop field trials for use of diquat as a dessicant on canola. For the West German trials, representative s amples of seed were received deep frozen at Jealott’s Hill during September and October 1987; all samples were stored at

- 20 +/

- 5 oC prior to analy sis. For the UK trials, samples were stored at

- 20oC prior to analy sis. Data on length of storage prior to analy sis was not provided. Although the length of storage prior to an a ly s is is unknown, based on the structure of diquat , residues in frozen storage are expected to be stable much longer than the 6 to 8 months for which storage stability data are availabl e . Therefore, lack of data on length of storage is not expected to impact the risk assessment. However, data on length of storage of canola samples prior to analy sis should be submitted. 860.1400 Water, Fish, and Irrigated Crops There proposed label ch anges do not impact water, fish or irrigated crops. Therefore, data requirements for this guideline topic are not relevant to the request for use on canola

. 860.1460 Food Handling The requested label changes are not relevant to this guideline topic

. 860.1480 Meat, Milk, Poultry, and Eggs Canola meal is a livestock feedstuff . Recalculated dietary

burden s are provided in Table 4. Current tolerances are adequate. Residues will not exceed those used in the dietary exposure analy sis conducted for the S ection 18 Emergency Exemption. Table 4. Recalculated Dietary Burden Feed Com mo dity % Dry Matter a % Diet a Est Residues (ppm) Dietary Contribution ( ppm) b Beef Cattle Canola Meal 88 5 6.0 0.34 Soybean hulls 90 15 0.6 d 0.10Diquat Dibromide Summary of Analyt ical Chemistry and Residue Data DP#: 375811

Page 8 of 11 Potato proces sed w aste 15 80 0.5 f 2.66 TOTAL BURDEN 3.11 Dairy Cattle Canola Meal 88 10 6.0 0.68 Soybean hulls 90 20 0.6 d 0.13 Potato processed w aste 15 40 0.5 f 1.33 Sorghum grain 86 30 2.0 e 0.70 TOTAL BURDEN 2.84 Poultry Soybe an Seed NA 10 0.2 c 0.04 Canola Meal NA 15 6.0 d 0.09 Sorghum grain NA 75 2.0 e 1.50 TOTAL BURDEN 2.44 Swine Canola Meal NA 15 6.0 0.09 Sorghum grain NA 85 2.0 e 1.78 TOTAL BURDEN 2.60 a Table 1 (OPPTS Guideline 860.1000, Augu st 1996). b Contribution = [tolerance / % DM (if cattle)] X % diet). c To lerance level for soybean seed. d T olerance level for soybean hulls. e T olerance level for sorghum grain. f T olerance level for potato processed waste (wet peel residue levels used)

. Ina cattle feeding study , residues of diquat were non

- detectable (<0.003 ppm) in milk and tissues following feeding of diquat

- treated ryegrass silage to cattle at 3.6 ppm (1.2x and 1.3x the maximum dietary

intake for dairy

and beef cattle, respectivel y) for 30 day s. In another study , residues of diquat were nondetectable (<0.01 ppm) in milk following feeding of diquat

- treated clover hay

to cattle at 11 ppm (3.9x) for 34 day s. The established 0.02 ppm tolerance level for diquat residues in milk is ade quate. The established tolerances of 0.02 ppm for diquat residues in the fat, meat, and meat by products of cattle, goats, hogs, horses, and sheep may be raised to 0.05 ppm to achieve compatibility with the Codex maximum residue limit (MRL ). The maximum d ietary

burden for poultry

is 2.44 ppm; the calculation of the poultry burden is presented above. In a poultry feeding study , residues of diquat were mostly non - detectable (<0.005 ppm) in samples of eggs, fat, muscle, liver, and skin of chickens fed diquat at 1, 4.3, and 8.2 ppm diquat cation (0.4x, 1.8x, and 3.4x, respectively , the estimated dietary burden) in the diet for 28 day s. A single skin sample from the day

- 21, 8.2 ppm treatment group bore residues of 0.006 ppm. Residues in gizzard ranged from no n - detectable to 0.022 ppm. The established 0.02

- ppm tolerance level for diquat residues in poultry fat, meat, meat by

products and eggs may

be raised to 0.05 ppm to achieve compatibility with the Codex maximum residue limit (MRL ). 860.1500 Crop Field Tria ls DER References: 47910101 .der.doc Sy ngenta Crop Protection, Inc. has submitted field trial data for use of diquat dibromide as a preharvest dessicant on canola preharvest dessicant on canola. Field trials were conducted in West Germany and the United Kingdom. No field trial data from the United States or Canada are currently

available. However I R
- 4 is currently conducting studies for preharvest dessicant use of diquat dibromide on canola. Data from the IR
- 4 studies is expected to be available by Jul yDiquat Dibromide Summary of Analyt ical Chemistry and Residue Data DP#: 375811

Page 9 of 11 2011. The results of the field trials conducted in Europe are summarized in Table 5
. TABLE 5 . Sum ma ry of Residue Data fromCrop Field Trials with Diquat Com modity Total Applic.

Rate (lb a.i./A) (kg a.i./ha) PHI

(days) Residue Levels (ppm) n Mi n. Max. HAFT * Median (STMdR) Mean

(STMR) Std. Dev. Canola Seed 0.54/0.6 5
- 8 10 <0.05 0.48 0.48 0.155 0.232 0.13 Canola Seed 0.54/0.6 10
- 13 2 0.03 0.21 0.38 0.12 0.12 0.13 Canola Seed 0.54/0.6 20 2 0.18 0.38 0.38 0.28 0.28 0.14 Canola Oil 0.54/0.6 5
- 8 8 <0.05 <0.05 <0.05 <0.05 <0.05 0 Conclusion. Based on ChemSAC’s recommendation that the diquat team consider requiring data from trials conducted in the U.S. to supplement the available European field trial data, submission of the I R
- 4 data should be required as a condition of the canola registration. 860.1520 Processed Food and Feed A maximum theoretical concentration factor of 3X has been applied for the processed fraction canola meal. Residue data from field trials conducted in Germany demonstrat ed that diquat residues were not found in any of the oil samples. 860.1650 Submittal of Analytical Reference Standards An analy tical reference standard for diquat dibromide monohydrate is available in the Pesticide Standards Repos itory ( Personal Communication, Theresa Cole 3/25/10). 860.1850 & 1900 Confined and Field Accumulation in Rotational Crops There are no rotational crops associated with the proposed label changes. Therefore, data requirements pertaining to c onfined and f ield a ccumulation in r otational c rops are not relevant to th is tolerance petition. 860.1550 Proposed Tolerances The residues of concern in plant and animal commodities is the diquat cation. The tolerances proposed by

Sy ngenta and those recommended by HED are listed in Table 5. Codex has an estab lished maximum residue limit (M RL ) at 2 ppm Canada has an est ablished tolerance of 1 ppm. The residue definitions are identical. Therefore to harmonize with Codex HED recommends a tolerance of 2 ppm. Toleran ces are established in 40CFR 180.226 for residues of the plant growth regulator and herbicide diquat, (6,7

- dihydrodipy rido (1,2

- a:2'1'

- c)py

razinediium) derived from application of the dibromide salt and calculated as the cation

. The current tolerance expr ession is adequate.Diquat Dibromide Summary of Analyt ical Chemistry and Residue Data DP#: 375811

Page 10 of 11 Table 5. Tolerance Sum ma ry for Diquat Dibrom ide Commodity Established/ Proposed Tolerance (ppm) Recommended

Tolerance (ppm) Comments;

Correct Commodity Definition Proposed tolerances under §180. 226 Canola, seed 1 .0 2 .0 Canola, me al 3.0 6 .0 References DP#: 277710 Subject: Tolerance Reassessment of Diquat dibromide : Product and Residue Chemistry

Considerations

. From: T. Morton To: R. Daiss Dated: 1 2/ 13/2001 MRI D: NA Template Version September 2005Diquat Dibromide Summary of Analyt ical Chemistry and Residue Data DP#: 375811

Page 11 of 11 IN TERNATI ONAL RESI DUE LIMI T STATUS Chemical Name: 6,7

- dihydrodipyrido[1,2

- a :2 ′,1′

- c ]pyrazinediium dibromide Common Name: Diquat  Proposed tolerance

 Reevaluated tolerance  Other Date: 4/1/10

Codex Status (Maximum Residue L imits) U. S. Tolerances  No Codex proposal step 6 or above  No Codex proposal step 6 or above for th e crops requested Petition Number 9F639 DP Barcode: 375811 Other Identifier: Residue definition (step 8/CXL): Diquat cation. Generally available as dibromide. Reviewer/Branch: R. Daiss, RAB4 Residue definition: Diquat cation Crop (s) MRL (mg/kg) Cr op(s) Tolerance (ppm) Rape seed 2 Canola

Li mits for Canada Li mits for Mexico  No Limits  No Limits for the crops requested  No Limits  No Limits for the crops requested Residue definition: 9,10
- dihydro

- 8a,10a
diazoniaphenanthrene ion Residue definition: Mexico uses US tolerances and/or Codex MRLs for its export purposes. Crop(s) MRL(mg/kg) Crop(s) MRL(mg/kg) Rapeseed 1.0 Notes/Special Instructions: S. Funk, 04/01/2010